Patent Publication Number: US-10766919-B2

Title: Cyclic di-nucleotide compounds as sting agonists

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 62/204,677, filed Aug. 13, 2015, U.S. Provisional Patent Application No. 62/268,723, filed Dec. 17, 2015, and U.S. Provisional Patent Application No. 62/356,125, filed Jun. 29, 2016. 
    
    
     FIELD OF THE INVENTION 
     The present disclosure relates to cyclic di-nucleotide compounds and derivatives thereof that may be useful as STING (Stimulator of Interferon Genes) agonists that activate the STING pathway. The present disclosure also relates to processes for the synthesis and to uses of such cyclic di-nucleotide compounds. 
     BACKGROUND OF THE INVENTION 
     The immune system has evolved to recognize and neutralize different types of threats in order to maintain the homeostasis of the host, and it is generally broken down into two arms: adaptive and innate. The adaptive immune system is specialized to recognize antigens not naturally expressed in the host as foreign and to mount an anti-antigen response through the coordinated actions of many leukocyte subsets. The hallmark of adaptive immune responses is their ability to provide “memory” or long-lasting immunity against the encountered antigen. While this specific and long-lasting effect is critical to host health and survival, the adaptive immune response requires time to generate a full-blown response. 
     The innate immune system compensates for this time delay and is specialized to act quickly against different insults or danger signals. It provides the first line of defense against bacteria, viruses, parasites and other infectious threats, but it also responds strongly to certain danger signals associated with cellular or tissue damage. The innate immune system has no antigen specificity but does respond to a variety of effector mechanisms. Opsonization, phagocytosis, activation of the complement system, and production of soluble bioactive molecules such as cytokines or chemokines are all mechanisms by which the innate immune system mediates its response. By responding to these damage-associated molecular patterns (DAMPs) or pathogen-associated molecular patterns (PAMPs) described above, the innate immune system is able to provide broad protection against a wide range of threats to the host. 
     Free cytosolic DNA and RNA are among these PAMPs and DAMPs. It has recently been demonstrated that the main sensor for cytosolic DNA is cGAS (cyclic GMP-AMP synthase). Upon recognition of cytosolic DNA, cGAS catalyzes the generation of the cyclic-dinucleotide 2′-3′ cGAMP, an atypical second messenger that strongly binds to the ER-transmembrane adaptor protein STING. A conformational change is undergone by cGAMP-bound STING, which translocates to a perinuclear compartment and induces the activation of critical transcription factors IRF-3 and NF-κB. This leads to a strong induction of type I interferons and production of pro-inflammatory cytokines such as IL-6, TNF-α and IFN-γ. 
     The importance of type I interferons and pro-inflammatory cytokines on various cells of the immune system has been very well established. In particular, these molecules strongly potentiate T cell activation by enhancing the ability of dendritic cells and macrophages to uptake, process, present and cross-present antigens to T cells. The T cell stimulatory capacity of these antigen-presenting cells is augmented by the up-regulation of critical co-stimulatory molecules, such as CD80 or CD86. Finally, type I interferons can rapidly engage their cognate receptors and trigger the activation of interferon-responsive genes that can significantly contribute to adaptive immune cell activation. 
     From a therapeutic perspective, type I interferons are shown to have antiviral activities by directly inhibiting human hepatitis B virus and hepatitis C virus replication, and by stimulating immune responses to virally infected cells. Compounds that can induce type I interferon production are used in vaccines, where they act as adjuvants, enhancing specific immune responses to antigens and minimizing side effects by reducing dosage and broadening the immune response. 
     In addition, interferons, and compounds that can induce interferon production, have potential use in the treatment of human cancers. Such molecules are potentially useful as anti-cancer agents with multiple pathways of activity. Interferons can inhibit human tumor cell proliferation directly and may be synergistic with various approved chemotherapeutic agents. Type I interferons can significantly enhance anti-tumor immune responses by inducing activation of both the adaptive and innate immune cells. Finally, tumor invasiveness may be inhibited by interferons by modulating enzyme expression related to tissue remodeling. 
     In view of the potential of type I interferons and type I interferon-inducing compounds as anti-viral and anti-cancer agents, there remains a need for new agents that can induce potent type I interferon production. With the growing body of data demonstrating that the cGAS-STING cytosolic DNA sensory pathway has a significant capacity to induce type I interferons, the development of STING activating agents is rapidly taking an important place in today&#39;s anti-tumor therapy landscape. 
     SUMMARY OF THE INVENTION 
     The present disclosure relates to novel cyclic di-nucleotide compounds of general formula (I), general formula (I′), and/or general formula (I″). In particular, the present disclosure relates to compounds having the general structural formula (I): 
                         
or pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof, as described herein. The present disclosure also relates to compounds having general structural formula (I′):
 
                         
or pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof, as described herein. The present disclosure also relates to compounds having general structural formula (I″):
 
                         
or pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof, as described herein.
 
     Embodiments of the disclosure include compounds of general formula (I), compounds of general formula (I′), and/or compounds of general formula (I″), and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof, as well as synthesis and isolation of compounds of general formula (I), compounds of general formula (I′), and/or compounds of general formula (I″), and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof. Uses of compounds of general formula (I), compounds of general formula (I′), and/or compounds of general formula (I″) are also disclosed. 
     Other embodiments, aspects and features of the present disclosure are either further described in or will be apparent from the ensuing description, examples and appended claims. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Not Applicable 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present disclosure includes compounds of general formula (I), compounds of general formula (I′), and/or compounds of general formula (I″) above, and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof. These compounds and their pharmaceutically acceptable salts, hydrates, solvates, and/or prodrugs are useful as agents to induce interferon production. 
     A first embodiment of the disclosure relates to cyclic di-nucleotide compounds of general formula (I): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                             
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; Y and Y a  are each independently selected from the group consisting of —O—, —S—, —SO 2 —, —CH 2 —, and —CF 2 —; X a  and X a1  are each independently selected from the group consisting of O, C, and S; X b  and X b1  are each independently selected from the group consisting of O, C, and S; X c  and X c1  are each independently selected from the group consisting of O − , S − , OR 9 , and NR 9 R 9 ; X d  and X d1  are each independently selected from the group consisting of O and S; R 1  and R 1a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 1  and R 1a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 2  and R 2a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 3  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 4  and R 4a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 4  and R 4a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 5  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 6  and R 6a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 6  and R 6a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 7  and R 7a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 7  and R 7a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 8  and R 8a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 8  and R 8a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; each R 9  is independently selected from the group consisting of H, C 1 -C 20  alkyl,
 
                         
where each R 9  C 1 -C 20  alkyl is optionally substituted by 0 to 3 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; optionally R 1a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 1a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position; optionally R 2a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 2a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position; optionally R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position; optionally R 4  and R 5  are connected to form are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position; optionally R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position; optionally R 7  and R 8  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene; and optionally R 7a  and R 8a  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene.
 
     In specific aspects of this embodiment, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH or SH, X d  and X d1  are each O, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of 
                         
R 5  and R 3  are not both selected from the group consisting of H, F and OH. That is, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH or SH, X d  and X d1  are each O, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of
 
                         
either only one of R 5  and R 3  is selected from the group consisting of H, F, and OH, or neither R 5  and R 3  is selected from the group consisting of H, F, and OH. In further specific instances of this aspect, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH, X d  and X d1  are each O or S, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of
 
                         
R 5  and R 3  are not both selected from the group consisting of H, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, where said C 1 -C 6  alkyl, C 2 -C 6  alkenyl and C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I and OH.
 
     In further specific aspects of this embodiment, when Base 1  and Base 2  are each selected from the group consisting of 
                         
and R 2a  is F and R 5  is F, at least one of X c  and X c1  is SR 9 .
 
     In a first aspect of the first embodiment, Base 1  and Base 2  are each independently selected from the group consisting of 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 . In particular instances, Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 . In even more particular instances, Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 . In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above.
 
     In a second aspect of the first embodiment, Y and Y a  are each independently selected from the group consisting of —O— and —S—. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first aspect described above. 
     In a third aspect of the first embodiment, X a  and X a1  are each independently selected from the group consisting of O and S. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through second aspects described above. 
     In a fourth aspect of the first embodiment, X b  and X b1  are each independently selected from the group consisting of O and S. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through third aspects described above. 
     In a fifth aspect of the first embodiment, X c  and X c1  are each independently selected from the group consisting of O − , S − , OR 9 , and NR 9 R 9 , where each R 9  is independently selected from the group consisting of H, C 1 -C 20  alkyl, 
                         
where each R 9  C 1 -C 20  alkyl is optionally substituted by 0 to 3 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl. In particular instances, X c  and X c  are each independently selected from the group consisting of O − , S − ,
 
                         
In all instances of this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourth aspects described above.
 
     In a sixth aspect of the first embodiment, X d  and X d1  are each independently selected from the group consisting of O and S. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fifth aspects described above. 
     In a seventh aspect of the first embodiment, R 1  and R 1a  are each H. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through sixth aspects described above. 
     In an eighth aspect of the first embodiment, R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 2  and R 2a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 . In particular instances, R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through seventh aspects described above. 
     In a ninth aspect of the first embodiment, R 3  is selected from the group consisting H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 . In particular instances, R 3  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through eighth aspects described above. 
     In a tenth aspect of the first embodiment, R 4  and R 4a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 4  and R 4a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 . In particular instances, R 4  and R 4a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through ninth aspects described above. 
     In an eleventh aspect of the first embodiment, R 5  is selected from the group consisting of H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 . In particular instances, R 5  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through tenth aspects described above. 
     In a twelfth aspect of the first embodiment, R 6  and R 6a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, and C 2 -C 6  alkynyl. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through eleventh aspects described above. 
     In a thirteenth aspect of the first embodiment, R 7  and R 7a  are each H. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through twelfth aspects described above. 
     In a fourteenth aspect of the first embodiment, R 8  and R 8a  are each H. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through thirteenth aspects described above. 
     In a fifteenth aspect of the first embodiment, R 1a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 1a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourteenth aspects described above. 
     In a sixteenth aspect of the first embodiment, R 2a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 2a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourteenth aspects described above. 
     In a seventeenth aspect of the first embodiment, R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, and —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourteenth aspects described above. 
     In an eighteenth aspect of the first embodiment, R 4  and R 5  are connected by C 1 -C 6  alkylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourteenth aspects described above. 
     In a nineteenth aspect of the first embodiment, R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourteenth aspects described above. 
     In a twentieth aspect of the first embodiment, R 7  and R 8  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourteenth aspects described above. 
     In a twenty-first aspect of the first embodiment, R 7a  and R 8a  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above or in the first through fourteenth aspects described above. 
     In a twenty-second aspect of the first embodiment, Base 1  and Base 2  are each independently selected from the group consisting of 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; Y and Y a  are each independently selected from the group consisting of —O—, —S—, —SO 2 —, —CH 2 —, and —CF 2 —; X a  and X a1  are each independently selected from the group consisting of O and S; X b  and X b1  are each independently selected from the group consisting of O and S; X c  and X c1  are each independently selected from the group consisting of O − , S − , OR 9 , and NR 9 R 9 ; X d  and X d1  are each independently selected from the group consisting of O and S; R 1  and R 1a  are each H; R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 2  and R 2a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 3  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 4  and R 4a  are each independently selected from the group consisting of H, C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 4  and R 4a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 5  is selected from the group consisting of H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 6  and R 6a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, and C 1 -C 6  haloalkyl, where said R 6  and R 6a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 7  and R 7a  are each H; R 8  and R 8a  are each H; each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; optionally R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, and —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position or optionally R 4  and R 5  are connected by C 1 -C 6  alkylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above.
 
     In a twenty-third aspect of the first embodiment, the compound of formula (I) is a compound of formula (Ia): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                                               
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; X c  and X c1  are each independently selected from the group consisting of O − , S − , OR 9 , and NR 9 R 9 ; R 3  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 5  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 3  and R 5  are not both selected from the group consisting of OH, C 1 -C 6  alkyl substituted with OH, and C 1 -C 6  haloalkyl substituted with OH; and each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above.
 
     In a twenty-fourth aspect of the first embodiment, the compound of formula (I) is a compound of formula (Ib): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                                               
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; X c  and X c1  are each independently selected from the group consisting of O − , S − , OR 9 , and NR 9 R 9 ; R 1a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 1a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 2a  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 2a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 3  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 5  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 3  and R 5  are not both selected from the group consisting of OH, C 1 -C 6  alkyl substituted with OH, and C 1 -C 6  haloalkyl substituted with OH; R 6a  is selected from the group consisting of H, F, Cl, I, Br, OH, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, and C 2 -C 6  alkynyl; each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; and optionally R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, and —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above.
 
     In a twenty-fifth aspect of the first embodiment, the compound of formula (I) is a compound of formula (Ic): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                                               
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; X c  and X c1  are each independently selected from the group consisting of O − , S − , OR 9 , and NR 9 R 9 ; R 3  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 4  is selected from the group consisting of H, F, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 4  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 5  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; R 3  and R 5  are not both selected from the group consisting of OH, C 1 -C 6  alkyl substituted with OH, and C 1 -C 6  haloalkyl substituted with OH; R 6a  is selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 6a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, I, Br, and OH; each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; and optionally R 4  and R 5  are connected by C 1 -C 6  alkylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In this aspect, all other groups are as provided in the general formula (I) of the first embodiment above.
 
     A twenty-sixth aspect of the first embodiment relates to a pharmaceutical composition, said pharmaceutical composition comprising (a) a compound according to any one of general formula (I) of the first embodiment above or in the first through twenty-fifth aspects described above or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and (b) a pharmaceutically acceptable carrier. 
     A twenty-seventh aspect of the first embodiment relates to methods of inducing an immune response in a subject, comprising administering a therapeutically effective amount of a compound according to any one of general formula (I) of the first embodiment above or in the first through twenty-fifth aspects described above or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof to the subject. 
     A twenty-eighth aspect of the first embodiment relates to methods of inducing an immune response in a subject, comprising administering a therapeutically effective amount of a composition according to the twenty-sixth aspect described above to the subject. 
     A twenty-ninth aspect of the first embodiment relates to methods of inducing a STING-dependent type I interferon production in a subject, comprising administering a therapeutically effective amount of a compound according to any one of general formula (I) of the first embodiment above or in the first through twenty-fifth aspects described above or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof to the subject. 
     A thirtieth aspect of the first embodiment relates to methods of inducing a STING-dependent type I interferon production in a subject, comprising administering a therapeutically effective amount of a composition according to the twenty-sixth aspect described above to the subject. 
     A thirty-first aspect of the first embodiment relates to methods of inducing a STING-dependent cytokine production in a subject, comprising administering a therapeutically effective amount of a compound according to any one of general formula (I) of the first embodiment above or in the first through twenty-fifth aspects described above or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof to the subject. 
     A thirty-second aspect of the first embodiment relates to methods of inducing a STING-dependent cytokine production in a subject, comprising administering a therapeutically effective amount of a composition according to the twenty-sixth aspect described above to the subject. 
     A second embodiment of the disclosure relates to cyclic di-nucleotide compounds of general formula (I′): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                                                                                   
where Base and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3 -6 cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; Y and Y a  are each independently selected from the group consisting of —O— and —S—; X a  and X a1  are each independently selected from the group consisting of O, and S; X b  and X b1  are each independently selected from the group consisting of O, and S; X c  and X c1  are each independently selected from the group consisting of OR 9 , SR 9 , and NR 9 R 9 ; X d  and X c1  are each independently selected from the group consisting of O and S; R 1  and R 1a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 1  and R 1a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 2  and R 2a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 3  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 4  and R 4a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 4  and R 4a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 5  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, NR 9 R 9 , and N 3 ; R 6  and R 6a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 6  and R 6a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 7  and R 7a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 7  and R 7a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 8  and R 8a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 8  and R 8a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; each R 9  is independently selected from the group consisting of H, C 1 -C 20  alkyl,
 
                         
where each R 9  C 1 -C 20  alkyl is optionally substituted by 0 to 3 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; optionally R 1a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 1a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position; optionally R 2a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 2a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position; optionally R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position; optionally R 4  and R 5  are connected to form are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position; optionally R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position; optionally R 7  and R 8  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene; and optionally R 7a  and R 8a  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene.
 
     In specific aspects of this embodiment, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH or SH, X d  and X d1  are each O, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of 
                         
R 5  and R 3  are not both selected from the group consisting of H, F and OH. That is, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH or SH, X d  and X d1  are each O, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of,
 
                         
either only one of R 5  and R 3  is selected from the group consisting of H, F, and OH, or neither R 5  and R 3  is selected from the group consisting of H, F, and OH. In further specific instances of this aspect, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH, X d  and X d1  are each O or S, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of
 
                         
R 5  and R 3  are not both selected from the group consisting of H, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, where said C 1 -C 6  alkyl, C 2 -C 6  alkenyl and C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I and OH.
 
     In further specific aspects of this embodiment, when Base 1  and Base 2  are each selected from the group consisting of 
                         
and R 2a  is F and R 5  is F, at least one of X c  and X c1  is SR 9 .
 
     In a first aspect of the second embodiment, Base 1  and Base 2  are each independently selected from the group consisting of 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 . In particular instances, Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 . In even more particular instances, Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 . In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above.
 
     In a second aspect of the second embodiment, X c  and X c1  are each independently selected from the group consisting of OR 9 , SR 9 , and NR 9 R 9 , where each R 9  is independently selected from the group consisting of H, C 1 -C 20  alkyl, 
                         
where each R 9  C 1 -C 20  alkyl is optionally substituted by 0 to 3 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl. In particular instances, X c  and X c1  are each independently selected from the group consisting of O − , S − ,
 
                         
In all instances of this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first aspect described above.
 
     In a third aspect of the second embodiment, R 1  and R 1a  are each H. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through second aspects described above. 
     In a fourth aspect of the second embodiment, R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 2  and R 2a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 . In particular instances, R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through third aspects described above. 
     In a fifth aspect of the second embodiment, R 3  is selected from the group consisting H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 . In particular instances, R 3  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In even more particular instances, R 3  is selected from NH 2  and N 3 . In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through fourth aspects described above. 
     In a sixth aspect of the second embodiment, R 4  and R 4a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 4  and R 4a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 . In particular instances, R 4  and R 4a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In even more particular instances, R 4  and R 4a  are each F. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through fifth aspects described above. 
     In a seventh aspect of the second embodiment, R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, NH 2 , N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, NR 9 R 9 , and N 3 . In particular instances, R 5  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, CN, N 3 , CF 3 , CH 3 , CH 2 OH, and CH 2 CH 3 . In even more particular instances, R 5  is selected from NH 2  and N 3 . In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through sixth aspects described above. 
     In an eighth aspect of the second embodiment, R 6  and R 6a  are each independently selected from the group consisting of H, F, Cl, I, Br, OH, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, and C 2 -C 6  alkynyl. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through seventh aspects described above. 
     In a ninth aspect of the second embodiment, R 7  and R 7a  are each independently selected from the group consisting of H and C 1 -C 6  alkyl. In particular instances, R 7  and R 7a  are each independently selected from the group consisting of H and CH 3 . In more particular instances, R 7a  is CH 3 . In additional instances, R 7  and R 7a  are each H. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through eighth aspects described above. 
     In a tenth aspect of the second embodiment, R 8  and R 8a  are each independently selected from the group consisting of H and C 1 -C 6  alkyl. In particular instances, R 8  and R 8a  are each independently selected from the group consisting of H and CH 3 . In more particular instances, R 8a  is CH 3 . In additional instances, R 8  and R 8a  are each H. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through ninth aspects described above. 
     In an eleventh aspect of the second embodiment, R 1a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 1a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through tenth aspects described above. 
     In a twelfth aspect of the second embodiment, R 2a  and R 3  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, C 2 -C 6  alkynylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 2a  and R 3  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through eleventh aspects described above. 
     In a thirteenth aspect of the second embodiment, R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, and —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through eleventh aspects described above. 
     In a fourteenth aspect of the second embodiment, R 4  and R 5  are connected by C 1 -C 6  alkylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through eleventh aspects described above. 
     In a fifteenth aspect of the second embodiment, R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 5  and R 6  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through eleventh aspects described above. 
     In a sixteenth aspect of the second embodiment, R 7  and R 8  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through eleventh aspects described above. 
     In a seventeenth aspect of the second embodiment, R 7a  and R 8a  are connected to form C 1 -C 6  alkylene, C 2 -C 6  alkenylene, or C 2 -C 6  alkynylene. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above or in the first through eleventh aspects described above. 
     In an eighteenth aspect of the second embodiment, Base 1  and Base 2  are each independently selected from the group consisting of 
                         
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; Y and Y a  are each independently selected from the group consisting of —O— and —S—; X a  and X a1  are each independently selected from the group consisting of O and S; X b  and X b1  are each independently selected from the group consisting of O and S; X c  and X c1  are each independently selected from the group consisting of OR 9 , SR 9 , and NR 9 R 9 ; X d  and X d1  are each independently selected from the group consisting of O and S; R 1  and R 1a  are each H; R 2  and R 2a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 2  and R 2a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 4  and R 4a  are each independently selected from the group consisting of H, C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 4  and R 4a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, NH 2 , N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, NR 9 R 9 , and N 3 ; R 6  and R 6a  are each independently selected from the group consisting of H, F, Cl, Br, I, OH, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, and C 1 -C 6  haloalkyl, where said R 6  and R 6a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 7  and R 7a  are each H; R 8  and R 8a  are each H; each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; optionally R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, and —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position or optionally R 4  and R 5  are connected by C 1 -C 6  alkylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In all instances of this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above.
 
     In a nineteenth aspect of the second embodiment, the compound of formula (I′) is a compound of formula (I′a): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                                                                                   
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; X c  and X c1  are each independently selected from the group consisting of OR 9 , SR 9 , and NR 9 R 9 ; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 3  and R 5  are not both selected from the group consisting of: OH, R 5  C 1 -C 6  alkyl substituted with OH, or C 1 -C 6  haloalkyl substituted with OH; and each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl. In all instances of this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above.
 
     In a twentieth aspect of the second embodiment, the compound of formula (I′) is a compound of formula (I′b): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                                                                                   
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; X c  and X c1  are each independently selected from the group consisting of OR 9 , SR 9 , and NR 9 R 9 ; R 1a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl, where said R 1a  C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, OH, CN, and N 3 ; R 2a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 2a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 3  and R 5  are not both selected from the group consisting of OH, C 1 -C 6  alkyl substituted with OH, and C 1 -C 6  haloalkyl substituted with OH; R 6a  is selected from the group consisting of H, F, Cl, Br, I, OH, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, and C 2 -C 6  alkynyl; each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; and optionally R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, and —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above.
 
     In a twenty-first aspect of the second embodiment, the compound of formula (I′) is a compound of formula (I′c): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                                                                                                                   
where Base 1  and Base 2  each may be independently substituted by 0-3 substituents R 10 , where each R 10  is independently selected from the group consisting of F, Cl, I, Br, OH, SH, NH 2 , C 1-3  alkyl, C 3-6  cycloalkyl, O(C 1-3  alkyl), O(C 3-6  cycloalkyl), S(C 1-3  alkyl), S(C 3-6  cycloalkyl), NH(C 1-3  alkyl), NH(C 3-6  cycloalkyl), N(C 1-3  alkyl) 2 , and N(C 3-6  cycloalkyl) 2 ; X c  and X c1  are each independently selected from the group consisting of OR 9 , SR 9 , and NR 9 R 9 ; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 3  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 4  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 4  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 5  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; R 6a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, and C 1 -C 6  haloalkyl, where said R 6a  C 1 -C 6  alkyl or C 1 -C 6  haloalkyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I, and OH; each R 9  is independently selected from the group consisting of H, C 2 -C 3  alkyl,
 
                         
where each R 9  C 2 -C 3  alkyl is optionally substituted by 1 to 2 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; and optionally R 4  and R 5  are connected by C 1 -C 6  alkylene, —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 4  and R 5  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 5  position. In this aspect, all other groups are as provided in the general formula (I′) of the second embodiment above.
 
     A twenty-second aspect of the second embodiment relates to a pharmaceutical composition, said pharmaceutically acceptable composition comprising (a) a compound according to any one of general formula (I′) of the second embodiment above or in the first through twenty-first aspects described above or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof, and (b) a pharmaceutically acceptable carrier. 
     A twenty-third aspect of the second embodiment relates to methods of inducing an immune response in a subject, comprising administering a therapeutically effective amount of a compound according to any one of general formula (I′) of the second embodiment above or in the first through twenty-first aspects described above or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof to the subject. 
     A twenty-fourth aspect of the second embodiment relates to methods of inducing an immune response in a subject, comprising administering a therapeutically effective amount of a composition according to the twenty-second aspect described above or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof to the subject. 
     A twenty-fifth aspect of the second embodiment relates to methods of inducing a STING-dependent type I interferon production in a subject, comprising administering a therapeutically effective amount of a compound according to any one of general (I′) of the second embodiment above or in the first through twenty-first aspects described above or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof to the subject. 
     A twenty-sixth aspect of the second embodiment relates to methods of inducing a STING-dependent type I interferon production in a subject, comprising administering a therapeutically effective amount of a composition according to the twenty-second aspect described above to the subject. 
     A twenty-seventh aspect of the second embodiment relates to methods of inducing a STING-dependent cytokine production in a subject, comprising administering a therapeutically effective amount of a compound according to any one of general (I′) of the second embodiment above or in the first through twenty-first aspects described above or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof to the subject. 
     A thirty-third aspect of the second embodiment relates to methods of inducing a STING-dependent cytokine production in a subject, comprising administering a therapeutically effective amount of a composition according to the twenty-second aspect described above to the subject. 
     A third embodiment of the disclosure relates to cyclic di-nucleotide compounds of general formula (I″): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
Y is selected from the group consisting of —O— and —S—; X c  and X c1  are each independently selected from the group consisting of OR 9  and SR 9 ; X d  and X d1  are each independently selected from the group consisting of O and S; R 2a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 4  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 6a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; each R 9  is independently selected from the group consisting of H, C 1 -C 20  alkyl,
 
                         
where each R 9  C 1 -C 20  alkyl is optionally substituted by 0 to 3 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl; and optionally R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position.
 
     In specific aspects of this embodiment, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH or SH, X d  and X d1  are each O, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of 
                         
R 5  and R 3  are not both selected from the group consisting of H, F and OH. That is, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH or SH, X d  and X d1  are each O, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of
 
                         
either only one of R 5  and R 3  is selected from the group consisting of H, F, and OH, or neither R 5  and R 3  is selected from the group consisting of H, F, and OH. In further specific instances of this aspect, when Y and Y a  are each O, X a  and X a1  are each O, X b  and X b1  are each O, and X c  and X c1  are each OH, X d  and X d1  are each O or S, R 1  and R 1a  are each H, R 2  is H, R 6  and R 6a  are each H, R 7  and R 7a  are each H, R 8  and R 8a  are each H, and Base 1  and Base 2  are each selected from the group consisting of
 
                         
R 5  and R 3  are not both selected from the group consisting of H, C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, where said C 1 -C 6  alkyl, C 2 -C 6  alkenyl and C 2 -C 6  alkynyl are substituted by 0 to 3 substituents selected from the group consisting of F, Cl, Br, I and OH.
 
     In further specific aspects of this embodiment, when Base 1  and Base 2  are each selected from the group consisting of 
                         
and R 2a  is F and R 5  is F, at least one of X c  and X c1  is SR 9 .
 
     In a first aspect of the third embodiment, the compound of formula (I″) is a compound of formula (I″a): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
Y is selected from the group consisting of —O— and —S—; X c  and X c1  are each independently selected from the group consisting of OR 9  and SR 9 ; X d  and X d1  are each independently selected from the group consisting of O and S; R 2a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 6a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; and each R 9  is independently selected from the group consisting of H, C 1 -C 20  alkyl,
 
                         
where each R 9  C 1 -C 20  alkyl is optionally substituted by 0 to 3 substituents independently selected from the group consisting of OH, —O—C 1 -C 20  alkyl, —S—C(O)C 1 -C 6  alkyl, and C(O)OC 1 -C 6  alkyl. In instances of this aspect, Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
Y is selected from the group consisting of —O— and —S—; X c  and X c1  are each independently selected from the group consisting of OR 9  and SR 9 ; X d  and X d1  are each independently selected from the group consisting of O and S; R 2a  is F; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 6a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; and each R 9  is independently H.
 
     In a second aspect of the third embodiment, the compound of formula (I″) is a compound wherein R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. 
     In a third aspect of the third embodiment, the compound of formula (I″) is a compound of formula (I″b): 
                         
or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, wherein Base 1  and Base 2  are each independently selected from the group consisting of
 
                         
Y is selected from the group consisting of —O— and —S—; X c  and X c1  are each independently selected from the group consisting of OR 9  and SR 9 ; X d  and X d1  are each independently selected from the group consisting of O and S; R 3  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 4  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 5  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, NH 2 , N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; R 6a  is selected from the group consisting of H, F, Cl, Br, I, OH, CN, N 3 , C 1 -C 6  alkyl, C 2 -C 6  alkenyl, C 2 -C 6  alkynyl, C 1 -C 6  haloalkyl, C 2 -C 6  haloalkenyl, C 2 -C 6  haloalkynyl, —O—C 1 -C 6  alkyl, —O—C 2 -C 6  alkenyl, and —O—C 2 -C 6  alkynyl; each R 9  is independently H; and R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, such that where R 3  and R 6a  are connected to form —O—C 1 -C 6  alkylene, —O—C 2 -C 6  alkenylene, or —O—C 2 -C 6  alkynylene, said O is bound at the R 3  position. In instances of this aspect, Base 1  and Base 2  are each independently selected from the group consisting of
 
     
       
         
         
             
             
         
       
     
     In a fourth aspect of the third embodiment, the compound of formula (I″) is a compound wherein at least one of Base 1  and Base 2  are each independently selected from the group consisting of 
     
       
         
         
             
             
         
       
     
     A fifth aspect of the third embodiment relates to a pharmaceutical composition, said pharmaceutical composition comprising (a) a compound according to any one of general formula (I″) of the third embodiment or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof; and (b) a pharmaceutically acceptable carrier. 
     A sixth aspect of the third embodiment relates to methods of inducing an immune response in a subject, comprising administering a therapeutically effective amount of a compound according to general formula (I″) of the third embodiment above or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof to the subject. 
     A seventh aspect of the third embodiment relates to methods of inducing an immune response in a subject, comprising administering a therapeutically effective amount of a composition according to the fifth aspect described above to the subject. 
     An eighth aspect of the third embodiment relates to methods of inducing a STING-dependent type I interferon production in a subject, comprising administering a therapeutically effective amount of a compound according general formula (I″) of the third embodiment above or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof to the subject. 
     A ninth aspect of the third embodiment relates to methods of inducing a STING-dependent type I interferon production in a subject, comprising administering a therapeutically effective amount of a composition according to the fifth aspect described above to the subject. 
     A tenth aspect of the third embodiment relates to methods of inducing a STING-dependent cytokine production in a subject, comprising administering a therapeutically effective amount of a compound according to general formula (I″) of the third embodiment above or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof to the subject. 
     An eleventh aspect of the third embodiment relates to methods of inducing a STING-dependent cytokine production in a subject, comprising administering a therapeutically effective amount of a composition according to the fifth aspect described above to the subject. 
     In an additional embodiment, the compound is selected from the group consisting of 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof. In aspects of this embodiment, the compound is selected from the group consisting of
 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof. In particular aspects, the compound is selected from the group consisting of
 
                                                                                                                                                                                                                                                                                                                                                                               
and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof. In more particular aspects of this embodiment, the compound is selected from the group consisting of
 
                                                                                                                                                                                                                                                                                                                                           
and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof. In still more particular aspects, the compound is selected from the group consisting of
 
                                                                                                 
and pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof.
 
     In another embodiment, for the compounds of general formula (I), compounds of general formula (I′) and compounds of general formula (I″), variables Base 1 , Base 2 , Y, Y a , X a , X a1 , X b , X b1 , X c , X c1 , X d , X d1 , R 1 , R 1a , R 2 , R 2a , R 3 , R 4 , R 4a , R 5 , R 6 , R 6a , R 7 , R 7a , R 8 , R 8a , R 9 , and R 10  are each selected independently from each other. 
     In another embodiment of the disclosure, the compound of the disclosure is selected from the exemplary species depicted in Examples 1 through 348 shown below. 
     Other embodiments of the present disclosure include the following: 
     (a) A pharmaceutical composition comprising an effective amount of a compound of general formula (I) or a compound of general formula (I′), or a compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and a pharmaceutically acceptable carrier. 
     (b) The pharmaceutical composition of (a), further comprising a second therapeutic agent selected from the group consisting of STING agonist compounds, anti-viral compounds, antigens, adjuvants, CTLA-4 and PD-1 pathway antagonists and other immunomodulatory agents, lipids, liposomes, peptides, anti-cancer and chemotherapeutic agents. 
     (c) A pharmaceutical combination that is (i) a compound of general formula (I) or a compound of general formula (I′), or a compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and (ii) a second therapeutic agent selected from the group consisting of STING agonist compounds, anti-viral compounds, antigens, adjuvants, CTLA-4 and PD-1 pathway antagonists and other immunomodulatory agents, lipids, liposomes, peptides, anti-cancer and chemotherapeutic agents; wherein the a compound of general formula (I) or compound of general formula (I′), or compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and the second therapeutic agent are each employed in an amount that renders the combination effective for inducing an immune response in a patient. 
     (e) A method of inducing an immune response in a patient, which comprises administering to the subject an effective amount of a compound of general formula (I) or a compound of general formula (I′), or a compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof. 
     (f) A method of inducing an immune response in a patient, which comprises administering to the subject an effective amount of a composition of (a), a composition of (b) or a combination of (c). 
     (g) A method of inducing STING-dependent type I interferon production in a patient, which comprises administering to the subject an effective amount of (a), a compound of general formula (I) or a compound of general formula (I′), or a compound of general formula (I″). 
     (h) A method of inducing STING-dependent type I interferon production in a patient, which comprises administering to the subject an effective amount of a composition of (a), a composition of (b) or a combination of (c). 
     (i) A method of inducing STING-dependent cytokine production in a patient, which comprises administering to the subject an effective amount of a compound of general formula (I) or a compound of general formula (I′), or a compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof. 
     (j) A method of inducing STING-dependent cytokine production in a patient, which comprises administering to the subject an effective amount of a composition of (a), a composition of (b) or a combination of (c). 
     (k) A method of treating a cell proliferation disorder in a subject, said method comprising administering a therapeutically effective amount of a compound of general formula (I) or a compound of general formula (I′), or a compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof to the subject; 
     (l) The method of (k), wherein the cell proliferation disorder is cancer. 
     (m). A method of treating a cell proliferation disorder in a subject, said method comprising administering a therapeutically effective amount of a pharmaceutical composition of (a), a composition of (b) or a combination of (c) to the subject. 
     (n) The method of (m), wherein the cell proliferation disorder is cancer. 
     The present disclosure also includes a compound of the present disclosure for use (i) in, (ii) as a medicament for, or (iii) in the preparation of a medicament for: (a) inducing an immune response in a patient, or (b) inducing a STING-dependent cytokine production in a patient. In these uses, the compounds of the present disclosure can optionally be employed in combination with one or more second therapeutic agents selected from STING agonist compounds, anti-viral compounds, antigens, adjuvants, CTLA-4 and PD-1 pathway antagonists and other immunomodulatory agents, lipids, liposomes, peptides, anti-cancer and chemotherapeutic agents. 
     Additional embodiments of the disclosure include the pharmaceutical compositions, combinations and methods set forth in (a)-(n) above and the uses set forth in the preceding paragraph, wherein the compound of the present disclosure employed therein is a compound of one of the embodiments, aspects, classes, sub-classes, or features of the compounds described above. In all of these embodiments, the compound may optionally be used in the form of a pharmaceutically acceptable salt, hydrate, solvate or prodrug as appropriate. 
     In the embodiments of the compound provided above, it is to be understood that each embodiment may be combined with one or more other embodiments, to the extent that such a combination provides a stable compound and is consistent with the description of the embodiments. It is further to be understood that the embodiments of compositions and methods provided as (a) through (n) above are understood to include all embodiments of the compounds, including such embodiments as result from combinations of embodiments. 
     The term “subject” (alternatively referred to herein as “patient”) as used herein refers to an animal, preferably a mammal, such as a human being, male or female, that has been the object of treatment, observation, or experiment. A subject also refers to one or more of cows, sheep, goats, horses, dogs, cats, rabbits, rats, mice, fish, and birds. In embodiments, the subject is human. 
     As used herein, the term “immune response” relates to any one or more of the following: specific immune response, non-specific immune response, both specific and non-specific response, innate response, primary immune response, adaptive immunity, secondary immune response, memory immune response, immune cell activation, immune cell proliferation, immune cell differentiation, and cytokine expression. In certain embodiments, the compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, is administered in conjunction with one or more additional therapeutic agents including vaccines intended to stimulate an immune response to one or more predetermined anti-viral compounds, antigens, adjuvants, CTLA-4 and PD-1 pathway antagonists and other immunomodulatory agents, lipids, liposomes, peptides, anti-cancer and chemotherapeutic agents, etc. In certain embodiments, the compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, is administered in conjunction with one or more additional compositions including vaccines intended to stimulate an immune response to one or more predetermined anti-viral compounds, antigens, adjuvants, CTLA-4 and PD-1 pathway antagonists and other immunomodulatory agents, lipids, liposomes, peptides, anti-cancer and chemotherapeutic agents, etc. 
     Compounds 
     The term “alkyl” refers to a monovalent straight or branched chain, saturated aliphatic hydrocarbon radical having a number of carbon atoms in the specified range. Thus, for example, “C 1-6  alkyl” (or “C 1 -C 6  alkyl”) refers to any of the hexyl alkyl and pentyl alkyl isomers as well as n-, iso-, sec- and tert-butyl, n- and iso-propyl, ethyl, and methyl. As another example, “C 1-4  alkyl” refers to n-, iso-, sec- and tert-butyl, n- and isopropyl, ethyl, and methyl. 
     As used herein, the term “alkylene” refers to a bivalent straight chain, saturated aliphatic hydrocarbon radical having a number of carbon atoms in the specified range. 
     As used herein, the term “alkenyl” refers to a monovalent straight or branched chain, unsaturated aliphatic hydrocarbon radical having a number of carbon atoms in the specified range and including one or more double bond. 
     As used herein, the term “alkenylene” refers to a bivalent straight chain, unsaturated aliphatic hydrocarbon radical having a number of carbon atoms in the specified range and including one or more double bond. 
     As used herein, the term “alkynyl” refers to a monovalent straight or branched chain, unsaturated aliphatic hydrocarbon radical having a number of carbon atoms in the specified range and including one or more triple bond. 
     As used herein, the term “alkynylene” refers to a bivalent straight chain, unsaturated aliphatic hydrocarbon radical having a number of carbon atoms in the specified range and including one or more triple bond. 
     The term “halogen” (or “halo”) refers to fluorine, chlorine, bromine, and iodine (alternatively referred to as fluoro, chloro, bromo, and iodo or F, Cl, Br, and I). 
     The term “haloalkyl” refers to an alkyl group as defined above in which one or more of the hydrogen atoms have been replaced with a halogen. Thus, for example, “C 1-6  haloalkyl” (or “C 1 -C 6  haloalkyl”) refers to a C 1  to C 6  linear or branched alkyl group as defined above with one or more halogen substituents. The term “fluoroalkyl” has an analogous meaning except the halogen substituents are restricted to fluoro. Suitable fluoroalkyls include the series (CH 2 ) 0-4 CF 3  (i.e., trifluoromethyl, 2,2,2-trifluoroethyl, 3,3,3-trifluoro-n-propyl, etc.). 
     As used herein, the term “haloalkenyl” refers to an alkenyl group as defined above in which one or more of the hydrogen atoms have been replaced with a halogen. 
     As used herein, the term “haloalkynyl” refers to an alkynyl group as defined above in which one or more of the hydrogen atoms have been replaced with a halogen. 
     As used herein, the term “spirocycle” or “spirocyclic ring” refers to a pendant cyclic group formed by substituents on a single atom. For example, in general formula (I), a spirocycle may be formed by R 2a  and R 3 . 
     Unless expressly stated to the contrary, all ranges cited herein are inclusive; i.e., the range includes the values for the upper and lower limits of the range as well as all values in between. As an example, temperature ranges, percentages, ranges of equivalents, and the like described herein include the upper and lower limits of the range and any value in the continuum there between. Numerical values provided herein, and the use of the term “about”, may include variations of ±1%, ±2%, ±3%, ±4%, ±5%, ±10%, ±15%, and ±20% and their numerical equivalents. 
     As used herein, the term “one or more” item includes a single item selected from the list as well as mixtures of two or more items selected from the list. 
     In the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″), the atoms may exhibit their natural isotopic abundances, or one or more of the atoms may be artificially enriched in a particular isotope having the same atomic number, but an atomic mass or mass number different from the atomic mass or mass number predominantly found in nature. The present disclosure is meant to include all suitable isotopic variations of the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″). For example, different isotopic forms of hydrogen (H) include protium ( 1 H) and deuterium ( 2 H). Protium is the predominant hydrogen isotope found in nature. Enriching for deuterium may afford certain therapeutic advantages, such as increasing in vivo half-life or reducing dosage requirements, or may provide a compound useful as a standard for characterization of biological samples. Isotopically-enriched compounds within general formula (I) can be prepared without undue experimentation by conventional techniques well known to those skilled in the art or by processes analogous to those described in the Schemes and Examples herein using appropriate isotopically-enriched reagents and/or intermediates. 
     In particular embodiments of the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″), the compounds are isotopically enriched with deuterium. In aspects of these embodiments, one or more of R 1 , R 1a , R 2 , R 2a , R 3 , R 4 , R 4a , R 5 , R 6 , R 6a , R 7 , R 7a , R 8 , R 8a , R 9 , and R 10  may be deuterium. 
     As shown in the general structural formulas and the structures of specific compounds as provided herein, a straight line at a chiral center includes both (R) and (S) stereoisomers and mixtures thereof. Also, unless otherwise specified (e.g., 100% purified compound), reference to a particular stereochemistry at a position provides a compound having the indicated stereochemistry, but does not exclude the presence of stereoisomers having different stereochemistry at the indicated position. 
     Recitation or depiction of a specific compound in the claims (i.e., a species) without a specific stereoconfiguration designation, or with such a designation for less than all chiral centers, is intended to encompass the racemate, racemic mixtures, each individual enantiomer, a diastereoisomeric mixture and each individual diastereomer of the compound where such forms are possible due to the presence of one or more asymmetric centers. The separation of a mixture of stereoisomers can be carried out at an intermediate step during the synthesis of a compound of general formula (I), a compound of general formula (I′), and/or a compound of general formula (I″), or it can be done on a final racemic product. Absolute stereochemistry may be determined by X-ray crystallography of crystalline products or crystalline intermediates, which are derivatized, if necessary, with a reagent containing a stereogenic center of known configuration. Alternatively, absolute stereochemistry may be determined by Vibrational Circular Dichroism (VCD) spectroscopy analysis. The present invention includes all such isomers, as well as salts, solvates (which includes hydrates) and solvated salts of such racemates, enantiomers, diastereomers and tautomers and mixtures thereof. 
     Those skilled in the art will recognize that chiral compounds, and in particular sugars, can be drawn in a number of different ways that are equivalent. Those skilled in the art will further recognize that the identity and regiochemical position of the substituents on ribose can vary widely and that the same principles of stereochemical equivalence apply regardless of substituent. Non-limiting examples of such equivalence include those exemplified below. 
                         
Salts
 
     Compounds described herein having appropriate functional groups can be provided as salts. Examples of such compounds are described herein by reference to possible salts. Such reference is for illustration only. Additional embodiments include salts of any compounds described herein having suitable groups. 
     Pharmaceutically acceptable salts can be used with compounds for treating patients. Non-pharmaceutical salts may, however, be useful in the preparation of intermediate compounds. 
     Pharmaceutically acceptable salts are suitable for administration to a patient, preferably, a human. Suitable salts include acid addition salts that may, for example, be formed by mixing a solution of a compound with a solution of a pharmaceutically acceptable acid such as hydrochloric acid, sulfuric acid, acetic acid, trifluoroacetic acid, or benzoic acid. Compounds carrying an acidic moiety can be mixed with suitable pharmaceutically acceptable salts to provide, for example, alkali metal salts (e.g., sodium or potassium salts), alkaline earth metal salts (e.g., calcium or magnesium salts), and salts formed with suitable organic ligands such as quaternary ammonium salts. Also, in the case of an acid (—COOH) or alcohol group being present, pharmaceutically acceptable esters can be employed to modify the solubility or hydrolysis characteristics of the compound. 
     Methods of Preparing Compounds 
     Several methods for preparing the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″), or pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof, are described in the following Schemes and Examples. Starting materials and intermediates are purchased from commercial sources, made from known procedures, or are otherwise illustrated. In some cases the order of carrying out the steps of the reaction schemes may be varied to facilitate the reaction or to avoid unwanted reaction products. 
     Method 1 
     One method for the preparation of examples of the disclosure is detailed in Scheme 1. This procedure was adequately modified from the previously reported procedure for cyclic dinucleotide synthesis (Barbara L. Gaffney et al.,  One - Flask Syntheses of c - di - GMP  and  the  [ Rp,Rp ]  and  [ Rp,Sp ]  Thiophosphate Analogues,  12 O RG . L ETT . 3269-3271 (2010)). The sequence starts with modified ribo-nucleoside with a nucleobase of which amino group was appropriately protected with an alkyl or phenyl carbonyl group, a phosphoramidite functionality at 2′-O position, and DMTr ether at 5′-O position. It was treated with aqueous TFA/pyridine condition and subsequently t-butylamine to convert the 2′-phosphoramidite moiety to an H-phosphonate. Then, DMTr ether was removed under acidic condition. The resulting 5′-hydroxyl group was reacted with 3′-phosphoramidites of fully protected second modified ribo-nucleoside to give a cyclized compound. It was immediately oxidized with t-butyl hydroperoxide. Then, the 5′-hydroxyl group of the second ribo-nucleoside was deprotected with dichloroacetic acid. Using 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphinane 2-oxide as a coupling reagent, the H-phosphonate at 2′-O of the first ribo-nucleoside was reacted with 5′-OH of the second ribo-nucleoside to give a cyclic product. It was immediately oxidized with aqueous iodine. Treatment with t-butylamine and methylamine plus fluoride anion in case silyl protection was used provided the desired cyclic dinucleotide 1G. 
                                           
Method 2
 
     Another method for the preparation of examples of the disclosure is detailed in Scheme 2. This procedure was modified from Scheme 1. The sequence starts with modified ribo-nucleoside with a nucleobase of which amino group was appropriately protected with an alkyl or phenyl carbonyl group, a phosphoramidite functionality at 2′-O position, and DMTr ether at 5′-O position. It was treated with aqueous TFA/pyridine condition and subsequently t-butylamine to convert the 2′-phosphoramidite moiety to an H-phosphonate. Then, DMTr ether was removed under acidic condition. The resulting 5′-hydroxyl group was reacted with 3′-phosphoramidites of fully protected second modified ribo-nucleoside to give a cyclized compound. It was immediately thioated with (E)-N,N-dimethyl-N′-(3-thioxo-3H-1,2,4-dithiazol-5-yl)formimidamide. Then, the 5′-hydroxyl group of the second ribo-nucleoside was deprotected with dichloroacetic acid. Using 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphinane 2-oxide as a coupling reagent, the H-phosphonate at 2′-O of the first ribo-nucleoside was reacted with 5′-OH of the second ribo-nucleoside to give a cyclic product. It was immediately thioated with 3H-benzo[c][1,2]dithiol-3-one. Treatment with t-butylamine and methylamine plus fluoride anion in case silyl protection was used provided the desired cyclic dinucleotide diphosphorothioate 2G. 
                                           
Methods of Use
 
     Compounds described herein having therapeutic applications, such as the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″), and the compounds of the Examples 1 through 348, can be administered to a patient for the purpose of inducing an immune response, inducing a STING-dependent cytokine production and/or inducing anti-tumor activity. The term “administration” and variants thereof (e.g., “administering” a compound) means providing the compound to the individual in need of treatment. When a compound is provided in combination with one or more other active agents (e.g., antiviral agents useful for treating HCV infection or anti-tumor agents for treating cancers), “administration” and its variants are each understood to include concurrent and sequential provision of the compound or salt and other agents. 
     The compounds disclosed herein are STING agonists and inhibitors of viral replication. These compounds are potentially useful in treating diseases or disorders including, but not limited to, cell proliferation disorders, such as cancer. 
     Cell-proliferation disorders include, but are not limited to, cancer. Examples of such cancers include, but are not limited to, Acute Lymphoblastic Leukemia; Acute Myeloid Leukemia; Adrenocortical Carcinoma; AIDS-Related Lymphoma; AIDS-Related Malignancies; Anal Cancer; Astrocytoma; Bile Duct Cancer; Bladder Cancer; Bone Cancer, Osteosarcoma/Malignant Fibrous Histiocytoma; Brain Stem Glioma; Brain Tumor, Cerebellar Astrocytoma; Brain Tumor, Cerebral Astrocytoma/Malignant Glioma; Brain Tumor, Ependymoma; Brain Tumor, Medulloblastoma; Brain Tumor, Supratentorial Primitive Neuroectodermal Tumors; Brain Tumor, Visual Pathway and Hypothalamic Glioma; Breast Cancer; Bronchial Adenomas/Carcinoids; Carcinoid Tumor; Carcinoid Tumor, Gastrointestinal; Carcinoma, Adrenocortical; Carcinoma, Islet Cell; Central Nervous System Lymphoma, Primary; Cerebral Astrocytoma/Malignant Glioma; Cervical Cancer; Chronic Lymphocytic Leukemia; Chronic Myelogenous Leukemia; Chronic Myeloproliferative Disorders; Clear Cell Sarcoma of Tendon Sheaths; Colon Cancer; Colorectal Cancer; Cutaneous T-Cell Lymphoma; Endometrial Cancer; Ependymoma; Epithelial Cancer, Ovarian; Esophageal Cancer; Esophageal Cancer; Ewing&#39;s Family of Tumors; Extracranial Germ Cell Tumor; Extrahepatic Bile Duct Cancer; Eye Cancer, Intraocular Melanoma; Eye Cancer, Retinoblastoma; Gallbladder Cancer; Gastric (Stomach) Cancer; Gastrointestinal Carcinoid Tumor; Germ Cell Tumor, Extracranial, Childhood; Germ Cell Tumor, Extragonadal; Germ Cell Tumor, Ovarian; Gestational Trophoblastic Tumor; Glioma, Childhood Brain Stem; Glioma, Childhood Visual Pathway and Hypothalamic; Hairy Cell Leukemia; Head and Neck Cancer; Hepatocellular (Liver) Cancer; Hodgkin&#39;s Lymphoma; Hypopharyngeal Cancer; Hypothalamic and Visual Pathway Glioma; Intraocular Melanoma; Islet Cell Carcinoma (Endocrine Pancreas); Kaposi&#39;s Sarcoma; Kidney Cancer; Laryngeal Cancer; Leukemia, Acute Lymphoblastic; Leukemia, Acute Myeloid; Leukemia, Chronic Lymphocytic; Leukemia, Chronic Myelogenous; Leukemia, Hairy Cell; Lip and Oral Cavity Cancer; Liver Cancer; Lung Cancer, Non-Small Cell; Lung Cancer, Small Cell; Lymphoblastic Leukemia; Lymphoma, AIDS-Related; Lymphoma, Central Nervous System (Primary); Lymphoma, Cutaneous T-Cell; Lymphoma, Hodgkin&#39;s; Lymphoma, Hodgkin&#39;s During Pregnancy; Lymphoma, Non-Hodgkin&#39;s; Lymphoma, Primary Central Nervous System; Macroglobulinemia, Waldenstrom&#39;s; Male Breast Cancer; Malignant Mesothelioma; Malignant Thymoma; Medulloblastoma, Childhood; Melanoma; Melanoma, Intraocular; Merkel Cell Carcinoma; Mesothelioma, Malignant; Metastatic Squamous Neck Cancer with Occult Primary; Multiple Endocrine Neoplasia Syndrome, Childhood; Multiple Myeloma/Plasma Cell Neoplasm; Mycosis Fungoides; Myelodysplastic Syndromes; Myelogenous Leukemia, Chronic; Myeloid Leukemia; Myeloma, Multiple; Myeloproliferative Disorders, Chronic; Nasal Cavity and Paranasal Sinus Cancer; Nasopharyngeal Cancer; Neuroblastoma; Non-Hodgkin&#39;s Lymphoma; Non-Small Cell Lung Cancer; Oral Cancer; Oral Cavity and Lip Cancer; Oropharyngeal Cancer; steosarcoma/Malignant Fibrous Histiocytoma of Bone; Ovarian Epithelial Cancer; Ovarian Germ Cell Tumor; Ovarian Low Malignant Potential Tumor; Pancreatic Cancer; Paranasal Sinus and Nasal Cavity Cancer; Parathyroid Cancer; Penile Cancer; Pheochromocytoma; Pineal and Supratentorial Primitive Neuroectodermal Tumors; Pituitary Tumor; Plasma Cell Neoplasm/Multiple Myeloma; Pleuropulmonary Blastoma; Pregnancy and Breast Cancer; Pregnancy and Hodgkin&#39;s Lymphoma; Pregnancy and Non-Hodgkin&#39;s Lymphoma; Primary Central Nervous System Lymphoma; Primary Liver Cancer; Prostate Cancer; Rectal Cancer; Renal Cell (Kidney) Cancer; Renal Pelvis and Ureter, Transitional Cell Cancer; Retinoblastoma; Rhabdomyosarcoma; Salivary Gland Cancer; Sarcoma, Ewing&#39;s Family of Tumors; Sarcoma, Kaposi&#39;s; Sarcoma (Osteosarcoma)/Malignant Fibrous Histiocytoma of Bone; Sarcoma, Soft Tissue; Sezary Syndrome; Skin Cancer; Skin Cancer (Melanoma); Skin Carcinoma, Merkel Cell; Small Cell Lung Cancer; Small Intestine Cancer; Soft Tissue Sarcoma; Squamous Neck Cancer with Occult Primary, Metastatic; Stomach (Gastric) Cancer; Supratentorial Primitive Neuroectodermal Tumors; T-Cell Lymphoma, Cutaneous; Testicular Cancer; Thymoma, Malignant; Thyroid Cancer; Transitional Cell Cancer of the Renal Pelvis and Ureter; Trophoblastic Tumor, Gestational; Ureter and Renal Pelvis, Transitional Cell Cancer; Urethral Cancer; Uterine Sarcoma; Vaginal Cancer; Visual Pathway and Hypothalamic Glioma; Vulvar Cancer; Waldenstrom&#39;s Macro globulinemia; and Wilms&#39; Tumor. 
     In one embodiment, the cancer is brain cancer, such as an astrocytic tumor (e.g., pilocytic astrocytoma, subependymal giant-cell astrocytoma, diffuse astrocytoma, pleomorphic xanthoastrocytoma, anaplastic astrocytoma, astrocytoma, giant cell glioblastoma, glioblastoma, secondary glioblastoma, primary adult glioblastoma, and primary pediatric glioblastoma); oligodendroglial tumor (e.g., oligodendroglioma, and anaplastic oligodendroglioma); oligoastrocytic tumor (e.g., oligoastrocytoma, and anaplastic oligoastrocytoma); ependymoma (e.g., myxopapillary ependymoma, and anaplastic ependymoma); medulloblastoma; primitive neuroectodermal tumor, schwannoma, meningioma, atypical meningioma, anaplastic meningioma; and pituitary adenoma. In another embodiment, the brain cancer is glioma, glioblastoma multiforme, paraganglioma, or suprantentorial primordial neuroectodermal tumors (sPNET). 
     In another embodiment, the cancer is leukemia, such as acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), chronic myelogenous leukemia (CML), myeloproliferative neoplasm (MPN), post-MPN AML, post-MDS AML, del(5q)-associated high risk MDS or AML, blast-phase chronic myelogenous leukemia, angioimmunoblastic lymphoma, and acute lymphoblastic leukemia. 
     In one embodiment, the cancer is skin cancer, including melanoma. In another embodiment, the cancer is prostate cancer, breast cancer, thyroid cancer, colon cancer, or lung cancer. In another embodiment, the cancer is sarcoma, including central chondrosarcoma, central and periosteal chondroma, and fibrosarcoma. In another embodiment, the cancer is cholangiocarcinoma. 
     As used herein, the terms “treatment” and “treating” refer to all processes wherein there may be a slowing, interrupting, arresting, controlling, or stopping of the progression of a disease or disorder described herein. The terms do not necessarily indicate a total elimination of all disease or disorder symptoms. 
     The terms “administration of” and or “administering” a compound should be understood to include providing a compound described herein, or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof, and compositions of the foregoing to a subject. 
     The amount of a compound administered to a subject is an amount sufficient to induce an immune response and/or to induce STING-dependent type I interferon production in the subject. In an embodiment, the amount of a compound can be an “effective amount” or “therapeutically effective amount,” wherein the subject compound is administered in an amount that will elicit, respectively, a biological or medical (i.e., intended to treat) response of a tissue, system, animal or human that is being sought by a researcher, veterinarian, medical doctor or other clinician. An effective amount does not necessarily include considerations of toxicity and safety related to the administration of a compound. 
     An effective amount of a compound will vary with the particular compound chosen (e.g., considering the potency, efficacy, and/or half-life of the compound); the route of administration chosen; the condition being treated; the severity of the condition being treated; the age, size, weight, and physical condition of the subject being treated; the medical history of the subject being treated; the duration of the treatment; the nature of a concurrent therapy; the desired therapeutic effect; and like factors and can be routinely determined by the skilled artisan. 
     The compounds disclosed herein may be administered by any suitable route including oral and parenteral administration. Parenteral administration is typically by injection or infusion and includes intravenous, intramuscular, and subcutaneous injection or infusion. 
     The compounds disclosed herein may be administered once or according to a dosing regimen wherein a number of doses are administered at varying intervals of time for a given period of time. For example, doses may be administered one, two, three, or four times per day. Doses may be administered until the desired therapeutic effect is achieved or indefinitely to maintain the desired therapeutic effect. Suitable dosing regimens for a compound disclosed herein depend on the pharmacokinetic properties of that compound, such as absorption, distribution and half-life which can be determined by a skilled artisan. In addition, suitable dosing regimens, including the duration such regimens are administered, for a compound disclosed herein depend on the disease or condition being treated, the severity of the disease or condition, the age and physical condition of the subject being treated, the medical history of the subject being treated, the nature of concurrent therapy, the desired therapeutic effect, and like factors within the knowledge and expertise of the skilled artisan. It will be further understood by such skilled artisans that suitable dosing regimens may require adjustment given an individual subject&#39;s response to the dosing regimen or over time as the individual subject needs change. Typical daily dosages may vary depending upon the particular route of administration chosen. 
     One embodiment of the present disclosure provides for a method of treating a cell proliferation disorder comprising administration of a therapeutically effective amount of a compound of general formula (I), a compound of general formula (I′), or a compound of general formula (I″) to a subject in need of treatment thereof. In one embodiment, the cell proliferation disorder is cancer. 
     In one embodiment, the cancer is brain cancer, leukemia, skin cancer, prostate cancer, thyroid cancer, colon cancer, lung cancer or sarcoma. In another embodiment the cancer is selected from the group consisting of glioma, glioblastoma multiforme, paraganglioma, suprantentorial primordial neuroectodermal tumors, acute myeloid leukemia, myelodysplastic syndrome, chronic myelogenous leukemia, melanoma, breast, prostate, thyroid, colon, lung, central chondrosarcoma, central and periosteal chondroma tumors, fibrosarcoma, and cholangiocarcinoma. 
     In one embodiment, disclosed herein is the use of a compound of general formula (I), compound of general formula (I′), and/or compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof, in a therapy. The compound may be useful in a method of inducing an immune response and/or inducing STING-dependent type I interferon production in a subject, such as a mammal in need of such inhibition, comprising administering an effective amount of the compound to the subject. 
     In one embodiment, disclosed herein is a pharmaceutical composition comprising at least one compound of general formula (I), compound of general formula (I′), and/or compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof, for use in potential treatment to induce an immune response and/or to induce STING-dependent type I interferon production. 
     In one embodiment, disclosed herein is the use of a compound of general formula (I), compound of general formula (I′), and/or compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate or prodrug thereof, in the manufacture of a medicament for the treatment to induce an immune response and/or to induce STING-dependent type I interferon production. In one embodiment, the disease or disorder to be treated is a cell proliferation disorder. In another embodiment, the cell proliferation disorder is cancer. In another embodiment, the cancer is brain cancer, leukemia, skin cancer, breast, prostate cancer, thyroid cancer, colon cancer, lung cancer, or sarcoma. In another embodiment, the cancer is glioma, glioblastoma multiforme, paraganglioma, suprantentorial primordial neuroectodermal tumors, acute myeloid leukemia, myelodysplastic syndrome, chronic myelogenous leukemia, melanoma, breast, prostate, thyroid, colon, lung, central chondrosarcoma, central and periosteal chondroma tumors, fibrosarcoma, and/or cholangiocarcinoma. 
     Compositions 
     The term “composition” as used herein is intended to encompass a dosage form comprising a specified compound in a specified amount, as well as any dosage form which results, directly or indirectly, from combination of a specified compound in a specified amount. 
     Such term is intended to encompass a dosage form comprising a compound of general formula (I), a compound of general formula (I′), and/or a compound of general formula (I″), or a pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and one or more pharmaceutically acceptable carriers or excipients. Accordingly, the compositions of the present disclosure encompass any composition made by admixing a compound of the present disclosure and one or more pharmaceutically acceptable carrier or excipients. By “pharmaceutically acceptable”, it is meant the carriers or excipients are compatible with the compound disclosed herein and with other ingredients of the composition. 
     For the purpose of inducing an immune response and/or inducing a STING-dependent type I interferon production, the compounds, optionally in the form of a salt, hydrate, solvate or prodrug, can be administered by means that produces contact of the active agent with the agent&#39;s site of action. They can be administered by conventional means available for use in conjunction with pharmaceuticals, either as individual therapeutic agents or in a combination of therapeutic agents. They can be administered alone, but typically are administered with a pharmaceutical carrier selected on the basis of the chosen route of administration and standard pharmaceutical practice. 
     In one embodiment, disclosed herein is a composition comprising a compound of general formula (I), a compound of general formula (I′), and/or a compound of general formula (I″), or a pharmaceutically acceptable salt thereof, and one or more pharmaceutically acceptable carriers or excipients. The composition may be prepared and packaged in bulk form wherein an effective amount of a compound of the disclosure can be extracted and then given to a subject, such as with powders or syrups. Alternatively, the composition may be prepared and packaged in unit dosage form wherein each physically discrete unit contains an effective amount of a compound of general formula (I), a compound of general formula (I′), and/or a compound of general formula (I″). 
     The compounds disclosed herein and a pharmaceutically acceptable carrier or excipient(s) will typically be formulated into a dosage form adapted for administration to a subject by a desired route of administration. For example, dosage forms include those adapted for (1) oral administration, such as tablets, capsules, caplets, pills, troches, powders, syrups, elixirs, suspensions, solutions, emulsions, sachets, and cachets; and (2) parenteral administration, such as sterile solutions, suspensions, and powders for reconstitution. Suitable pharmaceutically acceptable carriers or excipients will vary depending upon the particular dosage form chosen. In addition, suitable pharmaceutically acceptable carriers or excipients may be chosen for a particular function that they may serve in the composition. For example, certain pharmaceutically acceptable carriers or excipients may be chosen for their ability to facilitate the production of uniform dosage forms. Certain pharmaceutically acceptable carriers or excipients may be chosen for their ability to facilitate the production of stable dosage forms. Certain pharmaceutically acceptable carriers or excipients may be chosen for their ability to facilitate the carrying or transporting of a compound disclosed herein, once administered to the subject, from one organ or portion of the body to another organ or another portion of the body. Certain pharmaceutically acceptable carriers or excipients may be chosen for their ability to enhance patient compliance. 
     Suitable pharmaceutically acceptable excipients include the following types of excipients: diluents, lubricants, binders, disintegrants, fillers, glidants, granulating agents, coating agents, wetting agents, solvents, co-solvents, suspending agents, emulsifiers, sweeteners, flavoring agents, flavor masking agents, coloring agents, anti-caking agents, hemectants, chelating agents, plasticizers, viscosity increasing agents, antioxidants, preservatives, stabilizers, surfactants, and buffering agents. 
     A skilled artisan possesses the knowledge and skill in the art to select suitable pharmaceutically acceptable carriers and excipients in appropriate amounts for the use in the disclosure. In addition, there are a number of resources available to the skilled artisan, which describe pharmaceutically acceptable carriers and excipients and may be useful in selecting suitable pharmaceutically acceptable carriers and excipients. Examples include Remington&#39;s Pharmaceutical Sciences (Mack Publishing Company), The Handbook of Pharmaceutical Additives (Gower Publishing Limited), and The Handbook of Pharmaceutical Excipients (the American Pharmaceutical Association and the Pharmaceutical Press). 
     The compositions of the disclosure are prepared using techniques and methods known to those skilled in the art. Some methods commonly used in the art are described in Remington&#39;s Pharmaceutical Sciences (Mack Publishing Company). 
     In one embodiment, the disclosure is directed to a solid oral dosage form such as a tablet or capsule comprising an effective amount of a compound of the disclosure and a diluent or filler. Suitable diluents and fillers include lactose, sucrose, dextrose, mannitol, sorbitol, starch (e.g., corn starch, potato starch, and pre-gelatinized starch), cellulose and its derivatives, (e.g., microcrystalline cellulose), calcium sulfate, and dibasic calcium phosphate. The oral solid dosage form may further comprise a binder. Suitable binders include starch (e.g., corn starch, potato starch, and pre-gelatinized starch) gelatin, acacia, sodium alginate, alginic acid, tragacanth, guar gum, povidone, and cellulose and its derivatives (e.g., microcrystalline cellulose). The oral solid dosage form may further comprise a disintegrant. Suitable disintegrants include crospovidone, sodium starch glycolate, croscarmelose, alginic acid, and sodium carboxymethyl cellulose. The oral solid dosage form may further comprise a lubricant. Suitable lubricants include stearic acid, magnesium stearate, calcium stearate, and talc. 
     Where appropriate, dosage unit formulations for oral administration can be microencapsulated. The composition can also be prepared to prolong or sustain the release as, for example, by coating or embedding particulate material in polymers, wax, or the like. 
     The compounds disclosed herein may also be coupled with soluble polymers as targetable drug carriers. Such polymers can include polyvinylpyrrolidone, pyrancopolymer, polyhydroxypropylmethacrylamidephenol, polyhydroxyethylaspartamidephenol, or polyethyleneoxidepolylysine substituted with palmitoyl residues. Furthermore, the compounds of the disclosure may be coupled to a class of biodegradable polymers useful in achieving controlled release of a drug, for example polylactic acid, polepsilon caprolactone, polyhydroxy butyric acid, polyorthoesters, polyacetals, polydihydropyrans, polycyanacrylates and cross-linked or amphipathic block copolymers of hydrogels. 
     In one embodiment, the disclosure is directed to a liquid oral dosage form. Oral liquids such as solution, syrups and elixirs can be prepared in dosage unit form so that a given quantity contains a predetermined amount of a compound disclosed herein. Syrups can be prepared by dissolving the compound of the disclosure in a suitably flavored aqueous solution; while elixirs are prepared through the use of a non-toxic alcoholic vehicle. Suspensions can be formulated by dispersing a compound disclosed herein in a non-toxic vehicle. Solubilizers and emulsifiers such as ethoxylated isostearyl alcohols and polyoxy ethylene sorbitol ethers, preservatives, flavor additives such as peppermint oil or other natural sweeteners or saccharin or other artificial sweeteners and the like can also be added. 
     In one embodiment, the disclosure is directed to compositions for parenteral administration. Compositions adapted for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats, and solutes that render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions that may include suspending agents and thickening agents. The compositions may be presented in unit-dose or multi-dose containers, for example sealed ampoules and vials, and may be stored in a freeze dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets. 
     Combinations 
     The compounds of general formula (I), compounds of general formula (I′), and/or compounds of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, may be administered in combination with one or more additional therapeutic agents. In embodiments, one or more a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and the one or more additional therapeutic agents may be co-adminstered. The additional therapeutic agent(s) may be administered in a single dosage form with the compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, or the additional therapeutic agent(s) may be administered in separate dosage form(s) from the dosage form containing the compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof. The additional therapeutic agent(s) may be one or more agents selected from the group consisting of STING agonist compounds, anti-viral compounds, antigens, adjuvants, anti-cancer agents, CTLA-4, LAG-3 and PD-1 pathway antagonists, lipids, peptides, cytotoxic agents, chemotherapeutic agents, immunomodulatory cell lines, checkpoint inhibitors, vascular endothelial growth factor (VEGF) receptor inhibitors, topoisomerase II inhibitors, smoothen inhibitors, alkylating agents, anti-tumor antibiotics, anti-metabolites, retinoids, and immunomodulatory agents including but not limited to anti-cancer vaccines. It will be understood the descriptions of the above additional therapeutic agents may be overlapping. It will also be understood that the treatment combinations are subject to optimization, and it is understood that the best combination to use of the compounds of general formula (I), compounds of general formula (I′), or compounds of general formula (I″) and one or more additional therapeutic agents will be determined based on the individual patient needs. 
     A compound disclosed herein may be used in combination with one or more other active agents, including but not limited to, other anti-cancer agents that are used in the prevention, treatment, control, amelioration, or reduction of risk of a particular disease or condition (e.g., cell proliferation disorders). In one embodiment, a compound disclosed herein is combined with one or more other anti-cancer agents for use in the prevention, treatment, control amelioration, or reduction of risk of a particular disease or condition for which the compounds disclosed herein are useful. Such other active agents may be administered, by a route and in an amount commonly used therefor, contemporaneously or sequentially with a compound of the present disclosure. 
     When a compound disclosed herein is used contemporaneously with one or more other active agents, a composition containing such other active agents in addition to the compound disclosed herein is contemplated. Accordingly, the compositions of the present disclosure include those that also contain one or more other active ingredients, in addition to a compound disclosed herein. A compound disclosed herein may be administered either simultaneously with, or before or after, one or more other therapeutic agent(s). A compound disclosed herein may be administered separately, by the same or different route of administration, or together in the same pharmaceutical composition as the other agent(s). 
     Products provided as combinations may include a composition comprising a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and one or more other active agent(s) together in the same pharmaceutical composition, or may include a composition comprising a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and a composition comprising one or more other therapeutic agent(s) in separate form, e.g. in the form of a kit or in any form designed to enable separate administration either concurrently or on separate dosing schedules. 
     The weight ratio of a compound disclosed herein to a second active agent may be varied and will depend upon the effective dose of each agent. Generally, an effective dose of each will be used. Combinations of a compound disclosed herein and other active agents will generally also be within the aforementioned range, but in each case, an effective dose of each active agent should be used. In such combinations, the compound disclosed herein and other active agents may be administered separately or in conjunction. In addition, the administration of one element may be prior to, concurrent to, or subsequent to the administration of other agent(s). 
     In one embodiment, this disclosure provides a composition comprising a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, and at least one other therapeutic agent as a combined preparation for simultaneous, separate or sequential use in therapy. In one embodiment, the therapy is the treatment of a cell proliferation disorder, such as cancer. 
     In one embodiment, the disclosure provides a kit comprising two or more separate pharmaceutical compositions, at least one of which contains a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof. In one embodiment, the kit comprises means for separately retaining said compositions, such as a container, divided bottle, or divided foil packet. An example of such a kit is a blister pack, as typically used for the packaging of tablets, capsules, and the like. 
     A kit of this disclosure may be used for administration of different dosage forms, for example, oral and parenteral, for administration of the separate compositions at different dosage intervals, or for titration of the separate compositions against one another. To assist with compliance, a kit of the disclosure typically comprises directions for administration. 
     Disclosed herein is a use of a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, for treating a cell proliferation disorder, wherein the medicament is prepared for administration with another active agent. The disclosure also provides the use of another active agent for treating a cell proliferation disorder, wherein the medicament is administered with a compound of general formula (I). 
     The disclosure also provides the use of a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof, for treating a cell proliferation disorder, wherein the patient has previously (e.g., within 24 hours) been treated with another active agent. The disclosure also provides the use of another therapeutic agent for treating a cell proliferation disorder, wherein the patient has previously (e.g., within 24 hours) been treated with a compound of general formula (I), compound of general formula (I′), or compound of general formula (I″), or pharmaceutically acceptable salt, hydrate, solvate, or prodrug thereof. The second agent may be applied a week, several weeks, a month, or several months after the administration of a compound disclosed herein. 
     STING agonist compounds that may be used in combination with the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″) disclosed herein include but are not limited to cyclic di-nucleotide compounds. 
     Anti-viral compounds that may be used in combination with the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″) disclosed herein include hepatitis B virus (HBV) inhibitors, hepatitis C virus (HCV) protease inhibitors, HCV polymerase inhibitors, HCV NS4 Å inhibitors, HCV NS5 Å inhibitors, HCV NS5b inhibitors, and human immunodeficiency virus (HIV) inhibitors. 
     Antigens and adjuvants that may be used in combination with the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″) disclosed herein include B7 costimulatory molecule, interleukin-2, interferon-y, GM-CSF, CTLA-4 antagonists, OX-40/OX-40 ligand, CD40/CD40 ligand, sargramostim, levamisol, vaccinia virus, Bacille Calmette-Guerin (BCG), liposomes, alum, Freund&#39;s complete or incomplete adjuvant, detoxified endotoxins, mineral oils, surface active substances such as lipolecithin, pluronic polyols, polyanions, peptides, and oil or hydrocarbon emulsions. Adjuvants, such as aluminum hydroxide or aluminum phosphate, can be added to increase the ability of the vaccine to trigger, enhance, or prolong an immune response. Additional materials, such as cytokines, chemokines, and bacterial nucleic acid sequences, like CpG, a toll-like receptor (TLR) 9 agonist as well as additional agonists for TLR 2, TLR 4, TLR 5, TLR 7, TLR 8, TLR9, including lipoprotein, LPS, monophosphoryllipid A, lipoteichoic acid, imiquimod, resiquimod, and in addition retinoic acid-inducible gene I (RIG-I) agonists such as poly I:C, used separately or in combination with the described compositions are also potential adjuvants. 
     CLTA-4 and PD-1 pathways are important negative regulators of immune response. Activated T-cells upregulate CTLA-4, which binds on antigen-presenting cells and inhibits T-cell stimulation, IL-2 gene expression, and T-cell proliferation; these anti-tumor effects have been observed in mouse models of colon carcinoma, metastatic prostate cancer, and metastatic melanoma. PD-1 binds to active T-cells and suppresses T-cell activation; PD-1 antagonists have demonstrated anti-tumor effects as well. CTLA-4 and PD-1 pathway antagonists that may be used in combination with the compounds of general formula (I) disclosed herein include ipilimumab, tremelimumab, nivolumab, pembrolizumab, CT-011, AMP-224, and MDX-1106. 
     “PD-1 antagonist” or “PD-1 pathway antagonist” means any chemical compound or biological molecule that blocks binding of PD-L1 expressed on a cancer cell to PD-1 expressed on an immune cell (T-cell, B-cell, or NKT-cell) and preferably also blocks binding of PD-L2 expressed on a cancer cell to the immune-cell expressed PD-1. Alternative names or synonyms for PD-1 and its ligands include: PDCD1, PD1, CD279, and SLEB2 for PD-1; PDCD1 L1, PDL1, B7H1, B7-4, CD274, and B7-H for PD-L1; and PDCD1 L2, PDL2, B7-DC, Btdc, and CD273 for PD-L2. In any of the treatment method, medicaments and uses of the present disclosure in which a human individual is being treated, the PD-1 antagonist blocks binding of human PD-L1 to human PD-1, and preferably blocks binding of both human PD-L1 and PD-L2 to human PD-1. Human PD-1 amino acid sequences can be found in NCBI Locus No.: NP_005009. Human PD-L1 and PD-L2 amino acid sequences can be found in NCBI Locus No.: NP_054862 and NP_079515, respectively. 
     PD-1 antagonists useful in any of the treatment method, medicaments and uses of the present disclosure include a monoclonal antibody (mAb), or antigen binding fragment thereof, which specifically binds to PD-1 or PD-L1, and preferably specifically binds to human PD-1 or human PD-L1. The mAb may be a human antibody, a humanized antibody, or a chimeric antibody and may include a human constant region. In some embodiments, the human constant region is selected from the group consisting of IgG1, IgG2, IgG3, and IgG4 constant regions, and in preferred embodiments, the human constant region is an IgG1 or IgG4 constant region. In some embodiments, the antigen binding fragment is selected from the group consisting of Fab, Fab′-SH, F(ab′) 2 , scFv, and Fv fragments. 
     Examples of mAbs that bind to human PD-1, and useful in the treatment method, medicaments and uses of the present disclosure, are described in U.S. Pat. Nos. 7,488,802, 7,521,051, 8,008,449, 8,354,509, and 8,168,757, PCT International Patent Application Publication Nos. WO2004/004771, WO2004/072286, and WO2004/056875, and U.S. Patent Application Publication No. US2011/0271358. 
     Examples of mAbs that bind to human PD-L1, and useful in the treatment method, medicaments and uses of the present disclosure, are described in PCT International Patent Application Nos. WO2013/019906 and WO2010/077634 A1 and in U.S. Pat. No. 8,383,796. Specific anti-human PD-L1 mAbs useful as the PD-1 antagonist in the treatment method, medicaments and uses of the present disclosure include MPDL3280 Å, BMS-936559, MEDI4736, MSB0010718C, and an antibody that comprises the heavy chain and light chain variable regions of SEQ ID NO:24 and SEQ ID NO:21, respectively, of WO2013/019906. 
     Other PD-1 antagonists useful in any of the treatment method, medicaments, and uses of the present disclosure include an immune-adhesion that specifically binds to PD-1 or PD-L1, and preferably specifically binds to human PD-1 or human PD-L1, e.g., a fusion protein containing the extracellular or PD-1 binding portion of PD-L1 or PD-L2 fused to a constant region such as an Fc region of an immunoglobulin molecule. Examples of immune-adhesion molecules that specifically bind to PD-1 are described in PCT International Patent Application Publication Nos. WO2010/027827 and WO2011/066342. Specific fusion proteins useful as the PD-1 antagonist in the treatment method, medicaments, and uses of the present disclosure include AMP-224 (also known as B7-DCIg), which is a PD-L2-FC fusion protein and binds to human PD-1. 
     Examples of cytotoxic agents that may be used in combination with the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″), or pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof, disclosed herein include, but are not limited to, arsenic trioxide (sold under the tradename TRISENOX®), asparaginase (also known as L-asparaginase, and Erwinia L-asparaginase, sold under the tradenames ELSPAR® and KIDROLASE®). 
     Chemotherapeutic agents that may be used in combination with the compounds of general formula (I), compounds of general formula (I′), and compounds of general formula (I″), or pharmaceutically acceptable salts, hydrates, solvates, or prodrugs thereof, disclosed herein include abiraterone acetate, altretamine, anhydrovinblastine, auristatin, bexarotene, bicalutamide, BMS 184476, 2,3,4,5,6-pentafluoro-N-(3-fluoro-4-methoxyphenyl)benzene sulfonamide, bleomycin, N,N-dimethyl-L-valyl-L-valyl-N-methyl-L-valyl-L-proly-1-Lproline-tbutylamide, cachectin, cemadotin, chlorambucil, cyclophosphamide, 3′,4′-didehydro-4′deoxy-8′-norvin-caleukoblastine, docetaxol, doxetaxel, cyclophosphamide, carboplatin, carmustine, cisplatin, cryptophycin, cyclophosphamide, cytarabine, dacarbazine (DTIC), dactinomycin, daunorubicin, decitabine dolastatin, doxorubicin (adriamycin), etoposide, 5-fluorouracil, finasteride, flutamide, hydroxyurea and hydroxyureataxanes, ifosfamide, liarozole, lonidamine, lomustine (CCNU), MDV3100, mechlorethamine (nitrogen mustard), melphalan, mivobulin isethionate, rhizoxin, sertenef, streptozocin, mitomycin, methotrexate, taxanes, nilutamide, nivolumab, onapristone, paclitaxel, pembrolizumab, prednimustine, procarbazine, RPR109881, stramustine phosphate, tamoxifen, tasonermin, taxol, tretinoin, vinblastine, vincristine, vindesine sulfate, and vinflunine. 
     Examples of vascular endothelial growth factor (VEGF) receptor inhibitors include, but are not limited to, bevacizumab (sold under the trademark AVASTIN by Genentech/Roche), axitinib (described in PCT International Patent Publication No. WO1/002369), Brivanib Alaninate ((S)—((R)-1-(4-(4-Fluoro-2-methyl-1H-indol-5-yloxy)-5-methylpyrrolo[2,1-f][1,2,4]triazin-6-yloxy)propan-2-yl)2-aminopropanoate, also known as BMS-582664), motesanib (N-(2,3-dihydro-3,3-dimethyl-1H-indol-6-yl)-2-[(4-pyridinylmethyl)amino]-3-pyridinecarboxamide. and described in PCT International Patent Application Publication No. WO02/068470), pasireotide (also known as SO 230, and described in PCT International Patent Publication No. WO02/010192), and sorafenib (sold under the tradename NEXAVAR). 
     Examples of topoisomerase II inhibitors, include but are not limited to, etoposide (also known as VP-16 and Etoposide phosphate, sold under the tradenames TOPOSAR, VEPESID, and ETOPOPHOS), and teniposide (also known as VM-26, sold under the tradename VUMON). 
     Examples of alkylating agents, include but are not limited to, 5-azacytidine (sold under the trade name VIDAZA), decitabine (sold under the trade name of DECOGEN), temozolomide (sold under the trade names TEMODAR and TEMODAL by Schering-Plough/Merck), dactinomycin (also known as actinomycin-D and sold under the tradename COSMEGEN), melphalan (also known as L-PAM, L-sarcolysin, and phenylalanine mustard, sold under the tradename ALKERAN), altretamine (also known as hexamethylmelamine (HMM), sold under the tradename HEXALEN), carmustine (sold under the tradename BCNU), bendamustine (sold under the tradename TREANDA), busulfan (sold under the tradenames B USULFEX ® and M YLERAN ®), carboplatin (sold under the tradename P ARAPLATIN ®), lomustine (also known as CCNU, sold under the tradename C EE NU®), cisplatin (also known as CDDP, sold under the tradenames P LATINOL ® and P LATINOL ®-AQ), chlorambucil (sold under the tradename L EUKERAN ®), cyclophosphamide (sold under the tradenames C YTOXAN ® and N EOSAR ®), dacarbazine (also known as DTIC, DIC and imidazole carboxamide, sold under the tradename DTIC-DOME®), altretamine (also known as hexamethylmelamine (HMM) sold under the tradename H EXALEN ®), ifosfamide (sold under the tradename I FEX ®), procarbazine (sold under the tradename M ATULANE ®), mechlorethamine (also known as nitrogen mustard, mustine and mechloroethamine hydrochloride, sold under the tradename M USTARGEN ®), streptozocin (sold under the tradename Z ANOSAR ®), thiotepa (also known as thiophosphoamide, TESPA and TSPA, and sold under the tradename T HIOPLEX®.    
     Examples of anti-tumor antibiotics include, but are not limited to, doxorubicin (sold under the tradenames A DRIAMYCIN ® and R UBEX ®), bleomycin (sold under the tradename L ENOXANE ®), daunorubicin (also known as dauorubicin hydrochloride, daunomycin, and rubidomycin hydrochloride, sold under the tradename C ERUBIDINE ®), daunorubicin liposomal (daunorubicin citrate liposome, sold under the tradename D AUNOXOME ®), mitoxantrone (also known as DHAD, sold under the tradename N OVANTRONE ®), epirubicin (sold under the tradename E LLENCE ™), idarubicin (sold under the tradenames I DAMYCIN ®, I DAMYCIN  PFS®), and mitomycin C (sold under the tradename M UTAMYCIN ®). 
     Examples of anti-metabolites include, but are not limited to, claribine (2-chlorodeoxyadenosine, sold under the tradename L EUSTATIN ®), 5-fluorouracil (sold under the tradename A DRUCIL ®), 6-thioguanine (sold under the tradename PURINETHOL®), pemetrexed (sold under the tradename A LIMTA ®), cytarabine (also known as arabinosylcytosine (Ara-C), sold under the tradename C YTOSAR -U®), cytarabine liposomal (also known as Liposomal Ara-C, sold under the tradename D EPO C YT ™), decitabine (sold under the tradename D ACOGEN ®), hydroxyurea (sold under the tradenames H YDREA ®, D ROXIA ™ and M YLOCEL ™), fludarabine (sold under the tradename F LUDARA ®), floxuridine (sold under the tradename FUDR®), cladribine (also known as 2-chlorodeoxyadenosine (2-CdA) sold under the tradename L EUSTATIN ™), methotrexate (also known as amethopterin, methotrexate sodium (MTX), sold under the tradenames R HEUMATREX ® and T REXALL ™), and pentostatin (sold under the tradename N IPENT ®). 
     Examples of retinoids include, but are not limited to, alitretinoin (sold under the tradename P ANRETIN ®), tretinoin (all-trans retinoic acid, also known as ATRA, sold under the tradename V ESANOID ®), Isotretinoin (13-c/s-retinoic acid, sold under the tradenames A CCUTANE ®, A MNESTEEM ®, C LARAVIS ®, C LARUS ®, D ECUTAN ®, I SOTANE® , I ZOTECH ®, O RATANE ®, I SOTRET ®, and S OTRET ®), and bexarotene (sold under the tradename T ARGRETIN ®). 
     Activity: STING Biochemical [3H]cGAMP Competition Assay 
     The individual compounds described in the Examples herein are defined as STING agonists by demonstrating binding to the STING protein with an EC 50  of 20 uM or less in the STING Biochemical [3H]cGAMP Competition Assay and demonstrating interferon production with a 20% or greater luminescence induction at 30 uM in the IFN-β secretion in the THP1 cell assay. 
     The ability of compounds to bind STING is quantified by the ability to compete with tritiated cGAMP ligand for human STING receptor membrane using a radioactive filter-binding assay. The binding assay employs STING receptor obtained from Hi-Five cell membranes overexpressing full-length HAQ STING prepared in-house and tritiated cGAMP ligand also purified in-house. 
     Abbreviations 
     
         
           1 H-NMR Proton nuclear magnetic resonance spectroscopy 
           19 F-NMR  19 F nuclear magnetic resonance spectroscopy 
           31 P-NMR  31 P nuclear magnetic resonance spectroscopy 
         Å Angstrom 
         A Bz  6-N-benzoyladenine 
         aq Aqueous 
         Ar Argon 
         ATP Adenosine 5′-triphosphate 
         Bz Benzoyl 
         CD 3 OD Deuterium-enriched methyl alcohol, deuterium-enriched methanol 
         CHCl 3  Trichloromethane 
         Ci Curie, a non-standard unit of radioactivity; 1Ci=3.7×10 10 Bq, where Bq is Becquerel, the SI unit of radioactivity, equivalent to 1 disintegration per second (dps) 
         CO 2  Carbon dioxide 
         d Doublet 
         d Day(s) 
         D 2 O Deuterium-enriched water 
         DCA Dichloroacetic acid 
         DCM, CH 2 Cl 2  Dichloromethane 
         ddd Doublet of doublet of doublet 
         ddt Doublet of doublet of triplet 
         DDTT (E)-N,N-dimethyl-N′-(3-thioxo-3H-1,2,4-dithiazol-5-yl)formimidamide 
         DMF N,N-dimethylformamide 
         DMOCP 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphineane 2-oxide 
         DMSO Dimethyl sulfoxide 
         DMTr 4,4′-dimethoxytrityl 
         DMTrCl 4,4′-dimethoxytrityl chloride 
         dq Doublet of quartet 
         EC 50  half maximal effective concentration, concentration of a drug, antibody or toxicant that induces a response halfway between the baseline and maximum after a specified exposure time 
         eq Equivalents 
         ES Electron spray 
         Et Ethyl 
         Et 2 O Diethyl ether 
         Et 3  SiH Triethylsilane 
         EtOAc Ethyl acetate 
         EtOH Ethyl alcohol, ethanol 
         g Gram 
         GTP Guanosine 5′-triphosphate 
         h Hour 
         H 2 O Water 
         HEPES 2-[4-(2-hydroxyethyl)piperazin 1-yl]ethanesulfonic acid, a zwitterionic organic chemical buffering agent 
         hept Heptet 
         Hex Hexanes 
         HF-Pyr Hydrogen fluoride-pyridine complex 
         HPLC High performance liquid chromatography 
         Hz Hertz 
         ITP Inosine 5′-triphosphate 
         J NMR Coupling constant 
         LCMS Liquid chromatography-mass spectroscopy 
         m Multiplet 
         M Molar, moles per liter 
         mCi Millicurie 
         Me Methyl 
         MeCN Acetonitrile 
         MeNH 2  Methylamine 
         mg Milligram 
         MgCl 2  Magnesium chloride 
         MHz Megahertz 
         min Minute(s) 
         mL, ml Milliliter 
         mM Millimole per liter 
         mmol Millimole 
         MOI Multiplicity of infection 
         MPLC Medium pressure liquid chromatography 
         MTBE Methyl t-butyl ether, methyl tertiary butyl ether 
         Na 2 SO 4  Sodium sulfate 
         NaCl Sodium chloride 
         NaHCO 3  Sodium bicarbonate 
         NaHSO 3  Sodium bisulfite 
         NaOH Sodium hydroxide 
         ng Nanogram(s) 
         NH 4 HCO 3  Ammonium bicarbonate 
         NH 4 OH Ammonium hydroxide 
         nL Nanoliter 
         nm Nanometer 
         nM Nanomolar 
         P 2 O 5  Phosphorus pentoxide 
         Py Pyridine 
         q Quartet 
         RPM, rpm Revolutions per minute 
         RT, rt Room temperature, approximately 25° C. 
         s Singlet 
         sat Saturated 
         t Triplet 
         TB S t-Butyldimethylsilyl 
         TMA Trimethylamine 
         TEA, Et 3 N Triethylamine 
         TFA Trifluoroacetic acid 
         TLC Thin layer chromatography 
         TMSCl Trimethylsilyl chloride 
         T R  Retention time 
         TrisCl Tris(hydroxymethyl)aminomethane hydrochloride 
         v/v Volume/volume 
         λ em  Emission wavelength 
         λ ex  Excitation wavelength 
         μg Microgram 
         μL, uL Microliter 
         μM, uM Micromolar 
       
    
     Preparation 1: N-(3-((2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)-methyl)-3-fluoro-4-hydroxytetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3R,4S,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((benzoyloxy)methyl)-4-fluorotetrahydrofuran-3-yl benzoate 
     
       
         
         
             
             
         
       
     
     To a mixture of 3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-amine (2.36 g, 17.4 mmol) in NMP (50 ml) was added NaH (60%, 0.744 g, 18.6 mmol). The mixture was vigorously stirred and after 1 h, generation of bubbles had completely ceased. The mixture was added to ((2R,3R,4S,5R)-3-(benzoyloxy)-5-bromo-4-fluorotetrahydrofuran-2-yl)methyl benzoate (neat, 5.25 g, 12.4 mmol) in one portion. The reaction was stirred for 18 h. LCMS showed several peaks with the desired mass (m/e=479). EtOAc (70 mL) and water (70 mL) were added to the reaction. Layers were separated, and the organic layer was washed with half saturated brine (3×10 mL) and brine (1×10 mL), dried (MgSO 4 ), and concentrated. The crude was purified via silica column eluting with 0 to 50% EtOAc in Hex to give the product. LCMS (ES, m/z): 479.3 [M+H] + .  1 H-NMR (500 MHz, DMSO-d 6 ): δ 8.62 (s, 1H), 8.34 (s, 1H), 8.28 (s, 1H), 8.10-8.04 (m, 2H), 7.97-7.90 (m, 2H), 7.77-7.69 (m, 1H), 7.67-7.55 (m, 3H), 7.49-7.42 (m, 2H), 6.97 (dd, J=6.5, 3.1 Hz, 1H), 6.49 (dt, J=17.6, 6.9 Hz, 1H), 6.16 (dt, J=56, 6.6 Hz, 1H), 4.76-4.62 (m, 3H). 
     Step 2. (2R,3R,4S,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-ol 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,4S,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((benzoyloxy)methyl)-4-fluorotetrahydrofuran-3-yl benzoate (2.00 g, 4.18 mmol) in pyridine (10 mL) at was added NH 3  in MeOH (7N, 20 mL, 140 mmol). It was stirred for 48 h. LCMS showed completion of the reaction (m/e=271). It was concentrated and purified by silica column chromatography eluting with 10% MeOH in CH 2 Cl 2  to give the desired product. LCMS (ES, m/z): 271.1 [M+H] + .  1 H-NMR (500 MHz, DMSO-d6): δ 8.54 (s, 1H), 8.33 (s, 1H), 8.22 (s, 1H), 6.73 (dd, J=6.5, 2.6 Hz, 1H), 6.00 (d, J=5.4 Hz, 1H), 5.51 (ddd, J=53, 7.2, 6.5 Hz, 1H), 4.93 (t, J=5.8 Hz, 1H), 4.86-4.74 (m, 1H), 3.91-3.83 (m, 1H), 3.77-3.61 (m, 2H). 
     Step 3: N-(3-((2R,3S,4R,5R)-3-fluoro-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,4S,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-ol (1.34 g, 4.96 mmol) in pyridine (30 mL) at 0° C. was added TMSCl (1.46 mL, 11.4 mmol). It was warmed to rt and stirred for 1 h. Then, it was recooled to 0° C. and BzCl (0.921 mL, 7.93 mmol) was added dropwise. The reaction was slowly warmed to rt over 2 h. LCMS showed completion of reaction (m/e=375, 479). Water (3 mL) was added. It was cooled to 0° C. and NH 3  in MeOH (7N, 2.8 mL, 20 mmol) was added. After 1 h, the reaction mixture was concentrated. It was purified by silica column chromatography eluting with 0 to 10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 375.2 [M+H] + .  1 H-NMR (500 MHz, DMSO-d 6 ): δ 11.95 (s, 1H), 8.98 (s, 1H), 8.10 (d, J=7.6 Hz, 2H), 7.73-7.66 (m, 1H), 7.59 (t, J=7.7 Hz, 2H), 6.91 (d, J=6.2 Hz, 1H), 6.06 (d, J=5.6 Hz, 1H), 5.59 (t, J=53, 6.8 Hz, 1H), 4.90 (t, J=5.8 Hz, 1H), 4.82 (dq, J=19.8, 7.0 Hz, 1H), 3.92 (td, J=7.6, 2.9 Hz, 1H), 3.75 (ddd, J=12.1, 5.6, 3.0 Hz, 1H), 3.66 (dt, J=12.0, 6.6 Hz, 1H). 
     Step 4: N-(3-((2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-fluoro-4-hydroxytetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(3-((2R,3S,4R,5R)-3-fluoro-4-hydroxy-5-(hydroxymethyl)-tetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide (1.25 g, 3.34 mmol) in pyridine (15 mL) at 0° C. was added DMTrCl (1.58 g, 4.68 mmol). It was stirred at rt for 1 h. LCMS showed a peak with the desired mass (m/e=677). It was partly concentrated (to 5 mL), and EtOAc (20 mL) and water (10 mL) were added. Layers were separated, and the aq layer was extracted with EtOAc (2×10 mL). The combined organics were washed with brine (5 mL), dried (MgSO 4 ), concentrated and purified by silica column chromatography eluting with 0 to 60% EtOAc in Hex to give the product. LCMS (ES, m/z): 675.5 [M−H] − .  1 H-NMR (500 MHz, DMSO-d 6 ): δ 8.13-8.07 (m, 2H), 7.69 (t, J=7.4 Hz, 1H), 7.59 (t, J=7.6 Hz, 2H), 7.35-7.29 (m, 2H), 7.23-7.10 (m, 6H), 6.97 (d, J=6.5 Hz, 1H), 6.81-6.74 (m, 2H), 6.74-6.67 (m, 2H), 6.07 (d, J=5.7 Hz, 1H), 5.62 (dt, J=53, 7.0 Hz, 1H), 4.91-4.79 (m, 1H), 4.15-4.07 (m, 1H), 3.69 (s, 3H), 3.67 (s, 3H), 3.44 (dd, J=10.4, 8.0 Hz, 1H), 3.21 (dd, J=10.3, 2.4 Hz, 1H). 
     Preparation 2: (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl (2-cyanoethyl)diisopropylphosphoramidite 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite 
     
       
         
         
             
             
         
       
     
     To a solution of 3-((bis(diisopropylamino)phosphino)oxy)propanenitrile (8.02 g, 26.6 mmol) in ACN (90 mL) at rt was added pyridin-1-ium 2,2,2-trifluoroacetate (3.85 g, 19.95 mmol) and a solution of N-(3-((2R,3 S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy) methyl)-3-fluoro-4-hydroxytetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide (9 g, 13.30 mmol) in ACN (90 mL). The resulting mixture was stirred for 1 h. Then, it was concentrated and the residue was dissolved in CH 2 Cl 2  (1000 mL). It was washed with aq NaHCO 3  (1%, 2×300 mL), water (300 mL) and brine (300 mL), dried (Na 2 SO 4 ), concentrated, and purified by reverse phase (C18) chromatography eluting with 0 to 95% ACN in water to give the product. LCMS (ES, m/z): 877.5 [M+H] + .  1 H-NMR: (400 MHz, DMSO-d 6 ): δ 12.01 (s, 1H), 8.92 (s, 1H), 8.11 (d, J=7.6 Hz, 2H), 7.66 (dt, J=42.3, 7.5 Hz, 3H), 7.32 (td J=7.2, 6.6, 2.9 Hz, 2H), 7.22-7.00 (m, 9H), 6.83-6.63 (m, 4H), 5.86 (ddt, J=52.8, 17.6, 6.9 Hz, 1H), 5.16 (td, J=17.7, 17.2, 8.8 Hz, 1H), 3.78-3.63 (m, 7H), 3.59-3.35 (m, 5H), 2.74 (t, J=5.9 Hz, 1H), 2.63 (t, J=5.9 Hz, 1H), 1.23-0.99 (m, 10H), 0.91 (d, J=6.7 Hz, 2H).  31 P-NMR: (162 MHz, DMSO-d 6 ): δ 150.26, 149.60 (2 s, 1P). 
     Preparation 3. N-(9-((2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: N-(9-((2R,3S,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a suspension of 2-amino-9-((2R,3 S,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-1,9-dihydro-6H-purin-6-one (Carbosynth catalog # ND10826, 1.50 g, 5.26 mmol) in pyridine (30 mL) at 0-5° C. was added TMSCl (2.86 g, 26.3 mmol), and the mixture was stirred at rt for 30 min. Then, isobutyric anhydride (2.50 g, 15.8 mmol) was added dropwise, and it was stirred for an additional for 2 h. Then, MeOH (5.3 mL) was added. After 5 min, NH 4 OH (10.5 mL) was added dropwise and stirring was continued for 30 min. The reaction mixture was concentrated under reduced pressure, and MeOH (2 mL) in CH 2 Cl 2  (18 mL) was added to the residue. Insolubles were filtered off, and the filtrate was concentrated and purified by flash column chromatography with 2-10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 356.1 [M+H] + .  1 H-NMR: (400 MHz, DMSO-d 6 ): δ 12.11 (s, 1H), 11.68 (s, 1H), 8.28 (s, 1H), 5.98 (d, J=6.1 Hz, 1H), 5.85 (d, J=8.0 Hz, 1H), 5.24 (t, J=5.4 Hz, 1H), 5.14 (d, J=4.1 Hz, 0.5H), 5.01 (d, J=4.2 Hz, 0.5H), 4.87-4.69 (m, 1H), 4.26 (t, J=4.4 Hz, 0.5H), 4.19 (t, J=4.4 Hz, 0.5H), 3.61 (t, J=4.9 Hz, 2H), 2.77 (hept, J=6.8 Hz, 1H), 1.13 (d, J=6.7 Hz, 6H).  19 F-NMR: (376 MHz, DMSO-d 6 ): δ −197.5 (s). 
     Step 2: N-(9-((2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     N-(9-((2R,3 S,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (1.30 g, 3.66 mmol) was co-evaporated with pyridine (3×10 mL) and re-dissolved in pyridine (26 mL). To the solution at 0-5° C. was added DMTrCl (1.36 g, 4.02 mmol). It was stirred at rt for 3 h and then, concentrated. CH 2 Cl 2  (40 mL, with 1% Et 3 N) was added, and it was washed with sat aq NaHCO 3  (15 mL), water (10 mL) and brine (10 mL). The organic solution was dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography using 0-10% MeOH in CH 2 Cl 2  (1% Et 3 N) to give the product. LCMS (ES, m/z): 656.2 [M−H] − .  1 H-NMR: (400 MHz, DMSO-d 6 ): δ 12.10 (s, 1H), 11.61 (s, 1H), 8.14 (s, 1H), 7.40-7.31 (m, 2H), 7.31-7.19 (m, 7H), 6.89-6.78 (m, 4H), 6.08 (d, J=6.1 Hz, 1H), 5.87 (d, J=7.3 Hz, 1H), 5.23 (dd, J=4.1, 1.8 Hz, 0H), 5.10 (d, J=4.4 Hz, 0H), 4.96 (dq, J=22.4, 5.9 Hz, 1H), 4.30 (dt, J=26.1, 4.6 Hz, 1H), 3.74 (d, J=1.1 Hz, 6H), 3.39 (dd, J=10.6, 5.7 Hz, 1H), 3.22 (dd, J=10.6, 3.8 Hz, 1H), 2.76 (p, J=6.8 Hz, 1H), 1.13 (d, J=6.8 Hz, 6H).  19 F-NMR: (376 MHz, DMSO-d 6 ): δ −198.1 (s, 1F). 
     The product of Preparation 3 may optionally be treated according to the procedures of Preparation 22, Steps 4 and 5 (below), to afford (2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate. LCMS (ES, m/z): 720 [M−H] − . 
     Preparation 4: N-(3-((2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: ((2R,3R,4S,5R)-5-(5-amino-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4-(benzoyloxy)-3-fluorotetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a suspension of 8-azaguanine (5.14 g, 33.8 mmol) in anhydrous CH 3 CN (100 mL) at rt was added dropwise (E)-trimethylsilyl N-(trimethylsilyl)acetimidate (16.53 mL, 67.6 mmol), then the mixture was stirred at 70° C. for 2 h. The reaction was cooled to rt, and a solution of ((2R,3R,4S)-5-acetoxy-4-(benzoyloxy)-3-fluorotetrahydrofuran-2-yl)methyl benzoate (6.8 g, 16.90 mmol) in anhydrous CH 3 CN (20 mL) was added followed by dropwise addition of tin(IV) chloride (67.6 mL, 67.6 mmol). The homogeneous solution was stirred at 70° C. for 2 h. The reaction was cooled to rt and concentrated. The residue was dissolved in EtOAc (1000 mL) and neutralized by pouring into sat aq NaHCO 3  (500 mL). The organic layer was separated, and the aq layer was extracted with EtOAc (4×500 mL). The organic layers were combined and washed with water (3×700 mL), brine, dried over anhydrous sodium sulfate, filtered, and concentrated to afford title compound without further purification. LCMS (ES, m/z): 495.3 [M+H] + . 
     Step 2: ((2R,3R,4S,5R)-4-(benzoyloxy)-3-fluoro-5-(5-isobutyramido-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)tetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,3R,4S,5R)-5-(5-amino-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4-(benzoyloxy)-3-fluorotetrahydrofuran-2-yl)methyl benzoate (8 g, 16.18 mmol) from Step 1 in anhydrous DMA (40 mL) at rt was added dropwise isobutyric anhydride (4.02 mL, 24.27 mmol). The mixture was stirred at 140° C. for 4 h. The reaction was cooled and diluted with EtOAc (600 mL), washed with sat aq NH 4 Cl (4×500 mL), brine, dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was purified by MPLC (220 g silica gel, eluting with a gradient of 100% hexanes to 100% ethyl acetate) to afford ((2R,3R,4S,5R)-4-(benzoyloxy)-3-fluoro-5-(5-isobutyramido-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)tetrahydrofuran-2-yl)methyl benzoate. LCMS (ES, m/z): 565.3 [M+H] + . 
     Step 3: N-(3-((2R,3S,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,3R,4S,5R)-4-(benzoyloxy)-3-fluoro-5-(5-isobutyramido-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)tetrahydrofuran-2-yl)methyl benzoate (6 g, 10.63 mmol) in THF (20 mL), CH 3 OH (16 mL), and water (4 mL) at 0° C. was added 5N aqueous NaOH (4.89 mL, 24.45 mmol) and stirred for 1 h. The reaction was neutralized with formic acid (1.223 mL, 31.9 mmol). The solvent was removed, and the residue was purified by MPLC (120 g, silica gel, eluting with a gradient of 100% CH 2 Cl 2  to 20% CH 3 OH/CH 2 Cl 2 ) to afford N-(3-((2R,3 S,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide. LCMS (ES, m/z): 357.2 [M+H] + . 
     Step 4: N-(3-((2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(3-((2R,3S,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide (3 g, 8.42 mmol) in anhydrous pyridine (40 mL) at 0° C. was added 4,4′-dimethoxytrityl chloride (3.42 g, 10.10 mmol). The ice bath was removed, and the reaction mixture was allowed to reach RT and was stirred for 2 h. The mixture was diluted with EtOAc (400 mL), washed with sat aq NaHCO 3  (100 mL), water (3×100 mL), brine, and dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was purified by MPLC (120 g silica gel, eluting with a gradient of 100% CH 2 Cl 2  to 15% CH 3 OH/CH 2 CH 2  to afford N-(3-((2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide. LCMS (ES, m/z): 659.3 [M+H] + . 
     Preparation 5: N-(3-((2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     N-(3-((2R,3 S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide was prepared according to procedures analogous to those described for Preparation 4 using the appropriately substituted ribose in Step 1. LCMS (ES, m/z): 659.4 [M+H] + . 
     Preparation 6: N-(3-((2R,3R,5S)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-hydroxytetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl) isobutyramide 
     
       
         
         
             
             
         
       
     
     N-(3-((2R,3R,5 S)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-hydroxytetrahydrofuran-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide was prepared according to procedures analogous to those described for Preparation 4 using the appropriately substituted ribose in Step 1. LCMS (ES, m/z): 641.2 [M+H] + . 
     Preparation 7: 3-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-2-deoxy-2-fluoro-β-D-arabinofuranosyl}-N-(phenylcarbonyl)-3H-imidazo[4,5-b]pyridin-7-amine 
     
       
         
         
             
             
         
       
     
     Step 1: 3-[2-deoxy-2-fluoro-3,5-bis-O-(phenylcarbonyl)-β-D-arabinofuranosyl]-7-nitro-3H-imidazo[4,5-b]pyridine 
     
       
         
         
             
             
         
       
     
     To a stirred mixture of freshly ground KOH (308 mg, 5.48 mmol) in acetonitrile (50 mL) was added tris(2-(2-methoxyethoxy)ethyl)amine (0.070 mL, 0.219 mmol). The reaction mixture was aged for 15 min at ambient temperature followed by addition of 7-nitro-3H-imidazo[4,5-b]pyridine (600 mg, 3.66 mmol) in a single portion. The resulting mixture was stirred at ambient temperature for 15 min. A solution of 2-deoxy-2-fluoro-3,5-bis-O-(phenylcarbonyl)-α-D-arabinofuranosyl bromide (1700 mg, 4.02 mmol) in acetonitrile (10 mL) was added dropwise and the resulting mixture was vigorously stirred at RT for 17 h. The reaction mixture was diluted with sat aq ammonium chloride (80 mL) and extracted with DCM (3×150 mL). The organic extracts were combined, dried over sodium sulphate and concentrated under reduced pressure. The resulting residue was purified by column chromatography on silica gel; 120 g prepacked, (0-70% ethyl acetate/hexanes) to afford 3-[2-deoxy-2-fluoro-3,5-bis-O-(phenylcarbonyl)-3-D-arabinofuranosyl]-7-nitro-3H-imidazo[4,5-b]pyridine. MS: 507 (M+H) + . 
     Step 2: 3-[2-deoxy-2-fluoro-3,5-bis-O-(phenylcarbonyl)-β-D-arabinofuranosyl]-3H-imidazo[4,5-b]pyridin-7-amine 
     
       
         
         
             
             
         
       
     
     To a stirred solution of 3-[2-deoxy-2-fluoro-3,5-bis-O-(phenylcarbonyl)-β-D-arabinofuranosyl]-7-nitro-3H-imidazo[4,5-b]pyridine (1380 mg, 2.72 mmol) in methanol (55 mL) at RT was added platinum(IV) oxide (61.9 mg, 0.272 mmol). The reaction mixture was placed under an atmosphere of hydrogen and stirred at RT for 72 h. The catalyst was removed by filtration through a plug of CELITE. The filtrate was concentrated under reduced pressure, and the resulting residue was purified by column chromatography on silica gel; 80 g prepacked, ((0-40% (3:1, ethyl acetate:ethanol)/hexanes) to afford 3-[2-deoxy-2-fluoro-3,5-bis-O-(phenylcarbonyl)-β-D-arabinofuranosyl]-3H-imidazo[4,5-b]pyridin-7-amine. MS: 477 (M+H) + . 
     Step 3: 3-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-3H-imidazo[4,5-b]pyridin-7-amine 
     
       
         
         
             
             
         
       
     
     To a stirred solution of 3-[2-deoxy-2-fluoro-3,5-bis-O-(phenylcarbonyl)-β-D-arabinofuranosyl]-3H-imidazo[4,5-b]pyridin-7-amine (995 mg, 2.09 mmol) in methanol (36 mL) at ambient temperature was added ammonia (7N in methanol, 12 mL, 84.0 mmol). The resulting solution was brought to 80° C. and stirred for 5 h. The reaction mixture was cooled to RT and concentrated under reduced pressure. The resulting residue was suspended in methanol/dichloromethane and sonicated until a solid precipitated out of solution. Solid was collected by filtering through a glass frit affording 3-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-3H-imidazo[4,5-b]pyridin-7-amine. MS: 269 (M+H) + . 
     Step 4: 3-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-N-(phenylcarbonyl)-3H-imidazo[4,5-b]pyridin-7-amine 
     
       
         
         
             
             
         
       
     
     To a stirred solution of 3-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-3H-imidazo[4,5-b]pyridin-7-amine (550 mg, 2.05 mmol) in pyridine (6.5 mL) at RT was added TMSCl (2.62 mL, 20.5 mmol). The resulting solution was stirred for 1.5 h followed by addition of benzyol chloride (0.357 mL, 3.08 mmol). After stirring for an additional hour, water (2.15 mL) was added to the reaction mixture, which was then stirred for 45 min. The reaction mixture was cooled to 0° C. and aqueous ammonia (28% w/w) (0.370 mL, 4.79 mmol) was added. The reaction mixture was returned to RT and stirred for 45 min and then concentrated under reduced pressure. The resulting residue was taken up in water (20 mL) and extracted with ethyl acetate (3×40 mL). The organic extracts were combined washed with brine, dried over sodium sulphate and concentrated under reduced pressure. The resulting residue was purified by column chromatography on silica gel; 120 g prepacked, (0-7% methanol/dichloromethane) to afford 3-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-N-(phenylcarbonyl)-3H-imidazo[4,5-b]pyridin-7-amine. MS: 373 (M+H) + . 
     Step 5: 3-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-2-deoxy-2-fluoro-β-D-arabinofuranosyl}-N-(phenylcarbonyl)-3H-imidazo[4,5-b]pyridin-7-amine 
     
       
         
         
             
             
         
       
     
     To a stirred mixture of 3-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-N-(phenylcarbonyl)-3H-imidazo[4,5-b]pyridin-7-amine (185 mg, 0.497 mmol) and 4 Å molecular sieves in pyridine (3 mL) at 0° C. was added 4,4′-dimethoxytrityl chloride (253 mg, 0.745 mmol) in a single portion. The reaction mixture was allowed to warm to RT and was stirred for 18 h. Sieves were removed by filtration and the filtrate was concentrated under reduced pressure. The resulting residue was taken up in a mixture of methanol/ether and added to water. The phases were separated, and the aqueous layer was extracted with ether (3 times). The organic extracts were combined, washed with brine, dried over sodium sulphate and concentrated under reduced pressure. The resulting residue was purified by column chromatography on silica gel; 40 g prepacked, ((0-40% (3:1, ethyl acetate:ethanol)/hexanes) to afford 3-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-2-deoxy-2-fluoro-β-D-arabinofuranosyl}-N-(phenylcarbonyl)-3H-imidazo[4,5-b]pyridin-7-amine. MS: 675 (M+H) + . 
     Preparation 8: 1-((2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-1,5-dihydro-4H-imidazo[4,5-c]pyridin-4-one 
     
       
         
         
             
             
         
       
     
     Step 1: ((2R,3S,4S)-4-acetoxy-3-fluoro-5-(4-oxo-4,5-dihydro-1H-imidazo[4,5-c]pyridin-1-yl)tetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a suspension of 4-(benzyloxy)-1H-imidazo[4,5-c]pyridine (0.795 g, 3.53 mmol) and (3S,4S,5R)-5-((benzoyloxy)methyl)-4-fluorotetrahydrofuran-2,3-diyl diacetate (1 g, 2.94 mmol) in ACN (20 mL) and CH 2 Cl 2  (10 mL) at 0° C. under Ar was added 2,3,4,6,7,8,9,10-octahydropyrimido[1,2-a]azepine (1.34 g, 8.815 mmol). The resulting mixture was stirred at 0° C. for 30 min. Then, trimethylsilyl trifluoromethanesulfonate (3.92 g, 17.65 mmol) was added to the solution, and it was stirred at 0° C. for 30 min. Then, it was heated to 80° C. for 16 h. The reaction was cooled to rt and sat aq NaHCO 3  (10 mL) and water (30 mL) were added. It was extracted with EtOAc (3×50 mL). The combined organic layers was washed with brine, dried over (Na 2 SO 4 ), concentrated, and the residue was purified by silica gel column chromatography, eluted with 1 to 10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 416.3 [M+H] + . 
     Step 2: 1-((2R,3S,4R,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-1,5-dihydro-4H-imidazo[4,5-c]pyridin-4-one 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,3S,4S)-4-acetoxy-3-fluoro-5-(4-oxo-4,5-dihydro-1H-imidazo[4,5-c]pyridin-1-yl)tetrahydrofuran-2-yl)methyl benzoate (2.5 g, 5.3 mmol) in MeOH (10 mL) was added sodium methanolate (3.47 g, 21.2 mmol). The solution was stirred at rt for 1 h. It was neutralized with AcOH, and the solution was concentrated. The residue was purified by reverse phase (AQ C18) chromatography eluted with 0 to 30% ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 270.0 [M+H] + .  1 H NMR (400 MHz, DMSO-d 6 ) δ 11.31 (s, 1H), 8.06 (s, 1H), 7.23 (d, J=7.1 Hz, 1H), 6.62 (d, J=7.1 Hz, 1H), 6.37 (d, J=2.9 Hz, 1H), 5.85 (d, J=2.8 Hz, 1H), 5.22-4.98 (m, 2H), 4.54 (d, J=17.7 Hz, 1H), 4.28 (dtd, J=29.6, 6.0, 3.1 Hz, 1H), 3.93-3.62 (m, 2H). 
     Step 3: 1-((2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-1,5-dihydro-4H-imidazo[4,5-c]pyridin-4-one 
     
       
         
         
             
             
         
       
     
     To a stirred solution of 1-((2R,3S,4R,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl)-1H-imidazo[4,5-c]pyridin-4(5H)-one (340 mg, 1.26 mmol) in pyridine (3 mL) at rt was added 4,4′-(chloro(phenyl)methylene)bis(methoxybenzene) (426 mg, 1.1 mmol). 
     It was stirred for 4 h. The mixture was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography eluted with 1 to 10% MeOH in CH 2 Cl 2  (0.5% Et 3 N) to give the product. LCMS (ES, m/z): 572.3 [M+H] + .  1 H NMR (400 MHz, DMSO-d 6 ) δ 11.32 (d, J=5.9 Hz, 1H), 7.95 (s, 1H), 7.41 (d, J=7.8 Hz, 2H), 7.37-7.15 (m, 8H), 6.86 (dd, J=10.5, 8.6 Hz, 4H), 6.60 (d, J=7.1 Hz, 1H), 6.50-6.36 (m, 1H), 5.92 (d, J=2.6 Hz, 1H), 5.77 (s, 1H), 5.27-5.06 (m, 1H), 4.65-4.42 (m, 2H), 3.73 (d, J=2.6 Hz, 6H), 3.30-3.24 (m, 1H). 
     Preparation 9: N-(7-((2R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-hydroxytetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     Step 1: (3R,4R,5R)-2-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)tetrahydrofuran-2-ol 
     
       
         
         
             
             
         
       
     
     To a stirring mixture of 7-bromoimidazo[2,1-f][1,2,4]triazin-4-amine (41 g, 0.19 mol) in THF (0.50 L) at 0° C. was added MeMgBr (3.0M in THF, 66 mL, 0.19 mol) dropwise to maintain the internal temperature below 10° C. Bis(chlorodimethylsilyl)ethane (41 g, 190 mmol) was added in one portion. MeMgBr (3.0M in diethyl ether, 66 mL, 0.19 mol) was then added dropwise to maintain the internal temperature below 10° C. i-PrMgCl—LiCl (1.3 M in THF, 0.16 L, 0.21 mol) was added while maintaining the internal temperature below 10° C. A mixture of (3R,4R,5R)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)dihydrofuran-2(3H)-one (160 g, 0.38 mol) in THF was added dropwise at 0° C., and the mixture was then allowed to warm to rt and was stirred for 12 h. The mixture was diluted with saturated aqueous ammonium chloride (100 mL) and extracted with ethyl acetate (3×1000 mL). The combined organic layers were dried over sodium sulfate and concentrated under reduced pressure. The resulting residue was purified by column chromatography (column height: 2500 mm, diameter: 1000 mm, 25% to 75% ethyl acetate gradient in hexanes) to afford (3R,4R,5R)-2-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)-tetrahydrofuran-2-ol. 
     Step 2: 7-((3S,4R,5R)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)tetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-amine 
     
       
         
         
             
             
         
       
     
     To a stirring mixture of (3R,4R,5R)-2-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)tetrahydrofuran-2-ol (64 g, 0.12 mmol) in DCM (1.3 L) at 0° C. was added triethylsilane (81 g, 0.69 mol), and then boron trifluoride diethyl etherate (21 g, 0.15 mol). The mixture was then allowed to warm to 25° C., and the mixture was stirred for 1 h. More boron trifluoride diethyl etherate (57 g, 0.40 mol) was added, and the mixture was then heated to 35° C. for 4 h. Upon cooling to rt, the mixture was quenched with saturated aqueous sodium bicarbonate (200 mL) and then extracted with ethyl acetate (3×300 mL). The combined organic layers were dried over sodium sulfate and concentrated under reduced pressure. The resulting residue was purified by column chromatography (15-75% ethyl acetate gradient in hexanes) to afford 7-((3S,4R,5R)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)tetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-amine. MS (ES, m/z)=538 [M+H]+. 
     Step 3: (3R,4S,5R)-2-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-5-(hydroxymethyl)-tetrahydrofuran-3,4-diol 
     
       
         
         
             
             
         
       
     
     To a stirring mixture of 7-((3S,4R,5R)-3,4-bis(benzyloxy)-5-((benzyloxy)methyl)-tetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-amine (12 g, 22 mmol) in DCM (850 mL) at −78° C. was added boron trichloride (18 g, 0.16 mol) dropwise. Upon completion, the mixture was stirred at −78° C. for 3 h. After 3 h, the mixture was quenched with methanol (50 mL) at −78° C., and the mixture was allowed to warm to 25° C. The mixture was concentrated under reduced pressure. The residue was purified by column chromatography (9-25% methanol gradient in dichloromethane) to afford (3R,4S,5R)-2-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol. 
     Step 4. (6aR,8S,9S,9aS)-8-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-9-ol 
     
       
         
         
             
             
         
       
     
     To a stirred mixture of (2S,3R,4S,5R)-2-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol (4.0 g, 15 mmol) in pyridine (0.10 L) was added 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (5.8 mL, 18 mmol). After 3 h, the mixture was diluted with toluene (50 mL) and then concentrated. The resulting mixture was taken up in DCM and methanol and then silica gel (40 g) was added. The mixture was concentrated, placed under vacuum for 1 h and then purified by column chromatography (0-80% ethyl acetate gradient in hexanes) to afford (6aR,8S,9S,9aS)-8-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-9-ol. MS (ES, m/z)=510 [M+H]+. 
     Step 5: O-((6aR,8S,9S,9aR)-8-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-9-yl) 1H-imidazole-1-carbothioate 
     
       
         
         
             
             
         
       
     
     To a mixture of (6aR,8S,9S,9aS)-8-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-9-ol (6.45 g, 12.7 mmol) in acetonitrile (63.0 mL) and pyridine (63.0 mL) was added 1,1′-thiocarbonyldiimidazole (2.71 g, 15.2 mmol). After 90 min, more 1,1′-thiocarbonyldiimidazole (2.71 g, 15.2 mmol) was added, and the mixture was stirred overnight. After stirring overnight, the mixture was concentrated and purified by column chromatography (0-100% ethyl acetate gradient in hexanes) to afford O-((6aR,8S,9S,9aR)-8-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-9-yl) 1H-imidazole-1-carbothioate. MS (ES, m/z)=620 [M+H]+. 
     Step 6: 7-((6aR,8R,9aS)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-8-yl)imidazo[2,1-f][1,2,4]triazin-4-amine 
     
       
         
         
             
             
         
       
     
     To a mixture of O-((6aR,8S,9S,9aR)-8-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-9-yl) (5.65 g, 9.11 mmol) in toluene (91.0 mL) was added 2,2′-azobis(2-methylpropionitrile (0.300 g, 1.82 mmol) and tris(trimethylsilyl)silane (4.22 mL, 13.7 mmol). The mixture was heated to 85° C. for 30 min. After 30 min, the mixture was allowed to cool to rt and placed directly on the column and purified (0-80% ethyl acetate gradient in hexanes) to afford 7-((6aR,8R,9aS)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-8-yl)imidazo[2,1-f][1,2,4]triazin-4-amine. MS (ES, m/z)=494 [M+H]+ 494. 
     Step 7: N-benzoyl-N-(7-((6aR,8R,9aS)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-8-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a mixture of 7-((6aR,8R,9aS)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-8-yl)imidazo[2,1-f][1,2,4]triazin-4-amine (15.7 g, 31.8 mmol) in pyridine (64.0 mL) was added benzoyl chloride (11.0 mL, 95.0 mmol), and the mixture was heated to 50° C. for 45 min. After 45 min, the mixture was allowed to cool to rt. After cooling, a precipitate formed and was filtered off. The filtrate was diluted with DCM (50 mL) and toluene (50 mL). The mixture was concentrated to about 50 mL. The mixture was filtered, and the solids washed with DCM. The filtrate and washes were combined, loaded onto a column, and purified (0-50% ethyl acetate gradient in hexanes) to afford N-benzoyl-N-(7-((6aR,8R,9aS)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-8-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide. MS (ES, m/z)=702 [M+H]+. 
     Step 8: N-(7-((2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a mixture of N-benzoyl-N-(7-((6aR,8R,9aS)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-8-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide (10 g, 14 mmol) in tetrahydrofuran (0.14 L) was added TBAF ((1.0M in THF, 29 mL, 29 mmol), and the mixture was stirred for 1 h. After 1 h, the mixture was concentrated and purified by column chromatography to afford N-(7-((2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)tetrahydro-furan-2-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide. MS (ES, m/z)=356 [M+H]+. 
     Step 9: N-(7-((2R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-hydroxytetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a mixture of N-(7-((2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide (6.1 g, 17 mmol) in pyridine (86 mL) at 0° C. was added 4,4′-(chloro(phenyl)methylene)bis(methoxybenzene) (5.8 g, 17 mmol), and the mixture was allowed to warm to RT overnight. After stirring overnight, the mixture was diluted with toluene and then concentrated under reduced pressure to afford the crude product. The crude product was purified by silica gel chromatography (0-100% ethyl acetate gradient in hexanes) to afford N-(7-((2R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-4-hydroxytetrahydrofuran-2-yl)imidazo[2,1-f][1,2,4]triazin-4-yl)benzamide. MS (ES, m/z)=658 [M+H]+. 
     Preparation 10: (2R,3R,4S,5R)-2-(4-amino-1H-[1,2,3]triazolo[4,5-c]pyridin-1-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3R,4R,5R)-2-(acetoxymethyl)-5-(4-chloro-1H-[1,2,3]triazolo[4,5-c]pyridin-1-yl)tetrahydrofuran-3,4-diyl diacetate 
     
       
         
         
             
             
         
       
     
     To a suspension of 4-chloro-1H-[1,2,3]triazolo[4,5-c]pyridine (1.0 g, 6.5 mmol) and (3R,4R,5R)-5-(acetoxymethyl)tetrahydrofuran-2,3,4-triyl triacetate (3.1 g, 9.7 mmol) in nitromethane (50 mL) was added BF 3 .Et 2 O (1.23 mL, 9.7 mmol), and the resulting mixture was heated at 50° C. for 2 h. The reaction mixture was cooled to rt, diluted with 100 mL of DCM and washed with sat aq. NaHCO 3  (100 mL) and brine (100 mL). The separated organic layer was dried over Na 2 SO 4  and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-100% EtOAc:EtOH (3:1)/Hexane. LCMS (ES, m/z): 413.07 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 8.40 (d, J=5.8 Hz, 1H), 7.56 (d, J=5.8 Hz, 1H), 6.43 (d, J=4.1 Hz, 1H), 6.17 (dd, J=5.3, 4.1 Hz, 1H), 5.74 (t, J=5.3 Hz, 1H), 5.32 (s, 1H), 4.58 (ddd, J=5.3, 3.9, 2.9 Hz, 1H), 4.42 (dd, J=12.5, 3.0 Hz, 1H), 4.25 (dd, J=12.5, 3.9 Hz, 1H), 2.17 (d, J=18.8 Hz, 6H), 2.03 (s, 3H). 
     Step 2: (2R,3R,4S,5R)-2-(4-amino-1H-[1,2,3]triazolo[4,5-c]pyridin-1-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,4R,5R)-2-(acetoxymethyl)-5-(4-chloro-1H-[1,2,3]triazolo[4,5-c]pyridin-1-yl)tetrahydrofuran-3,4-diyl diacetate (1.2 g, 2.9 mmol) in MeOH (8.3 mL) was added a 7N solution of ammonia in MeOH (8.3 mmol, 58.1 mmol). The reaction mixture was stirred at 150° C. in a sealed Q-Tube™ Pressure Tube Reactor for 18 h. Excess solvent was removed under reduced pressure, and the residue was purified by a reverse phase silica gel column, eluting with 0-10% Acetonitrile/H 2 O containing 0.05% TFA. LCMS (ES, m/z): 268.17 [M+H] + .  1 H NMR (500 MHz, DMSO-d 6 ) δ 13.87 (s, 2H), 9.34 (s, 4H), 7.89 (d, J=7.1 Hz, 2H), 7.51 (d, J=7.0 Hz, 2H), 7.42 (s, 4H), 7.32 (s, 6H), 7.22 (s, 5H), 6.69 (s, 2H), 6.30 (d, J=4.9 Hz, 2H), 5.72 (s, 2H), 5.41 (s, 2H), 4.75-4.67 (m, 0H), 4.65 (t, J=5.0 Hz, 2H), 4.27 (t, J=4.6 Hz, 2H), 4.07 (q, J=4.2 Hz, 2H), 3.86-3.67 (m, 2H), 3.69-3.58 (m, 2H), 3.54 (dd, J=12.0, 4.7 Hz, 2H), 3.48-3.38 (m, 1H), 3.28 (s, 1H), 3.23 (s, 0H), 1.76 (d, J=0.5 Hz, 5H), 1.11 (dt, J=26.0, 7.1 Hz, 1H). 
     Preparation 11: 9-{3-azido-5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-3-deoxy-β-D-ribofuranosyl}-2-[(2-methylpropanoyl)amino]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Nucleosides, Nucleotides  &amp;  Nucleic Acids  2005, 24(10-12), 1707-1727). 
     Preparation 12: 9-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-3-deoxy-3-fluoro-β-D-xylofuranosyl}-2-[(2-methylpropanoyl)amino]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Tetrahedron Letters,  1989, 30(24), 3171-3174). 
     Preparation 13: 1-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-3-deoxy-3-fluoro-β-D-ribofuranosyl}-6-[(2-methylpropanoyl)amino]-1,5-dihydro-4H-imidazo[4,5-c]pyridin-4-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures (WO2002057425). 
     Preparation 14: N-(3-((2R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3,3-difluoro-4-hydroxytetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide 
     
       
         
         
             
             
         
       
     
     Step 1: (((2R,3R)-3-(benzoyloxy)-5-((diphenoxyphosphoryl)oxy)-4,4-difluorotetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To ((2R,3R)-3-(benzoyloxy)-4,4-difluoro-5-hydroxytetrahydrofuran-2-yl)methyl benzoate (20.0 g, 52.9 mmol) in toluene (150 mL) at 0° C. were added Et 3 N (7.74 mL, 55.5 mmol) and diphenyl phosphoryl chloride (12.1 mL, 58.2 mmol) in toluene (20 mL) dropwise. The reaction was warmed to rt and stirred for 3 h. LCMS showed completion of the reaction (m/e=611). Water (30 mL) and aq HCl (1 M, 5 mL) were added. Layers were separated, and the aq layer was extracted with CH 2 Cl 2  (2×30 mL). The combined organic solution was washed with sat aq NaHCO 3  (20 mL), and Brine (20 mL), dried (MgSO 4 ), and concentrated. It was purified by silica column chromatography eluting with 0 to 30% EtOAc in Hex to give the product. LCMS (ES, m/z): 611.3 [M+H] + . 
     Step 2: ((2R,3R,5R)-3-(benzoyloxy)-5-bromo-4,4-difluorotetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To ((2R,3R)-3-(benzoyloxy)-5-((diphenoxyphosphoryl)oxy)-4,4-difluorotetrahydrofuran-2-yl)methyl benzoate (23.8 g, 39.0 mmol) at 0° C. was added HBr in acetic acid (33%, 51.2 mL, 292 mmol). It was stirred as it warmed to rt. After 6 h, LCMS showed completion of the reaction (m/e=441 and 443). CH 2 Cl 2  (200 mL) was added, and the organic layer was washed with water (2×50 mL), sat aq NaHCO 3  (2×50 mL) and brine (50 mL). It was dried (MgSO 4 ) and concentrated to give the crude product. It was used in the next step without purification. LCMS (ES, m/z): 441.1, 443.1 [M+H] + . 
     Step 3: (2R,3R,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((benzoyloxy)methyl)-4,4-difluorotetrahydrofuran-3-yl benzoate 
     
       
         
         
             
             
         
       
     
     To a mixture of 3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-amine (3.21 g, 23.6 mmol) in NMP (60 mL) was added NaH (60%, 0.979 g, 24.5 mmol). The mixture was vigorously stirred, and after 1 h, generation of bubbles had completely ceased. To the mixture was added to ((2R,3R,5R)-3-(benzoyloxy)-5-bromo-4,4-difluorotetrahydrofuran-2-yl)methyl benzoate (neat, 8.00 g, 18.1 mmol). The mixture was stirred vigorously for 30 min. Then, it was heated to 90° C. for 5 h. It was cooled to rt, and CH 2 Cl 2  (300 mL) and water (150 mL) were added. The phases were separated, and the organic layer was washed with water (8×150 mL) and brine (50 mL), dried (MgSO 4 ) and concentrated. The residue was purified by silica column chromatography eluting with 0% to 30% EtOAc to give the desired product. LCMS (ES, m/z): 497.1 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 8.44 (s, 1H), 8.15-8.08 (m, 2H), 8.08-7.99 (m, 2H), 7.63 (ddt, J=8.7, 7.1, 1.3 Hz, 1H), 7.56-7.44 (m, 3H), 7.40-7.32 (m, 2H), 6.79-6.68 (m, 2H), 6.04 (bs, 2H), 4.92-4.84 (m, 1H), 4.80-4.72 (m, 2H). 
     Step 4. (2R,3R,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4,4-difluoro-2-(hydroxymethyl)tetrahydrofuran-3-ol 
     
       
         
         
             
             
         
       
     
     To (2R,3R,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((benzoyloxy) methyl)-4,4-difluorotetrahydrofuran-3-yl benzoate (1.05 g, 2.11 mmol) was added ammonia in MeOH (7N, 9.0 mL, 63 mmol), and the mixture was stirred for 24 h. LCMS showed completion of reaction (m/e=289). It was concentrated and purified by silica column chromatography eluting with 0 to 15% MeOH in CH 2 Cl 2  to give the desired product. LCMS (ES, m/z): 289.1 [M+H] + .  1 H-NMR (500 MHz, DMSO-d 6 ): δ 8.65 (s, 1H), 8.36 (s, 1H), 8.32 (s, 1H), 6.65 (d, J=12.4 Hz, 1H), 6.40 (d, J=6.7 Hz, 1H), 5.03 (dd, J=6.4, 5.3 Hz, 1H), 4.83 (dq, J=16.5, 8.9 Hz, 1H), 4.00 (t, J=6.7 Hz, 1H), 3.77 (ddd, J=12.3, 5.2, 2.5 Hz, 1H), 3.68 (dt, J=12.5, 6.3 Hz, 1H). 
     Step 5. N-(3-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,5R)-5-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4,4-difluoro-2-(hydroxymethyl)tetrahydrofuran-3-ol (0.57 g, 2.0 mmol) in pyridine (15 mL) at 0° C. was added TMSCl (0.55 mL, 4.3 mmol). It was warmed to rt and stirred for 1 h. Then, it was recooled to 0° C. and BzCl (0.34 mL, 2.9 mmol) was added dropwise. The reaction was slowly warmed rt over 2 h. LCMS showed completion of reaction (m/e=393, 497). It was cooled to 0° C., and ammonium hydroxide (28%, 1.1 mL, 7.9 mmol) was added. After 30 min, it was concentrated and purified by silica column chromatography eluting with 0 to 10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 393.3 [M+H] + .  1 H-NMR (500 MHz, DMSO-d 6 ): δ 12.02 (s, 1H), 9.01 (s, 1H), 8.13-8.07 (m, 2H), 7.73-7.66 (m, 1H), 7.64-7.55 (m, 2H), 6.86 (d, J=11.6 Hz, 1H), 6.46 (d, J=6.7 Hz, 1H), 5.01 (dd, J=6.3, 5.4 Hz, 1H), 4.86 (dt, J=16.7, 8.3 Hz, 1H), 4.04 (ddd, J=8.8, 6.2, 2.6 Hz, 1H), 3.78 (ddd, J=12.3, 5.4, 2.7 Hz, 1H), 3.68 (dt, J=12.4, 6.2 Hz, 1H). 
     Step 6. N-(3-((2R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3,3-difluoro-4-hydroxytetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(3-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)-tetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide (0.68 g, 1.7 mmol) in pyridine (15 mL) at 0° C. was added DMTrCl (0.65 g, 1.9 mmol). It was stirred at rt for 1 h. LCMS showed a peak with the desired mass (m/e=695). It was partly concentrated (to 5 mL), and EtOAc (20 mL) and water (10 mL) were added. The phases were separated, and the aqueous layer was extracted with EtOAc (2×10 mL). The combined organic portions were washed with brine, dried (MgSO 4 ), concentrated and purified by silica column chromatography eluting with 0% to 60% EtOAc in Hex to give the product. LCMS (ES, m/z): 695.2 [M+H] + .  1 H-NMR (500 MHz, DMSO-d 6 ): δ 12.05 (s, 1H), 8.93 (s, 1H), 8.11 (d, J=7.6 Hz, 2H), 7.70 (m, 1H), 7.60 (t, J=7.7 Hz, 2H), 7.38-7.32 (m, 2H), 7.25-7.13 (m, 7H), 6.96 (d, J=11.9 Hz, 1H), 6.84-6.73 (m, 4H), 6.48 (d, J=6.9 Hz, 1H), 4.97 (dq, J=16.7, 8.3 Hz, 1H), 4.23 (m, 1H), 3.70 (s, 3H), 3.69 (s, 3H), 3.42-3.36 (m, 1H), 3.32-3.28 (m, 1H). 
     Preparation 15: N-(7-((2R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3,3-difluoro-4-hydroxytetrahydrofuran-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     Step 1. ((2R,3R,5R)-3-(benzoyloxy)-5-(4-chloro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-4,4-difluorotetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a solution of 4-chloro-7H-pyrrolo[2,3-d]pyrimidine (4.06 g, 26.4 mmol) and ((2R,3R)-3-(benzoyloxy)-4,4-difluoro-5-hydroxytetrahydrofuran-2-yl)methyl benzoate (10.0 g, 26.4 mmol) and triphenylphosphine (20.80 g, 79 mmol) in THF (100 mL) was added (E)-diazene-1,2-diylbis(piperidin-1-ylmethanone) (20.01 g, 79 mmol) dropwise. It was slowly warmed to rt. After stirring for 2 h, the mixture was concentrated. The residue was purified by silica gel column chromatography using 0-20% EtOAc in Petroleum Ether to give the product. LCMS (ES, m/z): 514.3 [M+H] + .  1 H-NMR (300 MHz, DMSO-d 6 ): δ 8.71 (s, 1H), 8.08-7.87 (m, 5H), 7.76-7.42 (m, 6H), 6.98 (dd, J=10.3, 7.9 Hz, 1H), 6.84 (d, J=3.8 Hz, 1H), 6.29 (ddd, J=10.0, 6.0, 3.8 Hz, 1H), 5.44 (q, J=5.5 Hz, 1H), 4.79-4.60 (m, 2H). 
     Step 2. (2R,3R,5R)-5-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-4,4-difluoro-2-(hydroxymethyl)tetrahydrofuran-3-ol 
     
       
         
         
             
             
         
       
     
     A solution of ((2R,3R,5R)-3-(benzoyloxy)-5-(4-chloro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-4,4-difluorotetrahydrofuran-2-yl)methyl benzoate (1.9 g, 3.70 mmol) in NH 3 /2-propanol (saturated at −78° C., 100 mL) was stirred at 90° C. for 16 h. It was cooled to rt, concentrated, and purified by silica gel column chromatography using 0-10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 287.1 [M+H] + .  1 H-NMR (300 MHz, DMSO-d 6 ): δ 8.06 (s, 1H), 7.40-7.25 (m, 1H), 7.14 (s, 2H), 6.82 (d, J=5.9 Hz, 1H), 6.60 (d, J=3.7 Hz, 1H), 6.34 (dd, J=16.2, 2.1 Hz, 1H), 4.88 (t, J=5.7 Hz, 1H), 4.27 (ddd, J=9.9, 6.2, 3.6 Hz, 1H), 4.08 (dq, J=6.8, 4.1, 3.5 Hz, 1H), 3.78 (dt, J=11.1, 5.4 Hz, 1H), 3.62 (dt, J=11.4, 5.8 Hz, 1H). 
     Step 3: N-(7-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-hydroxymethyl)tetrahydrofuran-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,5R)-5-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-4,4-difluoro-2-(hydroxymethyl)tetrahydrofuran-3-ol (900 mg, 3.14 mmol) in pyridine (15 mL) at 0° C. was added chlorotrimethylsilane (3.42 g, 31.4 mmol). It was warmed to rt over 1 h and benzoyl chloride (663 mg, 4.72 mmol) was added dropwise. After 2 h, NH 4 OH (28%, 15.00 mL) was added, and it was stirred for 0.5 h. The resulting mixture was concentrated, and the residue was purified by silica gel column chromatography using 0-10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 391.1 [M+H] + .  1 H-NMR (300 MHz, DMSO-d 6 ): δ 8.61 (s, 1H), 8.08-7.98 (m, 2H), 7.97-7.91 (m, 1H), 7.67-7.51 (m, 2H), 7.50-7.47 (m, 1H), 6.70 (d, J=3.9 Hz, 1H), 6.56 (dd, J=15.6, 1.5 Hz, 1H), 4.32 (dd, J=9.4, 3.6 Hz, 1H), 4.16 (d, J=5.6 Hz, 1H), 3.80 (dd, J=11.5, 5.2 Hz, 1H), 3.66 (dd, J=11.5, 6.5 Hz, 1H), 3.12 (s, 2H). 
     Step 4. N-(7-((2R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3,3-difluoro-4-hydroxytetrahydrofuran-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(7-((2S,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)-tetrahydrofuran-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)benzamide (1.1 g, 2.82 mmol) in pyridine (12 mL) at 0° C. was added 4,4′-(chloro(phenyl)methylene)-bis(methoxybenzene) (0.955 g, 2.82 mmol). It was warmed to RT and stirred for 3 h. The mixture was concentrated. The product was purified by silica gel column chromatography using 0-10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 693.3 [M+H] + .  1 H-NMR (300 MHz, DMSO-d 6 ): δ 11.25 (s, 1H), 8.67 (s, 1H), 8.09-8.01 (m, 2H), 7.60-7.48 (m, 2H), 7.47-7.36 (m, 3H), 7.33-7.18 (m, 7H), 6.91-6.78 (m, 4H), 6.75-6.57 (m, 3H), 5.76 (s, 1H), 4.55-4.33 (m, 2H), 3.74 (s, 6H), 3.44 (t, J=8.7 Hz, 1H), 3.35 (s, 1H). 
     Preparation 16: N-(9-((2R,3S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4,4-difluoro-3-hydroxytetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,4S)-4-(benzyloxy)-4-((R)-2,2-dimethyl-1,3-dioxolan-4-yl)-3,3-difluoro-2-hydroxybutyl benzoate 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,4S)-4-(benzyloxy)-4-((R)-2,2-dimethyl-1,3-dioxolan-4-yl)-3,3-difluorobutane-1,2-diol (3.50 g, 10.5 mmol) in CH 2 Cl 2  (52 mL) and pyridine (26 mL) at −70° C. was added benzoyl chloride (1.48 g, 10.5 mmol) in CH 2 Cl 2  (11 mL) dropwise over 50 min. After 2 h, methanol (150 mL) was added. The mixture was stirred at RT for 0.5 h. Water (200 mL) was added. Layers were separated, and the aq layer was extracted with ether (4×150 mL). The combined organic layers were washed with aq HCl (1 N, 2×150 mL), sat aq NaHCO 3  (2×150 mL) and brine (2×150 mL). It was dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography (EtOAc/petroleum ether=1/10) to give the product.  1 H-NMR (400 MHz, CDCl 3 ): δ 8.11-8.01 (m, 2H), 7.61-7.55 (m, 1H), 7.48-7.31 (m, 7H), 4.89-4.53 (m, 4H), 4.46-4.41 (m, 1H), 4.40-4.29 (m, 1H), 4.17-4.02 (m, 2H), 3.98-3.84 (m, 0.5H), 3.74-3.66 (m, 0.5H), 1.46 (s, 3H), 1.28 (s, 3H).  19 F-NMR: (376 MHz, CDCl 3 ): δ −106.8 (d, J=270.7 Hz, 1F), −119.2 (d, J=270.7 Hz, 1F). 
     Step 2: ((2R,4S)-4-(benzyloxy)-3,3-difluoro-5-hydroxytetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     (2R,4 S)-4-(benzyloxy)-4-((R)-2,2-dimethyl-1,3-dioxolan-4-yl)-3,3-difluoro-2-hydroxybutyl benzoate (3.00 g, 6.87 mmol) was dissolved in aq AcOH (75%, 66 mL). It was stirred at 50° C. for 3 h. It was partly concentrated. The residue was redissolved in acetone (33 mL). To the solution at rt was added sodium periodate (1.20 g, 5.61 mmol) in water (33 mL). After 1.5 h, the solid formed was filtered off and washed with acetone. The filtrate was concentrated. Water and CH 2 Cl 2  were added, and layers were separated. The aq layer was extracted with CH 2 Cl 2  (4×150 mL). The combined organic layers were dried (Na 2 SO 4 ), concentrated, and purified by silica gel column chromatography (ethyl acetate/petroleum ether=1/5) to give the product.  1 H-NMR (400 MHz, CDCl 3 ): δ 8.05-8.01 (m, 2H), 7.59-7.52 (m, 1H), 7.46-7.35 (m, 7H), 5.49-5.42 (m, 1H), 4.99-4.72 (m, 1H), 4.67-4.47 (m, 4H), 4.11-3.80 (m, 1H).  19 F-NMR: (376 MHz, CDCl 3 ): δ −117.1 (d, J=240.6 Hz, 1F), −117.9 (d, J=251.9 Hz, 1F). 
     Step 3: ((2R,4S)-5-acetoxy-4-(benzyloxy)-3,3-difluorotetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,4S)-4-(benzyloxy)-3,3-difluoro-5-hydroxytetrahydrofuran-2-yl)methyl benzoate (2.40 g, 6.59 mmol) in CH 2 Cl 2  (66 mL) at rt was added N,N-dimethylpyridin-4-amine (0.080 g, 0.659 mmol) and acetic anhydride (4.03 g, 39.5 mmol) dropwise. After 6 h, it was quenched by addition of sat aq NaHCO 3  (30 mL). Layers were separated, and the aq layer was extracted with CH 2 Cl 2  (3×150 mL). The combined organic layers were washed with water (2×150 mL) and brine (2×100 mL), dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography (ethyl acetate/petroleum ether=1/7) to give the product.  1 H-NMR (300 MHz, CDCl 3 ): δ 8.08-7.89 (m, 2H), 7.61-7.48 (m, 1H), 7.47-7.25 (m, 7H), 6.15 (d, J=6.0 Hz, 1H), 4.89-4.75 (m, 1H), 4.73-4.40 (m, 4H), 4.18-4.02 (m, 1H), 1.98 (s, 3H).  19 F-NMR: (282 MHz, CDCl 3 ): δ −116.5 (d, J=248.2 Hz, 1F), −120.9 (d, J=248.2 Hz, 1F). 
     Step 4: ((2R,4S)-5-acetoxy-3,3-difluoro-4-hydroxytetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,4S)-5-acetoxy-4-(benzyloxy)-3,3-difluorotetrahydrofuran-2-yl)methyl benzoate (2.50 g, 6.15 mmol) in EtOAc (60 mL) was added sodium bromate (5.57 g, 36.9 mmol) in water (46 mL). The mixture was stirred vigorously, and to it was added sodium dithionite (6.43 g, 36.9 mmol) in water (92 mL) dropwise over 1 h. After 5 h, layers were separated, and the aq layer was extracted with EtOAc (5×150 mL). The combined organic layers were washed with sat aq Na 2 S 2 O 3  (2×150 mL) and brine (2×150 mL), dried (Na 2 SO 4 ), concentrated, and purified by silica gel column chromatography (ethyl acetate/petroleum ether=1/5) to give the product.  1 H-NMR (300 MHz, CDCl 3 ): δ 8.10-7.89 (m, 2H), 7.63-7.50 (m, 1H), 7.48-7.30 (m, 2H), 6.09 (d, J=6.0 Hz, 1H), 4.71-4.42 (m, 3H), 4.36-4.26 (m, 1H), 2.04 (s, 3H). 19F-NMR: (282 MHz, CDCl 3 ): δ −119.5 (d, J=248.2 Hz, 1F), −122.0 (d, J=248.2 Hz, 1F). 
     Step 5: (3S,5R)-5-((benzoyloxy)methyl)-4,4-difluorotetrahydrofuran-2,3-diyl diacetate 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,4S)-5-acetoxy-3,3-difluoro-4-hydroxytetrahydrofuran-2-yl)methyl benzoate (2.00 g, 6.32 mmol) in CH 2 Cl 2  (84 mL) at rt was added DMAP (0.08 g, 0.632 mmol) and acetic anhydride (3.87 g, 37.9 mmol) dropwise. After 6 h, it was quenched by addition of sat aq NaHCO 3  (30 mL). Layers were separated, and the aq layer was extracted with CH 2 C 12  (3×140 mL). The combined organic layers were washed with water (2×140 mL) and brine (2×140 mL), dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography (ethyl acetate/petroleum ether=1/6) to give the product.  1 H-NMR (400 MHz, CDCl 3 ): δ 8.11-8.01 (m, 2H), 7.63-7.54 (m, 1H), 7.50-7.41 (m, 2H), 6.20 (d, J=4.0 Hz, 1H), 5.39 (d, J=8.0 Hz, 1H), 4.69-4.48 (m, 3H), 2.23 (s, 3H), 2.08 (s, 3H).  19 F-NMR: (376 MHz, CDCl 3 ): δ −117.6 (d, J=251.9 Hz, 1F), −119.5 (d, J=251.9 Hz, 1F). 
     Step 6: ((2R,4S,5R)-4-acetoxy-5-(6-chloro-2-isobutyramido-9H-purin-9-yl)-3,3-difluorotetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a solution of (3 S,5R)-5-((benzoyloxy)methyl)-4,4-difluorotetrahydrofuran-2,3-diyl diacetate (2.20 g, 6.14 mmol) and N-(6-chloro-9H-purin-2-yl)isobutyramide (1.77 g, 7.37 mmol) in ACN (80 mL) at 0° C. was added 2,3,4,6,7,8,9,10-octahydropyrimido[1,2-a]azepine (2.80 mL, 18.4 mmol). After 0.5 h, trimethylsilyl trifluoromethanesulfonate (6.82 mL, 36.8 mmol) was added dropwise to the reaction at 0° C. After 0.5 h, it was heated at 80° C. for 16 h. The reaction was then quenched by the addition of water (150 mL). Layers were separated, and the aq layer was extracted with EtOAc (3×150 mL). The combined organic layers were washed with sat aq NaHCO 3  (2×150 mL) and brine (2×150 mL), dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography (ethyl acetate/petroleum ether=1/1) to give the product.  1 H-NMR (400 MHz, CDCl 3 ): δ 8.10 (s, 1H), 8.08-7.98 (m, 2H), 7.64-7.53 (m, 1H), 7.51-7.40 (m, 2H), 6.25 (d, J=4.0 Hz, 1H), 5.98-5.93 (m, 1H), 4.85-4.53 (m, 3H), 2.92-2.80 (m, 1H), 2.22 (s, 3H) 1.28 (d, J=4.0 Hz, 6H).  19 F-NMR: (376 MHz, CDCl 3 ): δ −116.7 (d, J=248.2 Hz, 1F), −118.1 (d, J=248.2 Hz, 1F). 
     Step 7: ((2R,4S,5R)-5-(2-acetamido-6-oxo-1,6-dihydro-9H-purin-9-yl)-4-acetoxy-3,3-difluorotetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,4S,5R)-4-acetoxy-5-(6-chloro-2-isobutyramido-9H-purin-9-yl)-3,3-difluorotetrahydrofuran-2-yl)methyl benzoate (1.80 g, 3.35 mmol) in AcOH (29 mL) was added Sodium acetate (1.37 g, 16.7 mmol) and acetic anhydride (29 mL). The reaction was stirred at 125° C. for 2.5 h. It was cooled to rt, and MeOH (50 mL) was added. The mixture was concentrated under reduced pressure, and the residue was coevaporated with ethanol (2×50 mL). DCM (150 mL) and water (150 mL) were added, and layers were separated. The organic phase was washed with sat aq NaHCO 3  (2×150 mL), dried (Na 2 SO 4 ), and concentrated to give the product. LCMS (ES, m/z): 492.1 [M+H] + . 
     Step 8: 2-amino-9-((2R,3S,5R)-4,4-difluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To ((2R,4S,5R)-5-(2-acetamido-6-oxo-1,6-dihydro-9H-purin-9-yl)-4-acetoxy-3,3-difluorotetrahydrofuran-2-yl)methyl benzoate (neat, 1.80 g, 3.66 mmol) was added NH 3  in MeOH (7 M, 90 mL, MeOH). It was stirred at rt for 60 h. It was concentrated and purified by reverse phase (C18) chromatography eluting with 5-20% MeCN in aq NH 4 HCO 3  (5 mM) to give the product.  1 H-NMR (300 MHz, DMSO-d 6 ): δ 10.7 (s, 1H), 7.95 (s, 1H), 6.56-6.44 (m, 3H), 5.62 (d, J=6.0 Hz, 1H), 5.32 (t, J=5.4 Hz, 1H), 4.90-4.77 (m, 1H), 4.23-4.08 (m, 1H), 3.68-3.52 (m, 2H).  19 F-NMR: (282 MHz, DMSO-d 6 ): δ −113.1 (d, J=234.1 Hz, 1F), −121.8 (d, J=234.1 Hz, 1F). 
     Step 9. N-(9-((2R,3S,5R)-4,4-difluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     2-amino-9-((2R,3 S,5R)-4,4-difluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-1,9-dihydro-6H-purin-6-one (800 mg, 2.64 mmol) was co-evaporated with pyridine (3×3 mL). It was re-suspended in pyridine (13 mL). To the mixture at 0° C. was added chlorotrimethylsilane (1.686 mL, 13.19 mmol) dropwise. It was warmed to rt and stirred for 2 h. The reaction was cooled to 0° C., and isobutyric anhydride (0.656 mL, 3.96 mmol) was added dropwise. It was warmed to rt, stirred for 2 h, and then water (4 mL) and NH 4 OH (8 mL) were added to the reaction. After 30 min, it was concentrated. The residue was purified by flash column chromatography with 0-10% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 374.1 [M+H] + .  1 H-NMR: (300 MHz, DMSO-d 6 ) δ 12.11 (s, 1H), 11.69 (s, 1H), 8.30 (s, 1H), 6.58 (d, J=6.0 Hz, 1H), 5.74 (dd, J=9.0, 3.0 Hz, 1H), 5.33 (t, J=6.0 Hz, 1H), 4.96-4.83 (m, 1H), 4.26-4.17 (m, 1H), 3.72-3.62 (m, 2H), 2.80-2.71 (m, 1H), 1.11 (d, J=9.0 Hz, 6H). 
     Step 10: N-(9-((2R,3S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4,4-difluoro-3-hydroxytetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     N-(9-((2R,3 S,5R)-4,4-difluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (640 mg, 1.714 mmol) was co-evaporated with pyridine (3×3 mL) and then re-suspended in pyridine (5.7 mL). To the suspension was added 4,4′-(chloro(phenyl)methylene)bis(methoxybenzene) (639 mg, 1.886 mmol), and it was stirred for 16 h. Then, it was concentrated and then, co-evaporated with toluene (3×20 mL). The crude was purified by silica column chromatography eluting with 1 to 30% MeOH in CH 2 Cl 2  (containing 1% Et 3 N) to give the product. LCMS (ES, m/z): 676.3 [M+H] + .  1 H-NMR: (300 MHz, DMSO-d 6 ) δ 12.11 (s, 1H), 11.61 (s, 1H), 8.15 (s, 1H), 7.34 (J=6.0, 3.0 Hz, 2H), 7.28-7.19 (m, 7H), 6.85-6.80 (m, 4H), 6.71 (d, J=6.0 Hz, 1H), 5.78 (d, J=6.0 Hz, 1H), 5.13-5.05 (m, 1H), 4.46-4.39 (m, 1H), 3.71 (s, 6H), 3.46-3.40 (m, 1H), 3.22-3.18 (m, 1H), 2.78-2.70 (m, 1H), 1.11 (d, J=9.0 Hz, 6H). 
     Preparation 17: N-(9-((2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-4-fluoro-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: 2-amino-9-((4aR,6R,7R,7aR)-2,2-di-tert-butyl-7-hydroxytetrahydro-4H-thieno[3,2-d][1,3,2]dioxasilin-6-yl)-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To a stirred suspension of 2-amino-9-((2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-1H-purin-6(9H)-one (15 g, 50.1 mmol) in DMF (150 mL) at 0° C. under Ar was injected di-tert-butylsilanediyl bis(trifluoromethanesulfonate) (26.5 g, 60.1 mmol). The resulting solution was stirred at rt for 1 h. It was used for the next reaction step directly without purification. LCMS (ES, m/z): 440.2 [M+H] + . 
     Step 2: 2-amino-9-((4aR,6R,7R,7aR)-2,2-di-tert-butyl-7-((tert-butyldimethylsilyl)oxy) tetrahydro-4H-thieno[3,2-d][1,3,2]dioxasilin-6-yl)-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from the previous step at 0° C. was added 1H-imidazole (17.05 g, 251 mmol) in one portion. The mixture was stirred rt for 0.5 h. tert-butylchlorodimethylsilane (15.10 g, 100 mmol) was added to the mixture, and it was stirred at 60° C. for 16 h. Then, the volatile components were removed under reduced pressure. The solid was suspended in cold methanol (75 mL), filtered, and washed with cold methanol (2×30 mL). The solid was kept under reduced pressure to give the product. LCMS (ES, m/z): 554.4 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 10.80 (s, 1H), 7.98 (s, 1H), 6.49 (s, 2H), 5.53 (s, 1H), 4.46 (d, J=3.2 Hz, 1H), 4.42 (d, J=9.9 Hz, 1H), 4.34 (dd, J=9.9, 4.7 Hz, 1H), 4.21 (t, J=10.5 Hz, 1H), 3.70-3.64 (m, 1H), 1.04 (s, 9H), 1.00 (s, 9H), 0.92 (s, 9H), 0.19 (s, 3H), 0.11 (s, 3H). 
     Step 3: N-(9-((4aR,6R,7R,7aR)-2,2-di-tert-butyl-7-((tert-butyldimethylsilyl)oxy)tetrahydro-4H-thieno[3,2-d][1,3,2]dioxasilin-6-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     2-amino-9-((4aR,6R,7R,7aS)-2,2-di-tert-butyl-7-((tert-butyldimethylsilyl)oxy)tetrahydro-4H-thieno[3,2-d][1,3,2]dioxasilin-6-yl)-1H-purin-6(9H)-one (29.1 g, 52.5 mmol) was co-evaporated with dry pyridine (3×50 mL) and re-dissolved in pyridine (70 mL) and dichloromethane (210 mL). The mixture was charged with Ar and cooled to 0° C. To the mixture was added isobutyryl chloride (11.20 g, 105 mmol). It was stirred at rt for 4 h. It was concentrated under reduced pressure. The solid was suspended in cold methanol (100 mL), filtered, and washed with cold methanol (3×50 mL). The solid was kept under reduced pressure to give the product. LCMS (ES, m/z): 624.1 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 12.13 (s, 1H), 11.39 (s, 1H), 8.32 (s, 1H), 5.61 (s, 1H), 4.66 (d, J=3.4 Hz, 1H), 4.48 (d, J=9.9 Hz, 1H), 4.38-4.33 (m, 1H), 4.21 (t, J=9.9 Hz, 1H), 3.76-3.70 (m, 1H), 2.84-2.80 (m, 1H), 1.13 (d, J=6.7 Hz, 6H), 1.06 (s, 9H), 1.01 (s, 9H), 0.91 (s, 9H), 0.16 (s, 3H), 0.11 (s, 3H). 
     Step 4. N-(9-((2R,3R,4S,5R)-3-((tert-butyldimethylsilyl)oxy)-4-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     HF-Pyridine (26.6 g, 188 mmol) at 0° C. was diluted with pyridine (29 mL). The resulting solution was added slowly to a stirred suspension of N-(9-((4aR,6R,7R,7aS)-2,2-di-tert-butyl-7-((tert-butyldimethylsilyl)oxy)tetrahydro-4H-thieno[3,2-d][1,3,2]dioxasilin-6-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (29.3 g, 47.0 mmol) in CH 2 Cl 2  (290 mL) at 0° C. It was stirred at 0° C. for 2 h. The reaction mixture was diluted with CH 2 Cl 2  (500 mL). It was washed with water (500 mL) and sat aq NaHCO 3  (500 mL). The organic layer was dried (Na 2 SO 4 ) and concentrated to give the product. LCMS (ES, m/z): 484.4 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 12.05 (s, 1H), 11.73 (s, 1H), 8.43 (s, 1H), 5.89 (d, J=7.9 Hz, 1H), 5.34 (d, J=3.9 Hz, 1H), 5.27 (t, J=5.6 Hz, 1H), 4.60 (dd, J=8.1, 3.2 Hz, 1H), 4.19-4.17 (m, 1H), 3.80-3.74 (m, 1H), 3.66-3.60 (m, 1H), 3.30 (t, J=8.0 Hz, 1H), 2.80-2.73 (m, 1H), 1.12 (d, J=6.7 Hz, 6H), 0.68 (s, 9H), −0.06 (s, 3H), −0.29 (s, 3H). 
     Step 5. N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-((tert-butyldimethylsilyl)oxy)-4-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     N-(9-((2R,3R,4S,5R)-3-((tert-butyldimethylsilyl)oxy)-4-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (21 g, 43.4 mmol) was co-evaporated with pyridine (3×50 mL) and dissolved in pyridine (210 mL). 4,4′-(chloro(phenyl)methylene)bis(methoxybenzene) (16.2 g, 47.8 mmol) was added, and it was stirred at rt for 3 h and then concentrated under reduced pressure and co-evaporated with toluene (3×50 mL). The crude was purified by silica gel chromatography eluting with 0-40% EtOAc in CH 2 Cl 2  (containing 0.1% Et 3 N) to give the product. LCMS (ES, m/z): 786.4 [M+H] + .  1 H-NMR (300 MHz, DMSO-d 6 ): δ 12.06 (s, 1H), 11.71 (s, 1H), 8.19 (s, 1H), 7.44-7.42 (m, 2H), 7.37-7.22 (m, 7H), 6.92 (d, J=8.5 Hz, 4H), 5.87 (d, J=7.2 Hz, 1H), 5.44 (d, J=4.4 Hz, 1H), 4.40 (dd, J=7.3, 3.3 Hz, 1H), 4.19 (d, J=5.9 Hz, 1H), 3.75 (s, 6H), 3.54-3.35 (m, 2H), 3.34-3.28 (m, 1H), 2.83-2.71 (m, 1H), 1.11 (d, J=6.7 Hz, 6H), 0.70 (s, 9H), −0.08 (s, 3H), −0.29 (s, 3H). 
     Step 6: N-(9-((2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-((tert-butyldimethylsilyl)oxy)-4-fluorotetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)-methyl)-3-((tert-butyldimethylsilyl)oxy)-4-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (22 g, 28.0 mmol) in CH 2 Cl 2  (220 mL) at 0° C. was added pyridine (18.11 mL, 224 mmol) and DAST (14.79 mL, 112 mmol) dropwise. The reaction was allowed to warm to rt and stirred for 7 h. It was then cooled to 0° C. and quenched by slow addition of sat aq NaHCO 3  (500 mL). More CH 2 Cl 2  (500 mL) was added, and the phases were separated. The organic phase was washed with sat aq NaHCO 3  (3×200 mL) and brine (300 mL), dried (Na 2 SO 4 ), concentrated, and purified by reverse phase (C18) chromatography eluting with 45-95% of ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 788.2 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 12.06 (s, 1H), 11.56 (s, 1H), 8.02 (s, 1H), 7.44-7.42 (m, 2H), 7.34-7.23 (m, 7H), 6.92-6.89 (m, 4H), 5.71 (d, J=4.9 Hz, 1H), 5.14 (dt, J=51.0, 5.6 Hz, 1H), 5.01-4.96 (m, 1H), 3.88-3.85 (m, 1H), 3.75 (s, 6H), 3.57 (t, J=8.8 Hz, 1H), 3.50 (dd, J=10.0, 5.3 Hz, 1H), 2.81-2.74 (m, 1H), 1.12 (d, J=6.8 Hz, 6H), 0.77 (s, 9H), 0.00 (s, 3H), −0.16 (s, 3H). F-NMR: (376 MHz, DMSO-d 6 , ppm) 6-193.99 (s, 1F). 
     Step 7: N-(9-((2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(9-((2R,3R,4R, SR)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy) methyl)-3-((tert-butyldimethylsilyl)oxy)-4-fluorotetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (7.2 g, 6.85 mmol) in THF (70 mL) at rt was added TBAF (1.0M in THF, 8.22 mL, 8.22 mmol) dropwise. It was stirred at rt for 30 min, the solution was concentrated, and CH 2 Cl 2  (300 mL) was added. The mixture was washed with NaHCO 3  (3×200 mL) and brine (200 mL), and the organic phase was separated, dried (Na 2 SO 4 ), concentrated and purified by reverse phase (C18) chromatography eluting with 0-95% of ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 674.3 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 12.02 (br, 1H), 7.85 (s, 1H), 7.44-7.41 (m, 2H), 7.36-7.24 (m, 7H), 6.94-6.90 (m, 4H), 6.33 (bs, 1H), 5.78 (d, J=2.7 Hz, 1H), 5.19 (dt, J=50.2, 4.0 Hz, 1H), 4.80-4.75 (m, 1H), 4.10-4.02 (m, 1H), 3.76 (s, 6H), 3.55 (dd, J=9.3, 5.6 Hz, 1H), 3.44 (t, J=8.9 Hz, 1H), 2.79-2.71 (m, 1H), 1.12 (d, J=6.8 Hz, 6H). F-NMR: (376 MHz, DMSO-d 6 ) δ −194.75 (s). 
     Preparation 18: N-(9-((2R,3R,5S)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: (3R,4S,5R)-4-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     To a solution of (6aR,9R,9aS)-2,2,4,4-tetraisopropyltetrahydro-6H-thieno[3,2-f][1,3,5,2,4]trioxadisilocin-9-yl 2,4-dimethoxybenzoate (60 g, 108 mmol) in THF (500 mL) were added AcOH (13.59 g, 226 mmol) and TBAF in THF (1 M, 226 mL, 226 mmol). After 1 h, it was concentrated under reduced pressure and purified by silica gel column chromatography eluting with 0-20% EtOAc in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 315.1 [M+H] + . 1H-NMR (400 MHz, CDCl 3 ) δ 7.87 (d, J=8.7 Hz, 1H), 6.58-6.46 (m, 2H), 5.51 (dt, J=5.0, 3.7 Hz, 1H), 4.31 (td, J=6.9, 3.7 Hz, 1H), 3.88 (d, J=12.0 Hz, 8H), 3.58 (dt, J=7.1, 4.7 Hz, 1H), 3.26 (dd, J=12.2, 5.0 Hz, 1H), 3.15-3.01 (m, 2H), 2.31 (s, 1H). 
     Step 2: (3R,4S,5R)-5-(((tert-butyldiphenylsilyl)oxy)methyl)-4-hydroxytetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     To a solution of (3R,4S,5R)-4-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (33 g, 105 mmol) in pyridine (300 mL) was added tert-butylchlorodiphenylsilane (43.3 g, 157 mmol). It was stirred at rt for 4 h. Then, water (300 mL) was added. Layers were separated, and the aq layer was extracted with CH 2 Cl 2  (3×300 mL). The combined organic layer was washed with brine (300 mL), dried (Na 2 SO 4 ), concentrated, and purified by silica gel column chromatography eluting with 1 to 10% EtOAc in petroleum ether to give the product. LCMS (ES, m/z): 575.3 [M+Na] + .  1 H-NMR (400 MHz, DMSO-d 6 ) δ 7.83 (d, J=8.7 Hz, 1H), 7.68 (t, J=5.5 Hz, 5H), 7.54-7.38 (m, 6H), 6.69-6.60 (m, 2H), 5.40 (d, J=5.6 Hz, 1H), 5.35-5.29 (m, 1H), 4.12 (s, 1H), 4.05 (d, J=7.3 Hz, 1H), 3.85 (d, J=7.2 Hz, 6H), 3.78-3.66 (m, 1H), 3.55 (d, J=7.2 Hz, 1H), 3.14 (dd, J=11.0, 5.0 Hz, 1H), 2.86-2.77 (m, 1H), 1.03 (s, 9H). 
     Step 3: (3R,4S,5R)-4-((1H-imidazole-1-carbonothioyl)oxy)-5-(((tert-butyldiphenylsilyl)oxy)methyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     To a solution of (3R,4S,5R)-5-(((tert-butyldiphenylsilyl)oxy)methyl)-4-hydroxytetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (48 g, 87 mmol) in dichloroethane (500 mL) was added di(1H-imidazol-1-yl)methanethione (20.12 g, 113 mmol). It was heated at 85° C. under Ar for 1 h. Then, it was concentrated and used in the next step without purification. LCMS (ES, m/z): 663.2 [M+H] + . 
     Step 4: (3R,5S)-5-(((tert-butyldiphenylsilyl)oxy)methyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     To a solution of (3R,4S,5R)-4-((1H-imidazole-1-carbonothioyl)oxy)-5-(((tert-butyldiphenylsilyl)oxy)methyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (crude, 57.6 g, 87 mmol) in THF (40 mL) and toluene (200 mL) was added tributylstannane (139 g, 478 mmol). It was heated at 95° C., and 2,2′-(diazene-1,2-diyl)bis(2-methylpropanenitrile) (1.427 g, 8.69 mmol) in toluene (200 mL) was added over 30 min. After 1 h, the resulting mixture was concentrated and purified by silica gel column chromatography eluting with 0 to 10% EtOAc in petroleum ether to give the product. LCMS (ES, m/z): 537.3 [M+H] + .  1 H-NMR (400 MHz, CDCl 3 ) δ 7.88 (d, J=8.6 Hz, 1H), 7.77-7.67 (m, 4H), 7.50-7.36 (m, 6H), 6.58-6.48 (m, 2H), 5.70 (p, J=3.8 Hz, 1H), 3.95-3.74 (m, 10H), 3.28 (dd, J=12.0, 4.6 Hz, 1H), 3.10-3.02 (m, 1H), 2.49-2.39 (m, 1H), 1.92 (ddd, J=13.3, 8.6, 4.1 Hz, 1H), 1.09 (s, 9H). 
     Step 5: (JR, 3R,5S)-5-(((tert-butyldiphenylsilyl)oxy)methyl)-1-oxidotetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     To a solution of Ti(OiPr) 4  (23.29 mL, 78 mmol) in CH 2 Cl 2  (130 mL) under Ar was added diethyl (L)-tartrate (38.3 mL, 224 mmol) dropwise. After 10 min, the mixture was cooled to −20° C., and then TBHP in decane (˜5.5M, 27.1 mL, 149 mmol) was added dropwise. After 5 min, a solution of (3R,5 S)-5-(((tert-butyldiphenylsilyl)oxy)methyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (40 g, 74.5 mmol) in CH 2 Cl 2  (130 mL) was added to the reaction at −20° C. The resulting mixture was stirred at −20° C. for 16 h. It was quenched by the addition of ice water (300 mL) and allowed to warm up to rt. The precipitate was filtered off and washed with EtOAc (3×300 mL). The filtrate was washed with water (3×200 mL). The aq layer was extracted with EtOAc (400 mL). The combined organic layer was dried (Na 2 SO 4 ), concentrated and purified by flash chromatography eluting with 0 to 70% EtOAc in petroleum ether to give the product (mixture of two isomers). LCMS (ES, m/z): 553.2 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ) δ 7.81 (d, J=8.7 Hz, 1H), 7.75-7.61 (m, 4H), 7.54-7.39 (m, 6H), 6.67-6.56 (m, 2H), 5.66 (q, J=3.8 Hz, 1H), 4.12 (dt, J=10.5, 4.4 Hz, 1H), 3.92-3.79 (m, 8H), 3.58-3.42 (m, 1H), 3.20-3.09 (m, 1H), 2.97 (d, J=15.0 Hz, 1H), 2.05 (ddd, J=14.5, 10.5, 4.3 Hz, 1H), 1.02 (s, 9H). 
     Step 6: (3R,5S)-2-acetoxy-5-(((tert-butyldiphenylsilyl)oxy)methyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     A solution of (3R,5S)-2-acetoxy-5-(((tert-butyldiphenylsilyl)oxy)methyl)-tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (21 g, 34.2 mmol) in acetic anhydride (210 mL) was heated at 110° C. After stirring of 3.5 h, the reaction mixture was cooled to rt and concentrated. The residue was purified by silica gel column chromatography eluting with 0% to 20% EtOAc in petroleum ether to give the product. LCMS (ES, m/z): 535.3 [M-OAc] + .  1 H-NMR (400 MHz, DMSO-d 6 ) δ 7.76-7.61 (m, 5H), 7.46 (dq, J=7.6, 4.5, 3.7 Hz, 6H), 6.68-6.58 (m, 2H), 6.22 (d, J=4.3 Hz, 0.65H), 5.94 (s, 0.28H), 5.51-5.46 (m, 0.33H), 5.38 (ddd, J=11.1, 7.2, 4.3 Hz, 0.65H), 3.96-3.61 (m, 9H), 2.40-2.21 (m, 2H), 2.03 (d, J=1.6 Hz, 3H), 1.01 (s, 9H). 
     Step 7: (3R,5S)-5-(((tert-butyldiphenylsilyl)oxy)methyl)-2-(6-chloro-2-isobutyramido-9H-purin-9-yl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     To a solution of N-(6-chloro-9H-purin-2-yl)isobutyramide (10.27 g, 42.9 mmol) in toluene (600 mL) at 0° C. was added trimethylsilyl N-(trimethylsilyl)acetimidate (23.26 g, 114 mmol). It was heated at 80° C. for 1 h and was cooled to 0° C. again. To the reaction was then added a solution of (3R,5S)-2-acetoxy-5-(((tert-butyldiphenylsilyl)oxy)methyl)-tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (17 g, 28.6 mmol) in toluene (600 mL) and trimethylsilyl trifluoromethanesulfonate (19.06 g, 86 mmol). It was heated to 80° C. and stirred under Ar for 12 h. At that time, the reaction was cooled to rt, and sat aq NaHCO 3  (400 mL) was added. Layers were separated, and the aq layer was extracted with EtOAc (4×1000 mL). The combined organic phase was dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography eluting with 10% to 40% EtOAc in petroleum ether to give the product (mixture of a and 3 isomers). LCMS (ES, m/z): 774.3 [M+H] + .  1 H-NMR (400 MHz, CDCl 3 ) δ 8.48 (s, 0.32H), 8.35 (s, 0.69H), 7.97-7.83 (m, 1.67H), 7.70 (dq, J=8.4, 1.5 Hz, 4H), 7.54 (d, J=8.7 Hz, 0.33H), 7.49-7.36 (m, 6H), 6.57-6.36 (m, 2.5H), 6.18 (d, J=2.4 Hz, 0.7H), 5.87-5.80 (m, 0.35H), 5.73 (q, J=3.3 Hz, 0.75H), 4.23-4.01 (m, 1.2H), 3.98-3.74 (m, 7.8H), 3.11 (s, 0.73H), 2.95 (s, 0.37H), 2.57-2.36 (m, 1.75H), 2.30-2.20 (m, 0.34H), 1.23 (d, J=6.8 Hz, 2.19H), 1.19 (dd, J=6.8, 3.5 Hz, 4.38H), 1.09 (d, J=1.7 Hz, 9H). 
     Step 8. (2R,3R,5S)-2-(6-chloro-2-isobutyramido-9H-purin-9-yl)-5-(hydroxymethyl)-tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate 
     
       
         
         
             
             
         
       
     
     To a solution of (3R,5 S)-5-(((tert-butyldiphenylsilyl)oxy)methyl)-2-(6-chloro-2-isobutyramido-9H-purin-9-yl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (20 g, 25.8 mmol) in THF (135 mL) was added TBAF in THF (1 M, 31 mL, 31 mmol) dropwise. After 1 h, the reaction mixture was concentrated and purified by column chromatography using 1% to 10% MeOH in CH 2 Cl 2  as the eluent to give a mixture of two isomers. It was re-purified by reverse phase (C18) chromatography eluting with 10 to 45% ACN in aq NH 4 CO 3  (5 mM) to give the product. LCMS (ES, m/z): 536.2 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ) δ 10.80 (s, 1H), 8.83 (s, 1H), 7.72 (d, J=8.7 Hz, 1H), 6.65-6.55 (m, 2H), 6.18 (d, J=2.5 Hz, 1H), 5.80 (q, J=3.5 Hz, 1H), 5.22 (t, J=5.1 Hz, 1H), 3.93-3.67 (m, 9H), 2.85 (p, J=6.9 Hz, 1H), 2.70 (ddd, J=13.4, 8.5, 4.5 Hz, 1H), 2.36 (dt, J=14.1, 5.0 Hz, 1H), 1.06 (dd, J=6.8, 3.3 Hz, 6H). 
     Step 9: 2-amino-9-((2R,3R,5S)-3-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,5 S)-2-(6-chloro-2-isobutyramido-9H-purin-9-yl)-5-(hydroxymethyl)tetrahydrothiophen-3-yl 2,4-dimethoxybenzoate (6.0 g, 11.19 mmol) in MeOH (300 mL) were added 2-mercaptoethanol (3.50 g, 44.8 mmol) and NaOMe (10.08 g, 56 mmol, 30% in MeOH). It was heated at 60° C. for 16 h, cooled to rt, and conc. HCl (4 mL) was added. The resulting mixture was concentrated, and water (100 mL) and EtOAc (100 mL) were added. Layers were separated, and the aq layer was extracted with EtOAc (3×100 mL). The aq layer was basified with NaHCO 3  (solid) to ˜pH 8 and stirred at rt for 1 h. The precipitate was filtered and kept under reduced pressure to give the product. LCMS (ES, m/z): 284.1 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ) δ 10.57 (s, 1H), 7.98 (s, 1H), 6.46 (s, 2H), 5.57 (dd, J=10.9, 3.9 Hz, 2H), 5.12 (t, J=5.4 Hz, 1H), 4.48 (p, J=4.1 Hz, 1H), 3.78-3.53 (m, 3H), 2.11-1.99 (m, 2H). 
     Step 10: N-(9-((2R,3R,5S)-3-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     2-amino-9-((2R,3R,5 S)-3-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-1,9-dihydro-6H-purin-6-one (580 mg, 2.047 mmol) was co-evaporated with pyridine (3×20 mL) and then re-dissolved in pyridine (20 mL). The mixture was cooled to 0° C. and then treated with chlorotrimethylsilane (1557 mg, 14.33 mmol). It was warmed to rt and stirred for 2 h. Then, the reaction was cooled to 0° C. again, and isobutyric anhydride (486 mg, 3.07 mmol) was added dropwise. It was warmed to rt and stirred for 2 h. The reaction was quenched by the addition of methanol (5 mL). After 5 min, NH 4 OH (ca 29%, 10 mL) was added. The mixture was stirred at rt for 30 min. Then, it was concentrated and purified by column chromatography on silica gel eluting with 10% to 20% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 354.1 [M+H] + .  1 H-NMR (300 MHz, CD 3 OD) δ: 8.40 (s, 1H), 5.83-5.82 (m, 1H), 4.62-4.59 (m, 1H), 3.89-3.80 (m, 2H), 3.79-3.74 (m, 1H), 2.73-2.64 (m, 1H), 2.19-2.11 (m, 2H), 1.20 (d, J=6.8 Hz, 6H). 
     Step 11: N-(9-((2R,3R,5S)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     N-(9-((2R,3R,5 S)-3-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (510 mg, 1.443 mmol) was co-evaporated with pyridine (3×5 mL) and then re-suspended in pyridine (7 mL). To the suspension was added 4,4′-(chloro(phenyl)methylene)bis(methoxybenzene) (538 mg, 1.587 mmol), and the mixture was stirred at rt for 2 h. At that time the mixture was concentrated under reduced pressure, and the residue was purified by column chromatography on silica gel eluting with 1% to 4% MeOH in CH 2 Cl 2  (containing 1% Et 3 N) to give the product. LCMS (ES, m/z): 656.0 [M+H] + .  1 H-NMR (400 MHz, CD 3 OD) δ: 8.02 (s, 1H), 7.51-7.43 (m, 2H), 7.40-7.17 (m, 7H), 6.91-6.82 (m, 4H), 5.85-5.84 (d, J=2.3 Hz, 1H), 4.59-4.57 (m, 1H), 4.02-3.95 (m, 1H), 3.78 (s, 6H), 3.52-3.34 (m, 3H), 2.72-2.68 (m, 1H), 1.95-191 (m, 1H), 1.38 (d, J=6.8 Hz, 6H). 
     Preparation 19: N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-4-fluoro-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: ((2R,3R,4S)-4-(benzoyloxy)-3-fluoro-5-hydroxytetrahydrofuran-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of ((2R,3R,4S)-5-acetoxy-4-(benzoyloxy)-3-fluorotetrahydrofuran-2-yl)methyl benzoate (20.0 g, 49.7 mmol) in dry 1,2-dichloroethane (200 mL) was added tri-N-butyltin methoxide (28.8 mL, 99 mmol). The resulting mixture was stirred at 80° C. for 3 h and then concentrated in vacuo. The residue was diluted in 500 mL of ethyl acetate and washed with sat aq. NH 4 Cl (500 mL) and brine (500 mL). The separated organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-40% EtOAc/Hexane. LCMS (ES, m/z): 343.2 [M+H-H 2 O] + .  1 H NMR (500 MHz, Chloroform-d) δ 8.18-8.00 (m, 7H), 7.68-7.57 (m, 3H), 7.61-7.35 (m, 7H), 5.73 (dd, J=8.3, 4.6 Hz, 1H), 5.65 (dt, J=3.9, 2.0 Hz, 1H), 5.54 (t, J=4.7 Hz, 0H), 5.50-5.40 (m, 2H), 5.36-5.24 (m, 1H), 4.87 (dtd, J=25.5, 4.0, 1.5 Hz, 1H), 4.74-4.46 (m, 4H), 4.15 (q, J=7.2 Hz, 1H), 3.39 (d, J=4.1 Hz, 1H), 3.30 (dd, J=8.6, 3.4 Hz, 1H), 2.07 (s, 2H), 1.41-1.23 (m, 3H). 
     Step 2. (2R,3R,4S)-3-fluoro-2-hydroxy-5-(methoxyimino)pentane-1,4-diyl dibenzoate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of ((2R,3R,4S)-4-(benzoyloxy)-3-fluoro-5-hydroxytetrahydrofuran-2-yl)methyl benzoate (17.9 g, 49.7 mmol) in dry MeOH (100 mL) was added O-methylhydroxylamine hydrochloride (6.23 g, 74.6 mmol), followed by triethylamine (10.39 mL, 74.6 mmol). The reaction mixture was stirred at rt for 2 h and then concentrated in vacuo. The residue was diluted in 500 mL of ethyl acetate and washed with sat aq. NH 4 Cl (500 mL) and brine (500 mL). The organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was used for the next step directly without further purification. LCMS (ES, m/z): 390.2 [M+H] + . 
     Step 3: (2R,3S,4S)-3-fluoro-5-(methoxyimino)-2-(((4-nitrophenyl)sulfonyl)oxy)pentane-1,4-diyl dibenzoate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (2R,3R,4S)-3-fluoro-2-hydroxy-5-(methoxyimino)pentane-1,4-diyl dibenzoate (19.4 g, 49.7 mmol) in dry EtOAc (100 mL) was added 4-nitrobenzenesulfonyl chloride (16.5 g, 74.6 mmol), followed by triethylamine (10.4 mL, 74.6 mmol). The reaction mixture was stirred at rt for 18 h and was then diluted with 200 mL of ethyl acetate, washed with water (300 mL) and brine (300 mL). The separated organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-30% EtOAc/Hexane. LCMS (ES, m/z): 575.3 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 8.25-7.99 (m, 7H), 7.94-7.80 (m, 2H), 7.68-7.55 (m, 2H), 7.57-7.46 (m, 3H), 7.50-7.38 (m, 3H), 6.55 (ddd, J=17.2, 5.3, 2.8 Hz, 0H), 5.89 (ddd, J=17.7, 6.2, 4.1 Hz, 1H), 5.46-5.37 (m, 1H), 5.40-5.28 (m, 1H), 5.21 (t, J=4.3 Hz, 0H), 4.84 (tdd, J=12.8, 2.6, 1.5 Hz, 1H), 4.53 (dddd, J=23.1, 13.0, 7.0, 1.8 Hz, 1H), 4.14 (q, J=7.2 Hz, 1H), 3.99 (d, J=36.3 Hz, 4H), 2.06 (s, 2H), 1.44-1.23 (m, 2H). 
     Step 4. (2S,3S,4S)-2-bromo-3-fluoro-5-(methoxyimino)pentane-1,4-diyl dibenzoate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (2R,3 S,4S)-3-fluoro-5-(methoxyimino)-2-(((4-nitrophenyl)sulfonyl)oxy)pentane-1,4-diyl dibenzoate (21.3 g, 37.1 mmol) in dry DMF (100 mL) was added freshly opened lithium bromide powder (16.1 g, 185 mmol). The resulting mixture was stirred at 60° C. for 18 h. The reaction mixture was diluted in 300 mL of ethyl acetate and washed with water (500 mL) and brine (500 mL). The separated organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-25% EtOAc/Hexane to give product. LCMS (ES, m/z): 452.1 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 8.15-8.03 (m, 11H), 7.69-7.56 (m, 8H), 7.56-7.41 (m, 12H), 6.93-6.86 (m, 1H), 6.45 (ddd, J=14.7, 5.9, 4.7 Hz, 0H), 5.93 (ddd, J=11.8, 6.7, 5.9 Hz, 2H), 5.32 (s, 1H), 5.29-5.10 (m, 3H), 4.89-4.77 (m, 3H), 4.80-4.67 (m, 3H), 4.60-4.40 (m, 3H), 3.95 (d, J=16.9 Hz, 2H), 3.89 (s, 6H), 1.32-1.22 (m, 1H). 
     Step 5. (2S,3S,4S)-2-bromo-3-fluoro-5-oxopentane-1,4-diyl dibenzoate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (2S,3S,4S)-2-bromo-3-fluoro-5-(methoxyimino)pentane-1,4-diyl dibenzoate (20.0 g, 44.2 mmol) in THF (200 mL) was added 37% aqueous solution of formaldehyde (32.9 mL, 442 mmol) and 1N HCl (44.2 mL, 44.2 mmol). The resulting mixture was stirred at 55° C. for 5 h. The reaction mixture was concentrated in vacuo to remove most of the THF. The residue was diluted in 300 mL of ethyl acetate and washed with water (300 mL) and brine (300 mL). The separated organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was used for the next step without further purification. LCMS (ES, m/z): 423.2 [M+H] + . 
     Step 6: ((2R,3S,4R)-4-(benzoyloxy)-3-fluoro-5-hydroxytetrahydrothiophen-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (2S,3S,4S)-2-bromo-3-fluoro-5-oxopentane-1,4-diyl dibenzoate (18.7 g, 44.2 mmol) in NMP (150 mL) at 0° C. was added sodium hydrosulfide (5.0 g, 89.0 mmol). The resulting mixture was stirred at 0° C. for 30 min and then at rt for 30 min. The reaction mixture was diluted in 300 mL of ethyl acetate and washed with water (300 mL) and brine (300 mL). The organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was used for the next step without further purification. LCMS (ES, m/z): 359.2 [M+H—H 2 O] + . 
     Step 6: ((2R,3S,4R)-5-acetoxy-4-(benzoyloxy)-3-fluorotetrahydrothiophen-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of ((2R,3 S,4R)-4-(benzoyloxy)-3-fluoro-5-hydroxytetrahydrothiophen-2-yl)methyl benzoate (16.6 g, 44.2 mmol) in dry THF (150 mL) at 0° C. was added acetic anhydride (8.3 mL, 133 mmol) and trimethylamine (18.5 mL, 133 mmol). The resulting mixture was stirred at 0° C. for 30 min and then at rt for 2 h. The reaction was quenched by addition of MeOH, and the reaction mixture was concentrated in vacuo to remove most of the THF. The residue was diluted in 300 mL of ethyl acetate and washed with water (300 mL) and brine (300 mL). The separated organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-25% EtOAc/Hexane to give product. LCMS (ES, m/z): 441.2 [M+Na] + .  1 H NMR (500 MHz, Chloroform-d) δ 8.15-8.02 (m, 4H), 7.68-7.57 (m, 2H), 7.55-7.42 (m, 4H), 6.02 (t, J=2.4 Hz, 1H), 5.88 (ddd, J=6.1, 3.6, 2.4 Hz, 1H), 5.50-5.42 (m, 0H), 5.35 (dd, J=7.3, 3.6 Hz, 0H), 5.32 (s, 0H), 4.80-4.69 (m, 1H), 4.56 (dd, J=11.6, 5.9 Hz, 1H), 4.26-4.10 (m, 2H), 2.25-2.11 (m, 1H), 2.08 (d, J=10.0 Hz, 3H), 1.29 (t, J=7.1 Hz, 1H). 
     Step 7: ((2R,3S,4R,5R)-4-(benzoyloxy)-3-fluoro-5-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a suspension of N-(6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (15.86 g, 71.7 mmol) in ClCH 2 CH 2 Cl (300 mL) was added (Z)-trimethylsilyl N-(trimethylsilyl)acetimidate (35.1 mL, 143 mmol). The suspension was stirred at 70° C. overnight and was then cooled to −15° C. To this mixture was added ((2R,3S,4R)-5-acetoxy-4-(benzoyloxy)-3-fluorotetrahydrothiophen-2-yl)methyl benzoate (10 g, 23.90 mmol), followed by TMS-OTf (8.64 mL, 47.8 mmol). The reaction mixture was stirred at −15° C. for 2 h, then at rt for 5 h and finally at 70° C. for 5d. The reaction mixture was allowed to cool to RT and was then filtered. The filtrate was washed with sat. aq. NaHCO 3 , brine and then dried over Na 2 SO 4  and concentrated in vacuo. The residue was purified by silica gel column, eluting with 0-60% EtOAc/Hexane. Subsequent recrystallization from EtOAc gave product. LCMS (ES, m/z): 580.5 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 12.19 (s, 0H), 9.56 (s, 1H), 8.12-8.06 (m, 1H), 8.02-7.96 (m, 1H), 7.66 (s, 0H), 7.71-7.58 (m, 1H), 7.57-7.50 (m, 1H), 7.54-7.42 (m, 1H), 6.59 (ddd, J=25.3, 7.4, 3.1 Hz, 1H), 6.20 (d, J=7.4 Hz, 0H), 5.68-5.59 (m, 1H), 4.87 (ddd, J=11.7, 7.7, 1.5 Hz, 1H), 4.26-4.11 (m, 1H), 2.96 (hept, J=6.8 Hz, 1H), 1.38 (dd, J=19.0, 6.9 Hz, 3H). 
     Step 8: N-(9-((2R,3R,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,3 S,4R,5R)-4-(benzoyloxy)-3-fluoro-5-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-2-yl)methyl benzoate (0.96 g, 1.66 mmol) in THF (5 mL)/MeOH (4 mL)/H 2 O (1 mL) at 0° C. was added 2N sodium hydroxide (1.8 mL, 3.6 mmol). The reaction mixture was stirred at 0° C. for 30 min and then neutralized with acetic acid (0.38 mL, 6.6 mmol). The product was collected by filtration and carried on to the next step without further purification. LCMS (ES, m/z): 372.3 [M+H] + . 
     Step 9: N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(9-((2R,3R,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)-tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (0.62 g, 1.66 mmol) in pyridine (25 mL) at 0° C. was added 4,4′-dimethoxytrityl chloride (0.84 g, 2.48 mmol). The reaction mixture was stirred at 0° C. for 3 h. The reaction was quenched with H 2 O (1 mL), and the mixture was concentrated. The residue was diluted in 100 mL of ethyl acetate and washed with saturated aq. NaHCO 3  (100 mL) and brine (100 mL). The separated organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-100% EtOAc/Hexane containing 0.1% Et 3 N to give product. LCMS (ES, m/z): 674.6 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 11.96 (s, 0H), 8.35 (s, 0H), 7.70 (s, 0H), 7.63-7.56 (m, 1H), 7.50-7.43 (m, 2H), 7.38-7.24 (m, 1H), 6.93-6.85 (m, 2H), 5.92 (d, J=8.3 Hz, 0H), 5.35-5.23 (m, 1H), 4.15 (q, J=7.1 Hz, 1H), 3.85-3.69 (m, 3H), 3.46 (dd, J=10.2, 5.4 Hz, 0H), 3.35 (dd, J=10.2, 5.2 Hz, 0H), 2.09 (d, J=19.4 Hz, 2H), 1.34-1.22 (m, 2H), 1.01 (d, J=6.8 Hz, 1H), 0.91 (d, J=6.9 Hz, 1H). 
     Preparation 20: N-(3-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-4-fluoro-3-hydroxytetrahydrothiophen-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: N-(7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a suspension of 5-amino-3,6-dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7-one (5.0 g, 32.9 mmol) in anhydrous DMF (60 mL) was added isobutyric anhydride (12.5 mL, 76.0 mmol) dropwise. The reaction mixture was refluxed at 150° C. for 1 h. The reaction was quenched with MeOH (6.6 mL, 164 mmol) and concentrated in vacuo. The residue was taken up in DCM (50 mL)/Hexane (100 mL) and was stirred at vigorously at rt for 15 min. The product was collected by filtration. LCMS (ES, m/z): 223.2 [M+H] + .  1 H NMR (500 MHz, DMSO-d 6 ) δ 16.04 (s, 1H), 12.19 (s, 1H), 11.78 (s, 1H), 2.78 (hept, J=6.7 Hz, 1H), 1.13 (d, J=6.8 Hz, 6H). 
     Step 2: ((2R,3S,4R,5R)-4-(benzoyloxy)-3-fluoro-5-(5-isobutyramido-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)tetrahydrothiophen-2-yl)methyl benzoate 
     
       
         
         
             
             
         
       
     
     To a mixture of ((2R,3 S,4R)-5-acetoxy-4-(benzoyloxy)-3-fluorotetrahydrothiophen-2-yl)methyl benzoate (1.5 g, 3.6 mmol) and N-(7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide (0.96 g, 4.3 mmol) in nitromethane (20 mL) was added BF 3 *Et 2 O (0.54 mL, 4.3 mmol) and the resulting mixture was heated at 100° C. under microwave irradiation for 1 h. The reaction mixture was cooled, diluted in 100 mL of ethyl acetate and washed with saturated aq. NaHCO 3  (100 mL) and brine (100 mL). The organic portion was dried over Na 2 SO 4  and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-35% EtOAc/Hexane. LCMS (ES, m/z): 581.4 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 12.27 (s, 2H), 9.73 (s, 2H), 8.19-7.93 (m, 8H), 7.86-7.80 (m, 0H), 7.71-7.55 (m, 4H), 7.57-7.39 (m, 8H), 7.40-7.33 (m, 0H), 6.76 (d, J=6.7 Hz, 2H), 6.62-6.48 (m, 2H), 5.79 (t, J=2.9 Hz, 1H), 5.69 (t, J=2.9 Hz, 1H), 5.62-5.54 (m, 2H), 4.89 (ddd, J=11.6, 7.8, 1.3 Hz, 2H), 4.78-4.65 (m, 1H), 4.31-4.18 (m, 2H), 4.15 (q, J=7.1 Hz, 3H), 2.95 (hept, J=6.9 Hz, 2H), 2.81-2.68 (m, 1H), 2.07 (s, 4H), 1.39 (dd, J=17.5, 6.9 Hz, 10H), 1.34-1.24 (m, 8H). 
     Step 3: N-(3-((2R,3R,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of ((2R,3 S,4R,5R)-4-(benzoyloxy)-3-fluoro-5-(5-isobutyramido-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)tetrahydrothiophen-2-yl)methyl benzoate (4.5 g, 7.8 mmol) in THF (35 mL)/MeOH (28 mL)/H (7 mL) at 0° C. was added 2N sodium hydroxide (8.6 mL, 17.2 mmol). The reaction mixture was stirred at 0° C. for 1 h and then neutralized with acetic acid (2.3 mL, 39.0 mmol). Product was collected by filtration and carried on to the next step without further purification. LCMS (ES, m/z): 373.3 [M+H] + . 
     Step 4: N-(3-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-3-hydroxytetrahydrothiophen-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(3-((2R,3R,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl)-tetrahydrothiophen-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide (1.8 g, 4.8 mmol) in pyridine (30 mL) at 0° C. was added 4,4′-dimethoxytrityl chloride (1.8 g, 5.3 mmol). The reaction mixture was stirred at 0° C. for 1 h. The reaction was quenched with H 2 O (1 mL), and the mixture was concentrated. The residue was diluted in 100 mL of ethyl acetate and washed with saturated aq. NaHCO 3  (100 mL) and brine (100 mL). The separated organic layer was dried over anhydrous Na 2 SO 4 , filtered, and concentrated in vacuo. The residue was purified by a silica gel column, eluting with 0-100% EtOAc/Hexane containing 0.1% Et 3 N to give product. LCMS (ES, m/z): 675.5 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 12.16 (s, 1H), 8.48 (s, 0H), 7.57-7.50 (m, 1H), 7.49-7.37 (m, 2H), 7.39-7.29 (m, 0H), 7.31 (s, 1H), 7.32-7.14 (m, 1H), 6.91-6.81 (m, 2H), 6.22-6.16 (m, 0H), 5.42-5.31 (m, 1H), 3.77 (d, J=36.0 Hz, 7H), 3.46 (dd, J=10.2, 5.6 Hz, 0H), 3.36 (dd, J=10.2, 5.4 Hz, 0H), 2.17 (p, J=6.9 Hz, 0H), 1.06 (dd, J=26.1, 6.9 Hz, 3H). 
     Preparation 21: N-(3-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-3,4-dihydroxytetrahydrothiophen-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3S,4R,5R)-2-((benzoyloxy)methyl)-5-(5-isobutyramido-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)tetrahydrothiophene-3,4-diyl dibenzoate 
     
       
         
         
             
             
         
       
     
     BF 3 .OEt 2  (3.65 mL, 28.8 mmol) was added dropwise to a mixture of (2R,3R,4S,5R)-2-acetoxy-5-((benzoyloxy)methyl)tetrahydrothiophene-3,4-diyl dibenzoate (10.0 g, 19.2 mmol) and N-(7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5 yl)isobutyramide (5.98 g, 26.9 mmol) in MeNO 2  (180 mL) at ambient temperature. Upon completion of addition, the mixture was heated at 120° C. in a microwave reactor for 45 min. The sample was cooled to rt and concentrated in vacuo. The residue was purified by flash column chromatography eluting with EtOAc/isohexane (10-90%) to give desired product. LCMS (ES, m/z): 683.5 [M+H] + .  1 H NMR (500 MHz, Chloroform-d) δ 12.24 (s, 1H), 9.77 (s, 1H), 8.08-7.95 (m, 4H), 7.94-7.87 (m, 2H), 7.70-7.35 (m, 9H), 6.84 (d, J=5.9 Hz, 1H), 6.67 (dd, J=5.9, 3.9 Hz, 1H), 6.49 (t, J=3.7 Hz, 1H), 5.52 (dd, J=11.4, 7.8 Hz, 1H), 5.04 (dd, J=11.4, 7.8 Hz, 1H), 4.28 (m, 1H), 2.97 (hept, J=6.9 Hz, 1H), 1.42 (dd, 6.9 Hz, 6H). 
     Step 2: N-(3-((2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a stirred solution of the product from Step 1 (5.3 g, 7.8 mmol) dissolved in Pyridine (8 mL) and MeOH (32 mL) at 25° C. was added sodium hydroxide (1.24 g, 31.1 mmol) in one portion. The mixture was stirred at 25° C. for 15 min before the addition of acetic acid (1.8 mL, 31.1 mmol). The mixture was concentrated in vacuo, and the residue was purified by flash column chromatography eluting with EtOAc/isohexane (70-100%) to give the desired product. LCMS (ES, m/z): 371.3 [M+H] + .  1 H NMR (500 MHz, DMSO-d 6 ) δ 12.24 (s, 1H), 11.96 (s, 1H), 5.91 (d, J=5.6 Hz, 1H), 5.73 (d, J=5.5 Hz, 1H), 5.43 (d, J=5.0 Hz, 1H), 5.12 (m, 1H), 4.81 (m, br, 1H), 4.40 (m, 1H), 3.89-3.77 (m, 1H), 3.53 (m, 1H), 3.46-3.36 (m, 1H), 2.79 (m, 1H), 1.14 (dd, J=6.7, 1.2 Hz, 6H). 
     Step 3: N-(3-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3,4-dihydroxytetrahydrothiophen-2-yl)-7-oxo-6,7-dihydro-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To the product from step 2 (2.3 g, 6.2 mmol) was added pyridine (62 mL) at ambient temperature. To this mixture was added DMTrCl (2.3 g, 6.8 mmol). After 1 h, water (2 mL) was added, and it was concentrated in vacuo. Ethyl acetate (15 mL), water (5 mL) and brine (1 mL) were added. Layers were separated, and the aqueous layer was extracted with ethyl acetate twice (20 mL×2). The combined organics were dried over MgSO 4 , concentrated in vacuo and purified by flash column chromatography, eluting with 0 to 80% EtOAc in Hexane to give the desired product. LCMS (ES, m/z): 673.4 [M+H] +  0.1H NMR (500 MHz, DMSO-d 6 ) δ 12.24 (s, 1H), 11.96 (s, 1H), 7.50-7.36 (m, 2H), 7.35-7.10 (m, 9H), 6.96-6.82 (m, 4H), 5.88 (d, J=4.1 Hz, 1H), 5.83 (d, J=5.1 Hz, 1H), 5.42 (d, J=5.7 Hz, 1H), 4.66 (q, J=4.1 Hz, 1H), 4.45 (td, J=5.9, 3.5 Hz, 1H), 3.81-3.69 (6H), 3.65 (ddd, J=8.4, 6.0, 4.3 Hz, 1H), 3.46-3.35 (m, 1H), 3.19 (dd, J=9.4, 7.9 Hz, 1H), 2.78 (h, J=6.8 Hz, 1H), 1.22-1.05 (m, 6H). 
     Preparation 22: ammonium (2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     Step 1: N-(9-((2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     2-amino-9-((2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)tetrahydrothiophen-2-yl)-1,9-dihydro-6H-purin-6-one (1.7 g, 5.7 mmol) was co-evaporated with pyridine (3×5 mL) and then, re-dissolved in pyridine (34 mL). To the mixture at 0° C. was added chlorotrimethylsilane (4.32 g, 39.8 mmol) dropwise. It was stirred at rt for 1 h and then, cooled to 0° C. again. Isobutyric anhydride (1.348 g, 8.52 mmol) was added dropwise, and it was stirred at rt for 3 h. It was quenched by the addition of water (8.5 mL). After 5 min, NH 4 OH (ca. 29%, 17 mL) was added, and the mixture was stirred for 30 min. It was concentrated and purified by column chromatography eluted with 1 to 30% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 396.9 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 9.52 (br s, 2H), 8.39 (s, 1H), 5.79 (d, J=7.1 Hz, 1H), 5.59 (s, 1H), 5.40 (s, 1H), 5.22 (s, 1H), 4.55 (d, J=6.7 Hz, 1H), 4.21 (s, 1H), 3.77 (t, J=9.3 Hz, 1H), 3.61 (s, 1H), 3.30 (dt, J=6.4, 3.3 Hz, 1H), 2.78 (p, J=6.9 Hz, 1H), 1.13 (d, J=6.8 Hz, 6H). 
     Step 2: N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3,4-dihydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a mixture of N-(9-((2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)-tetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (480 mg, 1.299 mmol) in pyridine (10 mL) was added 4,4′-(chloro(phenyl)methylene)-bis(methoxybenzene) (484 mg, 1.43 mmol). It was stirred at rt for 16 h and then, concentrated. The crude was purified by column chromatography on silica gel eluted with 1 to 30% MeOH in CH 2 Cl 2  (containing 1% Et 3 N) to give the product. LCMS (ES, m/z): 672.2 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 +D 2 O): δ 8.08 (s, 1H), 7.39 (d, J=7.2 Hz, 2H), 7.32 (t, J=7.6 Hz, 2H), 7.26 (dt, J=9.1, 3.3 Hz, 5H), 6.94-6.87 (m, 4H), 5.75 (d, J=5.9 Hz, 1H), 4.39 (dd, J=5.9, 3.5 Hz, 1H), 4.14 (t, J=3.9 Hz, 1H), 3.74 (s, 6H), 3.49-3.37 (m, 2H), 3.33 (dd, J=14.5, 7.3 Hz, 1H), 2.87-2.67 (m, 1H), 1.11 (dd, J=6.8, 1.6 Hz, 6H). 
     Step 3: N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide and N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-((tert-butyldimethylsilyl)oxy)-4-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-3,4-dihydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (580 mg, 0.863 mmol) in DMF (5 mL) at rt was added 1H-imidazole (147 mg, 2.16 mmol) and tert-butylchlorodimethylsilane (156 mg, 1.04 mmol). After 6 h, the mixture was diluted with EtOAc (50 mL) and washed with sat aq NaHCO 3  (2×20 mL) and brine (20 mL). It was dried (Na 2 SO 4 ), concentrated, and purified by reverse phase (C18) chromatography eluted with 0 to 95% ACN in water to give the products. LCMS (ES, m/z): 786.3 [M+H] + . 
     Step 4. (2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phenyl phosphonate and (2R,3S,4R,5R)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-5-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phenyl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of a mixture of N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)-methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-3-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide and N-(9-((2R,3R,4S,5R)-5-((bis(4-methoxyphenyl) (phenyl)methoxy)methyl)-3-((tert-butyldimethylsilyl)oxy)-4-hydroxytetrahydrothiophen-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (220 mg, 0.280 mmol) in pyridine (2 mL) at 0° C. was added diphenyl phosphonate (98 mg, 0.420 mmol). The resulting mixture was stirred at rt for 20 min. It was used in the next reaction step without purification. LCMS (ES, m/z): 926.2 [M+H] + . 
     Step 5. ammonium (2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from Step 4 at 0° C. was added Et 3 N (0.28 mL, 2.0 mmol) and water (0.28 mL). It was stirred at rt for 30 min. It was concentrated, and the residue was partitioned between CH 2 Cl 2  (40 mL) and aq NaHCO 3  (5%, 30 mL). The organic layer was washed with aq NaHCO 3  (5%, 2×30 mL), dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography using 0-10% MeOH in CHCl 3  containing 1% Et 3 N to give a mixture. The mixture was further purified by prep-HPLC Prep-HPLC (XBridge Shield RP18 OBD Column, 19×150 mm) eluted with 46 to 79% ACN in aq NH 4 HCO 3  (10 mM) over 7 min to give the product. LCMS (ES, m/z): 850.2 [M+H] + .  1 H-NMR (400 MHz, CD 3 OD): δ 8.18 (s, 1H), 7.68 (s, 0.5H), 7.59-7.49 (m, 2H), 7.45-7.36 (m, 4H), 7.37-7.30 (m, 2H), 7.28-7.22 (m, 1H), 6.95-6.87 (m, 4H), 6.16-6.07 (m, 2H), 4.88-4.87 (m, 1H), 4.69 (dd, J=7.3, 3.3 Hz, 1H), 3.81 (s, 6H), 3.51 (dd, J=4.9, 1.9 Hz, 2H), 3.37 (s, 1H), 2.67 (p, J=6.9 Hz, 1H), 1.21 (dd, J=6.9, 0.9 Hz, 6H), 0.77 (s, 9H), 0.01 (s, 3H), −0.28 (s, 3H).  31 P-NMR (162 MHz, DMSO-d 6 ): δ −0.74 (s, 1P). 
     Preparation 23: 2-amino-9-[5-O-(hydroxy{[hydroxy(phosphonooxy)phosphoryl]oxy}-phosphoryl)-β-D-xylofuranosyl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     Step 1: 2-amino-9-[5-O-(hydroxy{[hydroxy(phosphonooxy)phosphoryl]foxy}-phosphoryl)-β-D-xylofuranosyl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To a stirred solution of 9-(2,3-di-O-acetyl-β-D-xylofuranosyl)-2-[(2-methylpropanoyl)-amino]-1,9-dihydro-6H-purin-6-one (100 mg, 0.229 mmol) in pyridine (0.25 mL) and 1,4-dioxane (0.75 mL) was added a freshly prepared solution of 2-chloro-4H-1,3,2-benzodioxaphosphorin-4-one (50 mg, 0.247 mmol) in 1,4-dioxane (0.25 mL). The reaction mixture was stirred at ambient temperature for 10 min, and then a solution of tributylammonium pyrophosphate (189 mg, 0.344 mmol) in DMF (0.69 mL) was added, followed by addition of tributylamine (0.23 mL, 0.968 mmol) in one portion at ambient temperature. The reaction mixture was stirred for 10 min at ambient temperature, and then a solution of iodine (29.0 mg, 0.114 mmol) in pyridine (0.50 mL) and water (0.05 mL) was added. The reaction mixture was stirred for 15 min, excess iodine was quenched with 5% aq NaHSO 3  (3 mL), and the reaction mixture was evaporated to dryness. The residue was dissolved in 10 mL H 2 O, and after standing at rt for 30 min, 28% aq ammonium hydroxide (5 mL) was added. The reaction mixture was stirred at 50° C. for 5 h. LCMS indicated full conversion to desired product, and the mixture was filtered and lyophilyzed. The product was purified using mass-directed reverse phase HPLC with a Waters SunFire C18 OBD Prep Column, 100 Å, 5 μm, 19 mm×150 mm, [Waters Part #186002568] using a gradient solvent system with MeCN and 100 mM aq triethylammonium acetate. Lyophilization of the product fractions furnished 2-amino-9-[5-O-(hydroxy{[hydroxy(phosphonooxy)phosphoryl]oxy}phosphoryl)-3-D-xylofuranosyl]-1,9-dihydro-6H-purin-6-one as the tetra-triethylamine salt. LCMS (ES, m/z): 522 [M−H] − . 
     Preparation 24: ((2R,3S,4R,5S)-5-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl tetrahydrogen triphosphate 
     
       
         
         
             
             
         
       
     
     Step 1. ((3aR,4R,6S,6aS)-6-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-2-methoxytetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methanol 
     
       
         
         
             
             
         
       
     
     To the stirred suspension of (2S,3R,4S,5R)-2-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol (30 mg, 0.105 mmol) in 1,4-dioxane (0.3 mL) was added trimethyl orthoformate (0.22 mL, 2.011 mmol) in one portion at ambient temperature, followed by p-toluenesulfonic acid monohydrate (22 mg, 0.116 mmol). The reaction mixture was stirred at ambient temperature for 16 h. LCMS indicated significant conversion to desired product, and the crude mixture was carefully quenched by adding triethylamine (0.05 mL) at 0° C. Following concentration, the residue was purified by flash column chromatography on 12 gram silica gel using a gradient solvent system with MeOH and CH 2 Cl 2 . Concentration of the product fractions furnished ((3aR,4R,6S,6aS)-6-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-2-methoxytetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methanol. LCMS (ES, m/z): 310 [M+H] + . 
     Step 2: ((3aR,4R,6S,6aS)-6-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-2-methoxytetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methyl tetrahydrogen triphosphate 
     
       
         
         
             
             
         
       
     
     To the stirred suspension of ((3aR,4R,6S,6aS)-6-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-2-methoxytetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methanol (16 mg, 0.052 mmol) in pyridine (0.05 mL) and 1,4-dioxane (0.15 mL) was added DMF (0.05 mL) to form a homogeneous solution. To this solution was added a freshly prepared solution of 2-chloro-4H-1,3,2-benzodioxaphosphorin-4-one (12 mg, 0.059 mmol) in 1,4-dioxane (0.05 mL) at ambient temperature. The reaction mixture was stirred at ambient temperature for 15 min, and then a solution of tributylammonium pyrophosphate (43 mg, 0.078 mmol) in DMF (0.10 mL) was added, followed by tributylamine (0.052 mL, 0.219 mmol). The reaction mixture was stirred at ambient temperature for 15 min, and then a solution of iodine (6.58 mg, 0.026 mmol) in pyridine (0.10 mL) and water (0.01 mL) was added. The reaction mixture was stirred at ambient temperature for 15 min and excess iodine was quenched with 5% aqueous NaHSO 3  (0.5 mL). LCMS indicated significant conversion to desired product, and the reaction mixture was concentrated to yield ((3 aR,4R,6S,6aS)-6-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-2-methoxytetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methyl tetrahydrogen triphosphate, which was used directly in the next reaction step without additional purification. LCMS (ES, m/z): 548 [M−H] − . 
     Step 3. ((2R,3S,4R,5S)-5-(7-amino-H-pyrazolo[4,3-d]pyrimidin-3-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl tetrahydrogen triphosphate 
     
       
         
         
             
             
         
       
     
     To the stirred solution of crude ((3aR,4R,6S,6aS)-6-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-2-methoxytetrahydrofuro[3,4-d][1,3]dioxol-4-yl)methyl tetrahydrogen triphosphate (49.4 mg, 0.090 mmol) in water (0.15 mL) and DMF (0.15 mL) was added formic acid (0.4 mL, 10.60 mmol) in one portion. The reaction mixture was stirred at ambient temperature for 18 h. LCMS indicated significant conversion to desired product, and the mixture was filtered and lyophilyzed. The product was purified using mass-directed reverse phase HPLC with a Waters SunFire C18 OBD Prep Column, 100 Å, 5 m, 19 mm×150 mm, [Waters Part #186002568] using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate. Lyophilization of the product fractions furnished ((2R,3 S,4R,5 S)-5-(7-amino-1H-pyrazolo[4,3-d]pyrimidin-3-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl tetrahydrogen triphosphate. LCMS (ES, m/z): 506 [M−H] − . 
     Preparation 25: ((2R,3S,4R,5R)-5-(6-amino-2-fluoro-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl tetrahydrogen triphosphate 
     
       
         
         
             
             
         
       
     
     Step 1: ((2R,3S,4R,5R)-5-(6-amino-2-fluoro-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl tetrahydrogen triphosphate 
     
       
         
         
             
             
         
       
     
     To a mixture of 2-fluoroadenosine (200 mg, 0.701 mmol) in trimethylphosphate (1.948 mL, 16.83 mmol) was added tributylamine (0.500 mL, 2.104 mmol), and the mixture was stirred 15 min at rt and then cooled in an ice/brine bath. Then POCl 3  (0.137 mL, 1.472 mmol) was added dropwise with bath temperature maintained at −5 to 0° C. After 1.25 h, a 0° C. mixture of tributylammonium pyrophosphate (327 mg, 0.596 mmol), MeCN (2.8 mL) and tributylamine (1.000 mL, 4.21 mmol) were added, and the mixture was allowed to warm to rt, followed by 16 h stirring at rt. The mixture was purified directly by reverse phase HPLC using a gradient of 1-20% MeCN with 100 mM aqueous triethylammonium acetate to furnish ((2R,3 S,4R,5R)-5-(6-amino-2-fluoro-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl tetrahydrogen triphosphate mg. LCMS (ES, m/z): 524 [M−H] − . 
     Preparation 26: 3′-(aminomethyl)-3′-deoxyguanosine 5′-(tetrahydrogen triphosphate) 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures (WO2015161137). 
     The Preparations below were used as shown or were further modified through additional synthetic manipulations analogous to those described in Preparations 1-26. 
     Preparation 27: 2-amino-9-((β-D-xylofuranosyl)-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Journal of Medicinal Chemistry  1987, 30(6), 982-991). 
     Preparation 28: 5-amino-3-((β-D-ribofuranosyl)-3,6-dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Journal of Organic Chemistry  2007, 72(1), 173-179). 
     Preparation 29: 9-{3-azido-5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-3-deoxy-β-D-ribofuranosyl}-N-(phenylcarbonyl)-9H-purin-6-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Bulletin of the Korean Chemical Society  2004, 25(2), 243-248 and  Nucleosides, Nucleotides  &amp;  Nucleic Acids  2005 24(10-12), 1707-1727). 
     Preparation 30: 1-(β-D-ribofuranosyl)-1H-imidazo[4,5-c]pyridin-4-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Tetrahedron  1993, 49(3), 557-570). 
     Preparation 31: 1-(β-D-ribofuranosyl)-1,5-dihydro-4H-imidazo[4,5-c]pyridin-4-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Tetrahedron  1993, 49(3), 557-570) 
     Preparation 32: 4′-thioadenosine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Journal of Medicinal Chemistry  2006, 49(5), 1624-1634). 
     Preparation 33: 7-((β-D-ribofuranosyl)-3,7-dihydro-4H-imidazo[4,5-d][1,2,3]triazin-4-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Organic  &amp;  Biomolecular Chemistry  2014, 12(23), 3813-3815). 
     Preparation 34: 3-β-D-ribofuranosyl)-3H-imidazo[4,5-b]pyridin-7-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Biochemistry  2005, 44(37), 12445-12453). 
     Preparation 35: 7-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Journal of the Chemical Society, Perkin Transactions  1 : Organic and Bio - Organic Chemistry  1995 (12), 1543-50). 
     Preparation 36: 1-(3-deoxy-β-D-erythro-pentofuranosyl)-1,5-dihydro-4H-imidazo[4,5-c]pyridin-4-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Chemical  &amp;  Pharmaceutical Bulletin  1996, 44(2), 288-295). 
     Preparation 37: 7-(2-deoxy-β-D-erythro-pentofuranosyl)-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-4-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Synthesis  2006 (12), 2005-2012). 
     Preparation 38: (2S,3R,4S,5R)-2-(4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures (WO2015148746). 
     Preparation 39: N-(8-((2R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-hydroxytetrahydrofuran-2-yl)pyrazolo[1,5-a][1,3,5]triazin-4-yl)benzamide 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures (WO2015148746). 
     Preparation 40: 7-(2-deoxy-4-ethynyl-β-D-erythro-pentofuranosyl)-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-4-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures (WO2015148746). 
     Preparation 41: 9-(2-chloro-2-deoxy-β-D-arabinofuranosyl)-9H-purin-6-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Journal of the American Chemical Society  1996, 118(46), 11341-11348). 
     Preparation 42: 2′-deoxy-2′-methyladenosine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Synthesis  2005 (17), 2865-2870). 
     Preparation 43: (2R,3R,4S,5R)-2-(6-amino-9H-purin-9-yl)-5-((R)-1-hydroxyethyl)tetrahydrofuran-3,4-diol 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Bioorganicheskaya Khimiya  1989, 15(7), 969-975). 
     Preparation 44: 5-fluoro-7-(β-D-ribofuranosyl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Nucleosides, Nucleotides , &amp;  Nucleic Acids  2004, 23(1-2), 161-170). 
     Preparation 45: 1-(β-D-ribofuranosyl)-1,5-dihydro-4H-imidazo[4,5-d]pyridazin-4-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Journal of the Chemical Society, Perkin Transactions  1 : Organic and Bio - Organic Chemistry  (1972-1999), 1989 (10), 1769-1774). 
     Preparation 46: 2-amino-9-[(2R,3R,4S,5S)-5-fluoro-3,4-dihydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures (WO2014099941) 
     Preparation 47: 2-amino-9-((2R,3R,5S)-3-hydroxy-5-(hydroxymethyl)-4-methylenetetrahydrofuran-2-yl)-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Journal of Medicinal Chemistry  1992, 35, 2283-2293). 
     Preparation 48: (2S,3R,4S,5R)-2-(4-aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol 
     
       
         
         
             
             
         
       
     
     The title compound was prepared according to published procedures ( Tetrahedron Letters  1994, 35(30), 5339). 
     The following experimental procedures detail the preparation of specific examples of the instant disclosure. The compounds of the examples are drawn in their neutral forms in the procedures and tables below. In some cases, the compounds were isolated as salts depending on the method used for their final purification and/or intrinsic molecular properties. The examples are for illustrative purposes only and are not intended to limit the scope of the instant disclosure in any way. 
     EXAMPLES 
     Example 1: (5R,7R,8R,12aR,14R,15aS,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-16-hydroxyoctahydro-12H-5,8-methanofuro[3,2-1][11,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl (2-cyanoethyl) phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (3 g, 3.09 mmol) in ACN (15 mL) was added water (0.111 mL, 6.18 mmol) and pyridin-1-ium 2,2,2-trifluoroacetate (0.717, 3.71 mmol). The resulting mixture was stirred at RT, and the reaction progress was monitored by LCMS/TLC. After the phosphoramidite was consumed, the reaction mixture containing the product was used in the next step without purification. LCMS (ES, m/z): 887.4 [M+H] + . 
     Step 2: 2-methylpropan-2-aminium (2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl) methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from Step 1 (assumed to contain 3.09 mmol of (2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-(tert-butyldimethylsilyloxy)-2-(2-isobutyramido-6-oxo-1,6-dihydropurin-9-yl)-tetrahydrofuran-3-yl 2-cyanoethyl phosphonate) was added tert-butylamine (15.0 mL, 142 mmol) in one portion, and the resulting solution was stirred at rt for 40 min. It was concentrated, and the residue was co-evaporated with ACN (2×15 mL) to give the product, which was used for the next step without further purification. LCMS (ES, m/z): 832.3 [M−H] − . 
     Step 3: pyridin-1-ium (2R,3R,4R,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of crude 2-methylpropan-2-aminium (2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (˜4.2 g, ˜3.09 mmol, from step 2) in CH 2 Cl 2  (37 mL) were added water (0.558 mL, 31.0 mmol) and dichloroacetic acid in CH 2 Cl 2  (6%, 37 mL, 31.5 mmol). It was stirred for 40 min. Then, triethylsilane (60 mL) was added, and the solution was stirred for 1.5 h. Pyridine (4.5 mL) was added to the reaction. It was concentrated. The residue was triturated with MTBE (50 ml) and Hexane (50 mL), and the supernatant was decanted. This process was repeated twice. The crude mixture was kept over P 2 O 5  under reduced pressure for 20 h to give a crude mixture containing the product. LCMS (ES, m/z): 532.2 [M+H] + . 
     Step 4. (2R,3R,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of pyridin-1-ium (2R,3R,4R,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (680 mg, crude, ˜0.722 mmol) in ACN (5 mL) under Ar was added activated 4 Å molecular sieves (100 mg). The resulting mixture was stirred at rt over 30 min. (2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl) tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (0.805 g, 0.939 mmol) was co-evaporated with ACN (3×1 mL), re-dissolved in ACN (5 mL), and dried by adding activated 4 Å molecular sieve (100 mg). After 30 min, it was added to the previously prepared mixture containing pyridin-1-ium (2R,3R,4R,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate. The mixture was stirred at rt for 1 h. The reaction mixture containing the product was used in the next reaction step immediately without purification. LCMS (ES, m/z): 1288.4 [M+H] + . 
     Step 5. (2R,3R,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphoryl) oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture containing the crude (2R,3R,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (˜1 mmol, with excess pyridinium 2,2-dichloroacetate) was added tert-butyl hydroperoxide in decane (5.5M, 0.64 mL, 3.5 mmol) dropwise. It was stirred at rt for 1 h. Then, the solution was cooled to 0° C., and NaHSO 3  (250 mg) in water (5 mL) was added slowly. After 5 min, the mixture was concentrated, and the residue was purified by reverse phase (C18) chromatography eluted with 5 to 45% ACN in aq NH 4 HCO 3  (0.04%) to give the product. LCMS (ES, m/z): 1305.6 [M+H] + . 
     Step 6. (2R,3R,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-(hydroxymethyl) tetrahydrofuran-3-yl) oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-((tert-butyldimethylsilyl) oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (2R,3R,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (340 mg, 0.239 mmol) in CH 2 Cl 2  (4 mL) were added water (44.5 mg, 2.468 mmol) and dichloroacetic acid (0.280 g, 2.17 mmol) in CH 2 Cl (5 ml). It was stirred at rt for 30 min. Et 3 SiH (4 mL) was then added, and the mixture was stirred for 1.5 h. Pyridine (3 mL) was added to the reaction, and it was concentrated to give a crude product, which was used for the next step without purification. LCMS (ES, m/z): 1002.4 [M+H] + . 
     Step 7: (5R,7R,8R,12aR,14R,15aS,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl) amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2-oxide 
     
       
         
         
             
             
         
       
     
     Crude (2R,3R,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (1.5 g, ˜0.24 mmol) was co-evaporated with pyridine (3×5 mL) and then re-dissolved in pyridine (4 mL). To the reaction was added 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphinane 2-oxide (160 mg, 0.865 mmol) in one portion. The resulting mixture was stirred at rt for 1 h. It was used for the next reaction step directly without purification. LCMS (ES, m/z): 984.3 [M+H] + . 
     Step 8. (5R,7R,8R,12aR,14R,15aS,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     To the stirred mixture containing (5R,7R,8R,12aR,14R,15aS,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2-oxide was added water (156 mg, 8.65 mmol) and iodine (81 mg, 0.321 mmol). After 10 min, the mixture was poured into a solution of NaHSO 3  (52 mg) in water (36 ml), and it was stirred for 5 min. It was cooled to 0° C., and NaHCO 3  (1.04 g) was slowly added. After 5 min, EtOAc (50 mL) and Et 2 O (50 ml) were added. Layers were separated, and the aq layer was extracted with EtOAc (1×30 ml). The organic layers were combined, concentrated, and purified by silica gel column chromatography eluted with 0-20% MeOH in CH 2 Cl 2  to give the product. LCMS (ES, m/z): 998.3 [M+H] + . 
     Step 9: (5R,7R,8R,12aR,14R,15aS,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino-9H-purin-9-yl}octahydro-12H-5,8-methanofuro 3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (5R,7R,8R,12aR,14R,15aS,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2,10-dioxide (160 mg) in ACN (2 mL) was added tert-butylamine (2 mL) at rt. After 30 min, it was concentrated to give the crude product, which was used for the next step without purification. LCMS (ES, m/z): 945.2 [M+H] + . 
     Step 10: (5R,7R,8R,12aR,14R,15aS,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-16-{[tert-butyl(dimethyl)silyl]oxy}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     Crude (5R,7R,8R,12aR,14R,15aS,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-dioxide (220 mg) was dissolved in a solution of MeNH 2  in EtOH (30%, 4 mL), and it was stirred at rt for 5 h. Then, the volatile component was removed under reduced pressure to give a crude product, which was used for the next reaction step without purification. LCMS (ES, m/z): 773.2 [M+H] +  and 771.3 [M−H] − . 
     Step 11: (5R,7R,8R,12aR,14R,15aS,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-16-hydroxyoctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     The crude from Step 10 was co-evaporated with pyridine (2.5 ml) and Et 3 N (2.5 mL) three times. It was dissolved in pyridine (2 mL). To the solution was added Et 3 N (1.51 g, 14.9 mmol) and triethylamine trihydrofluoride (1.2 g, 7.45 mmol) dropwise. The mixture was heated at 50° C. for 5 h. Then, it was concentrated and purified by preparative-HPLC (T3 Prep Column, 100 Å, 5 μm, 19 mm×250 mm) eluted with 0 to 10% ACN in aq NH 4 HCO 3  (50 mM) to give the product. LCMS (ES, m/z): 657.1 [M−H] − .  1 H-NMR: (300 MHz, DMSO-d 6 +D 2 O): δ 8.35 (s, 1H), 8.16 (s, 1H), 8.03 (s, 1H), 6.34 (dd, J=8.8, 5.9 Hz, 1H), 5.85 (d, J=8.3 Hz, 1H), 5.12-4.98 (m, 2H), 4.36 (d, J=3.9 Hz, 1H), 4.22 (t, J=7.2 Hz, 1H), 4.09 (s, 1H), 3.96-3.79 (m, 4H), 3.09-2.99 (m, 1H), 2.64-2.51 (m, 1H).  31 P-NMR: (121 MHz, DMSO-d 6 +D 2 O): δ −1.65 (s), −2.36 (s). 
     Examples 2 through 19, shown in Table 1 below, were prepared according to procedures analogous to those outlined in Example 1 above using the appropriate nucleoside monomers, described as Preparations or as obtained from commercial sources. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                  2 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15R,15aR,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6- amino-9H-purin-9-yl)-15-fluoro-16- hydroxyoctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10-diolate 2,10-dioxide 
                 675 
               
               
                   
               
               
                  3 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15aS,16R)-7,14-bis(6- amino-9H-purin-9-yl)-16-hydroxyoctahydro- 12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10-diolate 2,10-dioxide 
                 657 
               
               
                   
               
               
                  4 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15R,15aR,16R)-7,14-bis(6- amino-9H-purin-9-yl)-15-fluoro-16- hydroxyoctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10-diolate 2,10-dioxide 
                 659 
               
               
                   
               
               
                  5 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8S,12aR,14R,15R,15aS,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6- amino-9H-purin-9-yl)-16-fluoro-15- hydroxyoctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10-diolate 2,10-dioxide 
                 675 
               
               
                   
               
               
                  6 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15R,15aS,18R)-7-(2-amino- 6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino- 9H-purin-9-yl)-18-hydroxyhexahydro-14H- 15,12a-(epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10(12H)-diolate 2,10-dioxide 
                 685 
               
               
                   
               
               
                  7 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15S,15aR,16R)-7-(2-amino- 6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino- 9H-purin-9-yl)-15-fluoro-16-hydroxyoctahydro- 12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-dioxide 
                 675 
               
               
                   
               
               
                  8 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15aS,16R)-7-(2-amino-6- oxo-1,6-dihydro-9H-purin-9-yl)-16-hydroxy-14- (6-oxo-1,6-dihydro-9H-purin-9-yl)octahydro- 12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-dioxide 
                 660 [M + H] +   
               
               
                   
               
               
                  9 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15R,15aS,16R)-7-(2-amino- 6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(4-amino- 7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- dihydroxyoctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10-diolate 2,10-dioxide 
                 672 
               
               
                   
               
               
                 10 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15aS,16R)-7-(2-amino-6- oxo-1,6-dihydro-9H-purin-9-yl)-14-(4-amino- 7H-pyrrolo[2,3-d]pyrimidin-7-yl)-16- hydroxyoctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10-diolate 2,10-dioxide 
                 656 
               
               
                   
               
               
                 11 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15R,15aS,16S)-7-(2-amino- 6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino- 9H-purin-9-yl)-15,16-dihydroxyoctahydro-12H- 5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecine-2,10- diolate 2,10-dioxide 
                 689 
               
               
                   
               
               
                 12 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15R,15aS,16R)-7-(2-amino- 6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino- 9H-purin-9-yl)-12a-ethynyl-15,16- dihydroxyoctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine- 2,10-diolate 2,10-dioxide 
                 699 [M + H] +   
               
               
                   
               
               
                 13 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14-(6- amino-9H-purin-9-yl)-2,10,15-trihydroxy-16- methoxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 687 
               
               
                   
               
               
                 14 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5S,7R,8R,12aR,14R,15R,15aS,16R)-14-(6- amino-9H-purin-9-yl)-16-azido-2,10,15- trihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 698 
               
               
                   
               
               
                 15 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15-chloro-2,10,16- trihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 691 
               
               
                   
               
               
                 16 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5S,7R,8R,12R,12aR,14R,15R,15aS)-14-(6- amino-9H-purin-9-yl)-2,10,15-trihydroxy-12- methyl-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 671 
               
               
                   
               
               
                 17 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(2aR,5S,6aS,7R,8R,9aR,12S,14R,14aS,15R)-8- (6-amino-9H-purin-9-yl)-5,7,12-trihydroxy-5,12- dioxidohexahydro-6aH-2a,14- (epoxymethano)furo[3,2-d]oxeto[2,3- k][1,3,7,9,2,8]tetraoxadiphosphacyclotridecin- 15(2H,3H)-yl]-1,9-dihydro-6H-purin-6-one 
                 685 
               
               
                   
               
               
                 18 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12S,12aS,14R,15R,15aS)- 14-(6-amino-9H-purin-9-yl)-2,10,15-trihydroxy- 12-methyl-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 671 
               
               
                   
               
               
                 19 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dihydroxy-15- methyl-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 655 
               
               
                   
               
            
           
         
       
     
     Example 20: (5R,7R,8S,12aR,14R,15R,15aS,18R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-18-fluorohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10(12H-diolate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     Step 1. (2R,3514R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phenyl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of N-(9-((2R,3 S,4 S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy) methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (1 g, 1.520 mmol) in pyridine (7.6 mL) under Ar was added diphenyl phosphonate (1.068 g, 4.56 mmol), and it was stirred at rt for 20 min. The reaction mixture containing the product was used for the next reaction step without purification. 
     Step 2. (2R,3,4R,5R)-5-((bis(4-m ethoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from Step 1 was added water (1.5 ml) and Et 3 N (1.5 mL). The mixture was stirred at rt for 20 min. Then, it was concentrated, and the residue was partitioned between CH 2 Cl 2  (50 mL) and aq NaHCO 3  (5%, 20 mL). Layers were separated. The organic layer was washed with aq NaHCO 3  (5%, 2×20 mL), dried (Na 2 SO 4 ), concentrated and purified by silica gel column chromatography using 0 to 7% MeOH in CH 2 Cl 2  (1% Et 3 N) to give the product. LCMS (ES, m/z): 722 [M+H] + .  31 P-NMR: (162 MHz, CD 3 OD): δ 2.73 (s, 1P). 
     Step 3. (2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of the product of Step 2 (0.9 g, 0.999 mmol) in CH 2 Cl 2  (6 mL) were added water (0.180 g, 9.99 mmol) and 2,2-dichloroacetic acid (1.16 g, 8.99 mmol) in CH 2 Cl 2  (10 ml). The mixture was stirred at rt for 15 min. Et 3 SiH (10 mL) was added, and it was stirred for 1 h. Then, pyridine (2 mL) was added, and it was concentrated. The residue was purified by reverse phase (C18) chromatography eluted with 0 to 30% ACN in aq NH 4 HCO 3  (0.04%) to give the product. LCMS (ES, m/z): 722 [M−H] − . 417.9.  1 H-NMR: (400 MHz, CD 3 OD): δ 8.31 (s, 1H), 7.49 (d, J=1.6 Hz, 0.5H), 6.15 (d, J=6.8 Hz, 1H), 5.91 (d, J=1.6 Hz, 0.5H), 5.42-5.32 (m, 1.5H), 5.21 (dd, J=4.5, 1.9 Hz, 0.5H), 4.45-4.32 (m, 1H), 3.81 (d, J=3.5 Hz, 2H), 3.20 (q, J=7.4 Hz, 1H), 2.73 (p, J=6.9 Hz, 1H), 1.30 (t, J=7.3 Hz, 1.5H), 1.23 (d, J=6.9 Hz, 6H).  19 F-NMR: (376 MHz, CD 3 OD): δ −200.96 (s, 1F).  31 P-NMR: (162 MHz, CD 3 OD): δ 2.41 (s, 1P). 
     Step 4: (2R,3S,4R,5R)-5-((((((1R,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     (2R,3 S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (600 mg, 0.676 mmol) was co-evaporated with ACN (3×5 mL), re-dissolved in ACN (3 mL), dried by addition of activated 4 Å molecular sieves (150 mg) and kept under Ar. (1R,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl (2-cyanoethyl) diisopropylphosphoramidite (available from Exiqon (EQ-0063-1000), 235.5 mg, 0.56 mmol) and pyridinium 2,2,2-trifluoroacetate (162 mg, 0.84 mmol) were co-evaporated with ACN (3×5 mL), re-dissolved in ACN (5 mL), and dried by addition activated 4 Å molecular sieve (150 mg). After 30 min, it was added to the previously prepared mixture containing (2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate. The mixture was stirred at rt for 1 h. The reaction mixture containing the product was used in the next reaction step immediately without purification. LCMS (ES, m/z): 1202.3 [M−H] − . 
     Step 5. (2R,3S,4R,5R)-5-((((((R, 3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the stirred reaction mixture from Step 4 was added tert-butyl hydroperoxide in decane (5.5M, 0.31 mL, 1.71 mmol) dropwise. The resulting mixture was stirred at rt for 1 h. After 30 min, the solution was cooled to 0° C., and NaHSO 3  (150 mg) in water (5 mL) was added slowly. After 5 min, the mixture was concentrated, and the residue was purified by reverse phase (C18) chromatography eluted with 0 to 75% ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 1220.1 [M+H] + .  19 F-NMR (376 MHz, CD 3 OD): δ −200.38, −202.45 (2s, 1F).  31 P-NMR: (162 MHz, CD 3 OD): δ 2.57, 2.49 (2s, 1P); −3.52, −4.21 (2s, 1P). 
     Step 6. (2R,3S,4R,5R)-5-((((((S, 3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-(hydroxymethyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3S,4R,5R)-5-((((((1R,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (190 mg, 0.16 mmol) in CH 2 Cl 2  (2.5 mL) was added water (28.8 mg, 1.6 mmol) and dichloroacetic acid in CH 2 Cl 2  (0.6M, 2.5 mL). The mixture was stirred at rt for 10 min, and then Et 3 SiH (4.5 mL) was added. After 1 h, pyridine (0.5 mL) was added. After 10 min, the resulting mixture was concentrated to give the product, which was used for the next reaction step without purification. LCMS (ES, m/z): 917.9 [M+H] + .  31 P-NMR: (162 MHz, CD 3 OD): δ 2.51, 2.34 (2s, 1P); −3.46, −3.82 (2s, 1P). 
     Step 7: (5R,7R,8S,12aR,14R,15R,15aS,18R)-2-(2-cyanoethoxy)-18-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10 (12H)-olate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     To pyridine (16 mL) under Ar was added diphenyl chlorophosphate (0.66 mL, 3.2 mmol). It was cooled at −40° C. and then, a solution of crude from Step 6 in CH 2 Cl 2  (16 mL) was added dropwise over 20 min. The resulting mixture was stirred at −40° C. for 40 min. The reaction mixture was used in the next step without purification. LCMS (ES, m/z): 898.2 [M−H] − . 
     Step 8. (5R,7R,8S,12aR,14R,15R,15aS,18R)-2-(2-cyanoethoxy)-18-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10(12H)-olate 2,10-dioxide[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10 (12H)-diolate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     To the solution from Step 7 at 0° C. was added I 2  in pyridine/water (9/1) (3%, 1.76 mL) over 5 min. The mixture was stirred at rt for 40 min. Then, it was treated with a solution of Na 2 S 2 O 3 .5H 2 O (150 mg) in water (2 mL). After 5 min, the mixture was concentrated under reduced pressure. The residue was purified by reverse phase (C18) chromatography eluted with 0 to 45% ACN in aq NH 4 HCO 3  (0.04%) to give the product. LCMS (ES, m/z): 915.8 [M+H] + .  19 F-NMR (376 MHz, CD 3 OD): δ −198.70, −203.36 (2s, 1F).  31 P-NMR (162 MHz, CD 3 OD): δ −0.96, −1.75 (2s, 1P); −3.64, −4.71 (2s, 1P). 
     Step 9: (5R,7R,8S,12aR,14R,15R,15aS,18R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-18-fluorohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10(12H)-diolate 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     (5R,7R,8S,12aR,14R,15R,15aS,18R)-2-(2-cyanoethoxy)-18-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10(12H)-olate 2,10-dioxide (110 mg, 0.12 mmol) was dissolved in a solution of MeNH 2  in EtOH (30%, 15 mL), and the resulting solution was stirred at rt for 3 h. Then, it was concentrated, and the residue was purified by preparative-HPLC (Atlantis Prep T3 Column, 19×250 mm) eluted with 0 to 9% ACN in aq NH 4 HCO 3  (50 mM) to give the product. LCMS (ES, m/z): 686.9 [M−H] − .  1 H-NMR (400 MHz, D 2 O): δ 8.14 (s, 1H), 7.85 (s, 1H), 7.80 (s, 1H), 6.01 (s, 1H), 5.99 (d, J=8.5 Hz, 1H), 5.84-5.66 (m, 1H), 5.44 (d, J=3.6 Hz, 0.5H), 5.31 (d, J=3.6 Hz, 0.5H), 4.96 (d, J=3.9 Hz, 1H), 4.84 (s, 1H), 4.65-4.53 (m, 1H), 4.33-4.15 (m, 4H), 4.10 (d, J=8.2 Hz, 1H), 3.96 (d, J=8.2 Hz, 1H).  19 F-NMR (376 MHz, D 2 O): δ −199.02 (s, 1F).  31 P-NMR (162 MHz, D 2 O): δ −1.89 (s, 1P), −2.49 (s, 1P). 
     Examples 21 through 29, as shown in Table 2 below, were prepared according to procedures analogous to those outlined in Example 20 above using the appropriate monomers, described as Preparations or as obtained from commercial sources, in the coupling step. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] 
               
               
                   
               
             
            
               
                 21 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aR)-14- (6-amino-9H-purin-9-yl)-15-fluoro-2,10- dihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 659 
               
               
                   
               
               
                 22 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (6-amino-9H-purin-9-yl)-16-fluoro-2,10- dihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 659 
               
               
                   
               
               
                 23 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 677 
               
               
                   
               
               
                 24 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dihydroxy-2,10- oxidohexahydro-14H-15,12a-(epoxymethano)- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7(12H)-yl]- 1,9-dihydro-6H-purin-6-one 
                 669 
               
               
                   
               
               
                 25 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (6-amino-9H-purin-9-yl)-15-fluoro-2,10- dihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 659 
               
               
                   
               
               
                 26 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(2S,5R,7R,8S,10S,12aR,14R,15S,15aR,16R)-14- (6-amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 677 
               
               
                   
               
               
                 27 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(6- amino-9H-purin-9-yl)-2,10-dihydroxy-2,10- dioxidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 641 
               
               
                   
               
               
                 28 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dihydroxy-15- methyl-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 655 
               
               
                   
               
               
                 29 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,8R,12aR,15S,15aR)-14-(6- amino-9H-purin-9-yl)-15-fluoro-2,10-dihydroxy- 15-methyl-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
            
           
         
       
     
     Example 30: 2-amino-7-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-2,10,15,16-tetrahydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4-one 
     
       
         
         
             
             
         
       
     
     cGAS buffer consisted of 40 mM Tris-HCL, pH 7.5, 100 uM NaCl, 10 mM MgCl 2 . cGAS enzyme was purchased from Novoprotein (Novoprotein code: SGCAS), having been expressed in  E. coli  and purified using a HIS tag. The calculated molecular weight was 55.3 kDa, and the sequence was: 
     
       
         
           
               
            
               
                 (SEQ. ID. NO. 1) 
               
               
                 MAHHHHHHGSDSEVNQEAKPEVKPEVKPETHINLKVSDGSSEIFFKIKKT 
               
               
                   
               
               
                 TPLRRLMEAFAKRQGKEMDSLTFLYDGIEIQADQTPEDLDMEDNDIIEAH 
               
               
                   
               
               
                 REQIGGENLYFQGGASKLRAVLEKLKLSRDDISTAAGMVKGVVDHLLLRL 
               
               
                   
               
               
                 KCDSAFRGVGLLNTGSYYEHVKISAPNEFDVMFKLEVPRIQLEEYSNTRA 
               
               
                   
               
               
                 YYFVKFKRNPKENPLSQFLEGEILSASKMLSKFRKIIKEEINDIKDTDVI 
               
               
                   
               
               
                 MKRKRGGSPAVTLLISEKISVDITLALESKSSWPASTQEGLRIQNWLSAK 
               
               
                   
               
               
                 VRKQLRLKPFYLVPKHAKEGNGFQEETWRLSFSHIEKEILNNHGKSKTCC 
               
               
                   
               
               
                 ENKEEKCCRKDCLKLMKYLLEQLKERFKDKKHLDKFSSYHVKTAFFHVCT 
               
               
                   
               
               
                 QNPQDSQWDRKDLGLCFDNCVTYFLQCLRTEKLENYFIPEFNLFSSNLID 
               
               
                   
               
               
                 KRSKEFLTKQIEYERNNEFPVFDEF 
               
            
           
         
       
     
     To a vial were added Herring DNA (CAS #9007-49-2, 0.3 mg/mL in cGAS buffer; 14.8 mL) and cGAS enzyme (3.1 mg/mL in cGAS buffer; 0.78 mL), and the mixture was incubated at RT for 15 min. 7-Deaza-GTP (TriLink catalog # N-1044; 5 mM in cGAS buffer, 1.95 mL, 9.75 μmol) and ATP (5 mM in cGAS buffer, 1.95 mL, 9.75 μmol) were added, and the mixture was incubated on a Radleys Metz heater shaker set to maintain 37° C. while shaking at 250 rpm for 16 h, after which the mixture was filtered and lyopholyzed. The product was purified using mass-directed reverse phase HPLC with a Waters SunFire C18 OBD Prep Column, 100 Å, 5 μm, 19 mm×150 mm, [Waters Part #186002568] using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate. Lyopholization of the product fractions furnished the title compound. LCMS (ES, m/z): 672 [M−H] − .  1 H NMR (600 MHz, DMSO-d 6 ) δ 10.33 (s, 1H), 8.37 (s, 1H), 8.10 (s, 1H), 7.56 (s, 1H), 7.24 (s, 2H), 6.94 (d, J=3.4 Hz, 1H), 6.28-6.24 (m, 3H), 6.01 (d, J=8.1 Hz, 1H), 5.86 (d, J=7.9 Hz, 1H), 5.61 (s, 1H), 5.01-4.97 (m, 1H), 4.86-4.83 (m, 1H), 4.70 (s, 1H), 4.25 (s, 1H), 4.21 (dd, J=10.4, 4.8 Hz, 1H), 4.03-3.92 (4, 3H), 3.80-3.75 (m, 1H), 3.69 (d, J=12.1 Hz, 1H), 2.76 (s, 12H), 1.02 (S, 18H). 
     Examples 31 to 65 in Table 3 below were made using procedures analogous to those described above for Example 30 using the appropriate nucleoside triphosphate monomers. Where necessary, the triphosphates were formed according to methods similar to those described for Preparations 23 to 26 or by submission of the requisite 5′-OH nucleoside monomer to NuBlocks LLC (Oceanside, Calif.). Example 38 was made using ATP and α-thio-GTP (BIOLOG Life Science Institute, catalog # G014/G015). 
     
       
         
           
               
               
               
               
             
               
                 TABLE 3 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                   
               
               
                 31 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- {(5R,7R,8R,12aR,14R,15R,15aS,16R)- 2,10,15,16-tetrahydroxy-14-[6- (methyl amino)-9H-purin-9-yl]-2,10- dioxidooctahydro-12H-5,8-methanofuro [3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl}- 1,9-dihydro-6H-purin-6-one 
                 687 
               
               
                   
               
               
                 32 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (6-chloro-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 692 
               
               
                   
               
               
                 33 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (4-amino-5-fluoro-7H-pyrrolo[2,3- d]pyrimidin-7-yl)-2,10,15,16-tetrahydroxy- 2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 690 
               
               
                   
               
               
                 34 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (6-amino-2-fluoro-9H-purin-9-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 691 
               
               
                   
               
               
                 35 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)- 14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7- yl)-2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 657 
               
               
                   
               
               
                 36 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5S,7R,8R,12aR,14R,15R,15aS,16R)-16- (aminomethyl)-14-(6-amino-9H-purin-9- yl)-2,10,15-trihydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 686 
               
               
                   
               
               
                 37 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-7- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4- one 
                 671 
               
               
                   
               
               
                 38 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (6-amino-9H-pufin-9-yl)-2,10,15,16- tetrahydroxy-10-oxido-2-sulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 689 
               
               
                   
               
               
                 39 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16S)-14- (6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 40 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14S,15S,15aS,16R)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 41 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14S,15S,15aS,16R)-14- (4-aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 672 
               
               
                   
               
               
                 42 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (2,6-diamino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 688 
               
               
                   
               
               
                 43 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)- 10,15,16-trihydroxy-2,10-dioxido-2- sulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 688 
               
               
                   
               
               
                 44 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)- 14-(6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,9-dihydro-1H-purine-2,6-dione 
                 674 
               
               
                   
               
               
                 45 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5S,7R,8R,12aR,14R,15R,15aS)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)- 2,10,15-trihydroxy-2,10-dioxidooctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 656 
               
               
                   
               
               
                 46 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5S,7R,8R,12aR,14R,15R,15aS,16S)-14- (6-amino-9H-purin-9-yl)-5-fluoro- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 691 
               
               
                   
               
               
                 47 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)- 14-(2,6-diamino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 48 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aS,16R)-14- (6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 49 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14S,15S,15aS,16R)-14- (7-amino-1H-pyrazolo[4,3-d]pyrimidin-3- yl)-2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 50 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(6- amino-9H-purin-9-yl)-2,10,15-trihydroxy- 2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 642 
               
               
                   
               
               
                 51 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (4-amino-1H-imidazo[4,5-c]pyridin-1-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 672 
               
               
                   
               
               
                 52 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,16S)-14- (6-amino-9H-purin-9-yl)-16-fluoro-2,10,15- trihydroxy-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 675 
               
               
                   
               
               
                 53 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purine-6-thione 
                 689 
               
               
                   
               
               
                 54 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14S,15S,15aS,16R)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 55 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5- d]pyrimidin-3-yl)-2,10,15,16-tetrahydroxy- 2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 674 
               
               
                   
               
               
                 56 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (6-ethyl-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 686 
               
               
                   
               
               
                 57 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- {(5R,7R,8R,12aR,14R,15R,15aS,16R)- 2,10,15,16-tetrahydroxy-14-[6-(2- methoxyethyl)-9H-purin-9-yl]-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl}- 1,9-dihydro-6H-purin-6-one 
                 716 
               
               
                   
               
               
                 58 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 1-[(5R,7R,8R,12aR,14R,15R,15aS,16R)- 14-(6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,5-dihydro-4H-imidazo[4,5-c]pyridin-4- one 
                 657 
               
               
                   
               
               
                 59 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (2-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 60 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 4-amino-7- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 7H-pyrrolo[2,3-d]pyrimidine-5-carbonitrile 
                 697 
               
               
                   
               
               
                 61 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 1-[(5R,7R,8R,12aR,14R,15R,15aS,16R)- 14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7- yl)-2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,5-dihydro-4H-imidazo[4,5-c]pyridin-4- one 
                 656 
               
               
                   
               
               
                 62 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5S,7R,8R,12aR,14R,15R,15aS)-14-(6- amino-9H-purin-9-yl)-2,10,15-trihydroxy- 16-methylidene-2,10-dioxidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]/ pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 669 
               
               
                   
               
               
                 63 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 7-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-7- (6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,7-dihydro-4H-imidazo[4,5- d][1,2,3]triazin-4-one 
                 659 
               
               
                   
               
               
                 64 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (7-amino-3H-imidazo[4,5-b]pyridin-3-yl)- 2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 672 
               
               
                   
               
               
                 65 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 1-[(5R,7R,8R,12aR,14R,15R,15aS,16R)- 14-(6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,5-dihydro-4H-imidazo[4,5-d]pyridazin-4- one 
                 658 
               
               
                   
               
            
           
         
       
     
     Example 66: 1-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-2,10,15,16-tetrahydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-one 
     
       
         
         
             
             
         
       
     
     cGAS buffer consisted of 40 mM Tris-HCL, pH 7.5, 100 uM NaCl, 10 mM MgCl 2 . cGAS enzyme was purchased from Novoprotein (Novoprotein code: SGCAS), having been expressed in  E. coli  and purified using a HIS tag. The calculated molecular weight was 55.3 kDa, and the sequence was: 
     
       
         
           
               
            
               
                 (SEQ. ID. NO. 1) 
               
               
                 MAHHHHHHGSDSEVNQEAKPEVKPEVKPETHINLKVSDGSSEIFFKIKKT 
               
               
                   
               
               
                 TPLRRLMEAFAKRQGKEMDSLTFLYDGIEIQADQTPEDLDMEDNDIIEAH 
               
               
                   
               
               
                 REQIGGENLYFQGGASKLRAVLEKLKLSRDDISTAAGMVKGVVDHLLLRL 
               
               
                   
               
               
                 KCDSAFRGVGLLNTGSYYEHVKISAPNEFDVMFKLEVPRIQLEEYSNTRA 
               
               
                   
               
               
                 YYFVKFKRNPKENPLSQFLEGEILSASKMLSKFRKIIKEEINDIKDTDVI 
               
               
                   
               
               
                 MKRKRGGSPAVTLLISEKISVDITLALESKSSWPASTQEGLRIQNWLSAK 
               
               
                   
               
               
                 VRKQLRLKPFYLVPKHAKEGNGFQEETWRLSFSHIEKEILNNHGKSKTCC 
               
               
                   
               
               
                 ENKEEKCCRKDCLKLMKYLLEQLKERFKDKKHLDKFSSYHVKTAFFHVCT 
               
               
                   
               
               
                 QNPQDSQWDRKDLGLCFDNCVTYFLQCLRTEKLENYFIPEFNLFSSNLID 
               
               
                   
               
               
                 KRSKEFLTKQIEYERNNEFPVFDEF 
               
            
           
         
       
     
     To a vial were added Herring DNA (CAS #9007-49-2, 0.3 mg/mL in cGAS buffer; 15.2 mL) and cGAS enzyme (3.1 mg/mL in cGAS buffer; 0.8 mL), and the mixture was incubated at RT for 15 min. ATP (5 mM in cGAS buffer, 2.0 mL, 10 μmol), 7-deaza-8-aza-ITP (5 mM in cGAS buffer, 2.0 mL, 10 μmol), and DMSO (5 mL) were added, and the mixture was incubated on a Radleys Metz heater shaker set to maintain 37° C. while shaking at 250 rpm for 3d. The mixture was filtered, lyopholyzed, and purified by reverse phase HPLC (eluting acetonitrile/water gradient with 100 mM TEAA modifier, linear gradient) to afford the title compound as the TEA salt. LCMS (ES, m/z): 658 [M−H] − .  1 H NMR (600 MHz, D 2 O): δ 8.36 (s, 1H), 8.34 (s, 1H), 8.13 (s, 1H), 7.51 (s, 1H), 6.41 (d, J=8.2 Hz, 1H), 6.24 (s, 1H), 5.69 (m, 1H), 5.42 (m, 1H), 4.88 (d, J=4.4 Hz, 1H), 4.66 (d, J=4.1 Hz, 1H), 4.51 (m, 1H), 4.43 (m, 2H), 4.23 (m, 2H), 4.01 (m, 1H). 
     Examples 67 to 74 in Table 4 below were made using procedures analogous to those described above for Example 66 using the appropriate nucleoside triphosphate monomers. 
     Where necessary, the triphosphates were formed according to methods similar to those described for Preparations 23 to 26 or by submission of the requisite 5′-OH nucleoside monomer to NuBlocks LLC (Oceanside, Calif.). 
     
       
         
           
               
               
               
               
             
               
                 TABLE 4 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                 67 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)- 2,10,15-trihydroxy-2,10-dioxidooctahydro- 12H-5,8-methanofuro [3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 641 
               
               
                   
               
               
                 68 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 7-[(5R,7S,8R,12aR,14R,15R,15aS,16R)-14- (6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro [3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7- yl]imidazo[2,1-f][1,2,4]triazin-4(3H)-one 
                 658 
               
               
                   
               
               
                 69 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one 
                 674 
               
               
                   
               
               
                 70 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)- 2,10,15,16-tetrahydroxy-14-(6-methyl-9H- purin-9-yl)-2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 672 
               
               
                   
               
               
                 71 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (4-chloro-7H-pyrrolo[2,3-d]pyrimidin-7- yl)-2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 691 
               
               
                   
               
               
                 72 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)- 2,10,15,16-tetrahydroxy-2,10-dioxido-14- (9H-purin-9-yl)octahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 658 
               
               
                   
               
               
                 73 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)-14- (4-amino-1H-[1,2,3]triazolo[4,5-c]pyridin- 1-yl)-2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one 
                 673 
               
               
                   
               
               
                 74 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 3-[(5R,7S,8R,12aR,14R,15R,15aS,16R)-14- (6-amino-9H-purin-9-yl)-2,10,15,16- tetrahydroxy-2,10-dioxidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7- one 
                 658 
               
               
                   
               
            
           
         
       
     
     Example 75: 2-Amino-9-[(5S,7R,8R,12aR,14R,15R,15aS,16R)-16-amino-14-(6-amino-9H-purin-9-yl)-2,10,15-trihydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][11,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     Step 1: 2-Amino-9-[(5S,7R,8R,12aR,14R,15R,15aS,16R)-16-amino-14-(6-amino-9H-purin-9-yl)-2,10,15-trihydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To a stirred solution of 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-azido-2,10,15-trihydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Example 14, 4.0 mg, 0.0055 mmol) in absolute EtOH (1.0 mL) and deionized water (1.0 mL) was added palladium on carbon (1.0 mg, 10 wt. % loading) in one portion under Ar at RT. The reaction vessel was then flushed with hydrogen gas and attached to a hydrogen gas balloon. The reaction mixture was left to stir for 48 h, filtered, and concentrated to afford the title compound. LCMS (ES, m/z): 672 [M−H] − . (600 MHz, DMSO-d 6 ) δ 10.70 (s, 1H), 8.42 (s, 1H), 8.12 (s, 1H), 7.96 (s, 1H), 7.70 (s, 1H), 7.29 (br, 2H), 6.56 (br, 2H), 6.00 (d, J=8.3 Hz, 1H), 5.89 (d, J=8.5 Hz, 1H), 5.21 (s, 1H), 5.04 (t, J=6.0 Hz, 1H), 4.16 (s, 1H), 4.05 (dd, J=10.5, 5.0 Hz, 1H), 4.00 (s, 1H), 3.77 (d, J=4.1 Hz, 1H), 3.67 (m, 2H).  31 P NMR: (202 MHz, DMSO-d 6 ): δ −0.4 (s), 2.0 (s). 
     Alternatively, Example 75 may be prepared from the requisite monomers, according to a method similar to that described above for Example 30. 
     Example 76: 9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-2,10,15,16-tetrahydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purine-6-carboxamide 
     
       
         
         
             
             
         
       
     
     To a stirred solution of 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-14-(6-chloro-9H-purin-9-yl)-2,10,15,16-tetrahydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one, (Example 32, 16 mg, 0.018 mmol) in DMSO (1.7 mL) was added sodium cyanide (8.0 mg, 0.16 mmol) in one portion under Ar at RT. The reaction mixture was heated to 80° C. and left to stir at the same temperature for 3 h, cooled to ambient temperature, then quenched with cold acetic acid (15 uL). The mixture was filtered and lyophilyzed. The product was purified using mass-directed reverse phase HPLC with a Waters SunFire C18 OBD Prep Column, 100 Å, 5 μm, 19 mm×150 mm, [Waters Part #186002568] using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate. Lyophilization of the product fractions furnished 9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-2,10,15,16-tetrahydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purine-6-carbonitrile. LCMS (ES, m/z): 683 [M−H] − . 
     To a stirred suspension of 9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-2,10,15,16-tetrahydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purine-6-carbonitrile (3.0 mg, 0.003 mmol) in deionized water (338 uL) was added Hydrido(dimethylphosphinous acid-kP)[hydrogen bis(dimethylphosphinito-kP)]platinum(II) (1.0 mg, 0.002 mmol). The reaction mixture was heated to 85° C. and left to stir at the same temperature for 6 h, cooled to ambient temperature, filtered and lyopholyzed. The product was purified using mass-directed reverse phase HPLC with a Waters SunFire C18 OBD Prep Column, 100 Å, 5 μm, 19 mm×150 mm, [Waters Part #186002568] using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate. Lyopholization of the product fractions furnished 9-[(5R,7R,8R,12aR,14R,15R,15aS,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-2,10,15,16-tetrahydroxy-2,10-dioxidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purine-6-carboxamide. LCMS (ES, m/z): 701 [M−H] − .  1 H NMR (500 MHz, DMSO): δ 10.58 (s, 1H), 9.06 (s, 1H), 8.36 (s, 1H), 8.05 (s, 1H), 7.91 (s, 1H), 7.74 (s, 1H), 6.55 (br, 4H), 6.07 (d, J=7.7 Hz, 1H), 5.81 (d, J=6.0 Hz, 1H), 5.77 (m, 1H), 5.04 (m, 1H), 4.96 (d, J=4.5 Hz, 1H), 4.60 (m, 1H), 4.27 (m, 1H), 4.07-4.04 (m, 2H), 3.99-3.75 (m, 2H).  31 P NMR: (202 MHz, DMSO): δ 1.9 (s), −0.8 (s). 
     Examples 77, 78, 79, 80: 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15-hydroxy-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1-4) 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     Step 1. (2R,3R)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate 
     
       
         
         
             
             
         
       
     
     To a flask was added (2R,3R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (4.00 g, 4.76 mmol), MeCN (23.65 ml), and water (0.158 ml). Pyridine trifluoroacetate (1.104 g, 5.71 mmol) was added, and the reaction was stirred at rt for 1 h. Tert-butylamine (20.02 ml, 190 mmol) was then added, and stirring was continued at rt for 1 h, after which time the reaction was partitioned between hexanes and acetonitrile. The acetonitrile layer was collected and concentrated under vacuum. DCM (39.9 ml) and water (0.798 ml) were added, followed by dichloroacetic acid (55.1 ml, 33.3 mmol), and the solution was stirred for 20 min at rt, after which time triethylsilane (133 ml, 833 mmol) was added, and the reaction was stirred for a further 2 h at rt. The reaction was cooled to 0° C., and pyridine (5.39 mL 66.6 mmol) was added. Then the mixture was concentrated under reduced pressure to give the title compound, which was not purified further. LCMS (ES, m/z): 400 [M−H] − . 
     Step 2: O-((2R,3R,4R,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)tetrahydrofuran-3-yl) 0-(((2S,4R,5R)-4-((hydroxyhydrophosphoryl)oxy)-5-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-2-yl)methyl)O-hydrogen phosphorothioate 
     
       
         
         
             
             
         
       
     
     To a flask was added (2R,3R,5S)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate (335 mg, 0.836 mmol) and MeCN (20 mL), and then the solution was concentrated under reduced pressure. This process was repeated 2×, and then MeCN (8 mL) was added, followed by activated 4 Å sieves. The mixture was stirred for 20 min at rt. (2R,3R,4R,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl) oxy)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (825 mg, 0.836 mmol) was dissolved in MeCN (5 mL). Molecular sieves (4 Å) were added, and the mixture was stirred for 30 min at rt, after which time this solution was transferred to the hydrogen phosphonate solution and 2×1.5 mL portions of MeCN were used to complete the transfer. After stirring 30 min at rt, ((dimethylamino-methylidine)amino)-3H-1,2,4-dithiazoline-3-thione (189 mg, 0.919 mmol) was added. After stirring 5 min at rt, the mixture was concentrated under reduced pressure and purified using reverse phase HPLC with a 10-100% gradient of MeCN and 100 mM aqueous triethylammonium acetate. The product-containing fractions were collected and lyophilized, during which time the cyanoethyl protecting group was cleaved, to furnish O-((2R,3R,4R,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy) methyl)-4-((tert-butyldimethylsilyl)oxy)tetrahydrofuran-3-yl) O-(((2S,4R,5R)-4-((hydroxyhydrophosphoryl)oxy)-5-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-2-yl)methyl)O-hydrogen phosphorothioate. LCMS (ES, m/z): 1264 [M−H] − . 
     Step 3: N-{7-[(5S,7R,8R,12aR,14R,15R,15aR)-15-{[tert-butyl(dimethyl)silyl]oxy}-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide (Diastereomers 14) 
     
       
         
         
             
             
         
       
     
     To a flask containing O-((2R,3R,4R,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy) tetrahydrofuran-3-yl)O-(((2 S,4R,5R)-4-((hydroxyhydrophosphoryl)oxy)-5-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-2-yl)methyl)O-hydrogen phosphorothioate (581 mg, 0.440 mmol) was added DCM (8.81 mL), water (0.079 mL, 4.40 mmol) and then dichloroacetic acid (8.74 mL, 5.28 mmol). The mixture was stirred for 15 min at rt, and then triethylsilane (10.97 mL, 68.7 mmol) was added. The mixture was stirred at rt for 1.5 h and then concentrated under reduced pressure. The mixture was dissolved in pyridine (10 mL) and then concentrated under reduced pressure. This process was repeated 2×, and then the resulting sample was dissolved in pyridine (17 ml) and 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinan-2-one (81 mg, 0.440 mmol) was added in 1 portion at rt. After stirring for 30 min at rt, additional 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinan-2-one (81 mg, 0.440 mmol) was added. This sequence was repeated twice, and then water (238 μl, 13.19 mmol) and 3H-1,2-benzodithiol-3-one (111 mg, 0.660 mmol) were added. The mixture was stirred for 1 h at rt and then partitioned between water (10 mL) and 1:1 EtOAc/ether (10 mL). The layers were separated, and the aqueous phase was extracted with 1:1 EtOAc/ether (3×10 mL). The combined organic phases were dried (MgSO 4 ), filtered, and concentrated under reduced pressure. Reverse phase HPLC purification (gradient of 30-100% MeCN and 100 mM aqueous triethylammonium acetate) furnished 4 diastereomers of N-{7-[(5S,7R,8R,12aR,14R,15R,15aR)-15-{[tert-butyl(dimethyl) silyl]oxy}-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide, all of which showed LCMS (ES, m/z): 976 [M−H] − . 
     Step 4: 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15-hydroxy-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1-4) 
     
       
         
         
             
             
         
       
     
     To a flask containing N-{7-[(5S,7R,8R,12aR,14R,15R,15aR)-15-{[tert-butyl(dimethyl)silyl]oxy}-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide (fastest eluting peak, 7.4 mg, 7.57 μmol) was added methylamine (33% in EtOH) (1 mL, 8.03 mmol), and the mixture was stirred at rt for 4 h, after which time the mixture was concentrated under reduced pressure. Pyridine (1 mL) was added, and the mixture was concentrated under reduced pressure. Then, pyridine (0.5 ml), triethylamine (0.104 ml, 0.746 mmol) and triethylamine trihydrofluoride (0.030 ml, 0.187 mmol) were added, and the mixture was stirred at 50° C. for 16 h, after which time the mixture was cooled to rt and concentrated under reduced pressure. Purification by reverse phase HPLC (gradient of acetonitrile and 100 mM aqueous triethylammonium acetate) furnished Example 77, 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15-hydroxy-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1). LCMS (ES, m/z): 688 [M−H] − .  1 H NMR (600 MHz, Deuterium Oxide) δ 8.06 (s, 1H), 8.03 (s, 1H), 7.41 (d, J=3.8 Hz, 1H), 6.25 (d, J=3.7 Hz, 1H), 6.17 (d, J=2.6 Hz, 1H), 5.68 (d, J=7.5 Hz, 1H), 5.42-5.36 (m, 2H), 5.10-5.06 (m, 1H), 4.83-4.81 (m, 1H), 4.51-4.48 (m, 1H), 4.36-4.33 (m, 1H), 4.28 (dt, J=10.1, 4.9 Hz, 1H), 4.06-3.94 (m, 2H), 3.03 (q, J=7.3 Hz, 12H), 2.44-2.40 (m, 2H), 1.11 (t, J=7.3 Hz, 18H). 
     The other diastereomers from Step 3 were individually processed in an analogous manner to afford three additional diastereomeric products: 
     Example 78: 2-Amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15-hydroxy-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2). LCMS (ES, m/z): 688 [M−H] − .  1 H NMR (600 MHz, Deuterium Oxide) δ 8.04 (s, 1H), 7.75 (s, 1H), 7.50 (d, J=3.6 Hz, 1H), 6.19-6.17 (m, 1H), 6.16 (d, J=3.7 Hz, 1H), 5.65 (d, J=7.4 Hz, 1H), 5.63-5.57 (m, 1H), 5.14 (td, J=7.8, 4.4 Hz, 1H), 4.54 (d, J=4.2 Hz, 1H), 4.52-4.46 (m, 1H), 4.33 (d, J=8.9 Hz, 1H), 4.27 (dd, J=11.9, 3.1 Hz, 1H), 4.18-4.15 (m, 1H), 3.96 (dd, J=11.4, 3.6 Hz, 2H), 3.04 (q, J=7.3 Hz, 12H), 2.44-2.36 (m, 2H), 1.11 (t, J=7.3 Hz, 18H). 
     Example 79: 2-Amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15-hydroxy-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3). LCMS (ES, m/z): 688 [M−H] − .  1 H NMR (600 MHz, Deuterium Oxide) δ 8.00 (s, 1H), 7.97 (s, 1H), 7.19 (d, J=3.8 Hz, 1H), 6.15 (d, J=3.8 Hz, 2H), 5.66 (d, J=7.3 Hz, 1H), 5.32 (dq, J=9.9, 7.2 Hz, 1H), 4.95 (td, J=8.6, 4.6 Hz, 1H), 4.81 (d, J=4.4 Hz, 1H), 4.50 (d, J=8.0 Hz, 1H), 4.32 (d, J=7.8 Hz, 1H), 4.25 (dt, J=12.0, 3.6 Hz, 1H), 4.05-3.97 (m, 3H), 3.03 (q, J=7.3 Hz, 12H), 2.51-2.41 (m, 2H), 1.11 (t, J=7.3 Hz, 18H). 
     Example 80: 2-Amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15-hydroxy-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 4). LCMS (ES, m/z): 688 [M−H] − .  1 H NMR (600 MHz, Deuterium Oxide) δ 8.00 (s, 1H), 7.72 (s, 1H), 7.23 (d, J=3.8 Hz, 1H), 6.14 (s, 1H), 6.12 (d, J=3.7 Hz, 1H), 5.64 (d, J=6.9 Hz, 1H), 5.47 (dq, J=14.2, 7.0 Hz, 1H), 5.05 (td, J=8.0, 4.5 Hz, 1H), 4.52 (d, J=4.4 Hz, 1H), 4.49 (dt, J=7.4, 2.7 Hz, 1H), 4.33-4.27 (m, 2H), 4.19 (ddd, J=11.5, 8.5, 3.0 Hz, 1H), 4.00 (dd, J=11.5, 3.9 Hz, 1H), 3.94 (ddd, J=11.6, 5.6, 2.2 Hz, 1H), 3.01 (q, J=7.3 Hz, 12H), 2.49-2.40 (m, 2H), 1.10 (t, J=7.3 Hz, 18H). 
     Example 81: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10,16-trihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3R,4R,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl) methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (3 g, 3.09 mmol) in MeCN (15 mL) at 25° C. was added H 2 O (0.111 mL, 6.18 mmol) and pyridin-1-ium 2,2,2-trifluoroacetate (0.717 g, 3.71 mmol). The resulting mixture was stirred at 25° C. for 20 min. The reaction progress was monitored by LCMS/TLC. After the phosphoramidite starting material was consumed, the reaction mixture that containing the desired product (major) was used for the next step without any after-treatment. LCMS (ES, m/z): 887.4 [M+H] + . 
     Step 2: (2R,3R,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of the product of Step 1 (15.0 mL, 142 mmol) from the previous reaction was added tert-butylamine in one portion, and it was stirred at 25° C. for 40 min. The resulting solution was concentrated in vacuo. The residue was co-evaporated with dry MeCN (two times, 15 mL each), used for the next step without purification. LCMS (ES, m/z): 832.3 [M−H] − . 
     Step 3: (2R,3R,4R,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of the product of Step 2 in CH 2 Cl 2  (37 mL) was added H 2 O (0.558 mL, 31.0 mmol) and 6% DCA in CH 2 Cl 2  (37 mL, 31.5 mmol) dropwise. The resulting mixture was stirred at 25° C. for 40 min, then Et 3 SiH (60 mL) was added, and the reaction mixture was stirred for 1.5 h. Pyridine (4.5 mL, 2eq to DCA) was added to the reaction. The resulting solution was stirred at 25° C. for 5 min and then concentrated in vacuo. The residue was triturated with MTBE/hexane (100 mL, v/v, 1/1), and the supernatant was decanted. This process was repeated two more times. The final residue was concentrated at reduced pressure and was used for the next step without purification. LCMS (ES, m/z): 532.18 [M+H] + . 
     Step 4. (2R,3R,4R,5R)-5-((((((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of the product of Step 3 (0.704 g, 0.722 mmol) in MeCN (5 mL) under Ar was added activated 4 Å molecular sieve (200 mg), and the mixture was stirred at RT over 30 min. (2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl) methoxy)methyl)-4-fluorotetrahydrofuran-3-yl (2-cyanoethyl) diisopropyl-phosphoramidite (0.822 g, 0.939 mmol) was twice co-evaporated with dry MeCN (3 mL). Activated 4 Å molecular sieve (200 mg) was added. After 30 min, the phosphoramidite solution was transferred into the solution of the product of Step 3 by syringe. The resulting mixture was stirred at RT for 20 min. The desired product was detected by TLC/LCMS, and the reaction solution was used for the next reaction without purification. LCMS (ES, m/z): 1306.7 [M+H] + . 
     Step 5. (2R,3R,4R,5R)-5-((((((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture containing the product of Step 4 (˜0.722 mmol) under Ar was added (E)-N,N-dimethyl-N′-(3-thioxo-3H-1,2,4-dithiazol-5-yl)formimidamide (163 mg, 0.794 mmol) in one portion, and the mixture was stirred at RT for 30 min. The reaction progress was monitored by TLC/LCMS. After the consumption of the starting phosphite, the reaction mixture was concentrated in vacuo, and the residue was purified by reverse phase chromatography (X-Bridge BEH130 Prep C18) eluting with 5 to 95% MeCN in H 2 O (0.04% NH 4 HCO 3 ). The product-containing fractions were combined and concentrated under reduced pressure to 2/3 volume. NaCl (10 g) was added, and the aqueous mixture was extracted with EtOAc/Et 2 O (v/v, 1/1, 3×80 mL). The combined organic layers were dried (Na 2 SO 4 ) and concentrated. LCMS (ES, m/z): 1339.5 [M+H] + .  31 P-NMR (162 MHz, CD 3 OD): δ 67.83 (d, J=43.9 Hz), 2.81 (d, J=15.7 Hz). 
     Step 6. (2R,3R,4R,5R)-5-((((((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of the product of Step 5 (180 mg, 0.128 mmol) in CH 2 Cl 2  (7 mL) was added 2,2-dichloroacetic acid in CH 2 Cl 2  (2.47 mg, 1.15 mmol) and H 2 O (22.97 mg, 1.28 mmol). After stirring at RT for 20 min, Et 3 SiH (4.5 mL) was added. After 2 h, pyridine (1 mL) was added, and the mixture was stirred for 10 min. After removal of volatiles, the product was used for the next reaction step without purification. LCMS (ES, m/z): 1036.4 [M+H] + . 
     Step 7: (5R,7R,8R,12aR,14R,15R,15aR,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-15-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2-sulfide 
     
       
         
         
             
             
         
       
     
     The product of Step 6 (570 mg) was co-evaporated with dry pyridine (1 mL each, three times). To the mixture in dry pyridine (4 mL) at RT under Ar was added 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphinane 2-oxide (71 mg, 0.384 mmol) in one portion. The resulting mixture was stirred for 40 min. The reaction progress was monitored by TLC/LCMS. The desired product as a mixture of diastereomers was observed, and the product was used for the next reaction step directly. LCMS (ES, m/z): 1018.5 [M+H] + . 
     Step 8: Diastereomeric mixtures (5R,7R,8R,12aR,14R,15R,15aR,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-15-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-10-thiolate 10-oxide 2-sulfide (A1) and (5R,7R,8R,12aR,14R,15R,15aR,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-15-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-10-thiolate 10-oxide 2-sulfide (A2) 
     
       
         
         
             
             
         
       
     
     To the stirred mixture of the product of Step 7 was added H 2 O (69.2 mg, 3.84 mmol) and 3H-benzo[c][1,2]dithiol-3-one (32.3 mg, 0.192 mmol). The mixture was stirred at RT for 40 min. The reaction progress was monitored by TLC/LCMS. After the reaction completed, the reaction mixture was poured into aq NaHCO 3  (0.14 g NaHCO 3  in 5 mL H 2 O) and stirred for 5 min. The resulting mixture was extracted with EtOAc/ether (v/v, 1/1, 3×15 mL). The combined organic layers were dried (Na 2 SO 4 ), and purified by silica gel chromatography eluted with 0 to 15% MeOH in CH 2 Cl 2  to give products: mixture of diastereomers A1 (eluted out at 5.5% MeOH in CH 2 Cl 2 ); mixture of diastereomers A2 (eluted out at 9.8% MeOH in CH 2 Cl 2 ); (2R,3R,4R,5R)-5-((((((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl) oxy)methyl)-4-((tert-butyldimethyl silyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (eluted out at 12.6% MeOH in CH 2 Cl 2 ). Mixture A1: LCMS (ES, m/z): 1050.30 [M+H] + .  31 P-NMR (162 MHz, CD 3 OD): δ 66.34 (s), 64.63 (s). Mixture A2: LCMS (ES, m/z): 1050.30 [M+H] + .  31 P-NMR (162 MHz, CD 3 OD): δ 65.94, 64.17, 62.55, 61.28. 
     Step 9: Diastereomers (5R,7R,8R,12aR,14R,15R,15aR,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-15-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-bis(thiolate) 2,10-dioxide (BI) and (5R,7R,8R,12aR,14R,15R,15aR,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-15-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-bis(thiolate) 2,10-dioxide (B2) 
     
       
         
         
             
             
         
       
     
     To a stirred suspension of crude A1 (95 mg, ˜0.09 mmol) from the previous step in MeCN (1 mL) at RT under Ar was added tert-butylamine (1.5 mL). After 30 min, volatile components were removed in vacuo. The residue was purified by reverse phase prep-HPLC (X-Bridge BEH130 Prep C18) eluted with 25 to 45% MeCN in aq NH 4 HCO 3  (10 mM) over 8 min to give compound B2 as a single diastereomer (T R =5.97 min). LCMS (ES, m/z): 891.4 [M−H] − . H-NMR (300 MHz, CD 3 OD): δ 8.44 (s, 1H), 8.22 (s, 1H), 8.09 (s, 1H), 6.37 (d, J=14.0 Hz, 1H), 5.95 (d, J=8.0 Hz, 1H), 5.65-5.54 (m, 1H), 5.26-5.10 (m, 2H), 4.57-4.41 (m, 4H), 4.24 (s, 1H), 4.01 (d, J=11.5 Hz, 1H), 3.89 (d, J=11.8 Hz, 1H), 2.75-2.63 (m, 1H), 1.04-0.91 (m, 15H), 0.28-0.24 (m, 6H).  31 P-NMR (121 MHz, CD 3 OD): δ 57.10 (s), 53.1 (s). 
     Step 10: (5R,7R,8R,12aR,14R,15R,15aR,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-6-{[tert-butyl(dimethyl)silyl]oxy}-15-fluorooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2, O-bis(thiolate) 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     To a stirred solution of compound B2 (13 mg, 0.013 mmol) from the previous step was added a solution of MeNH 2  in EtOH (0.6 mL, 30% by weight). The mixture was stirred at RT for 12 h. The volatile components were removed under reduced pressure, and the residue containing product compound was used for the next reaction step without purification. LCMS (ES, m/z): 823.15 [M+H] + . 
     Step 11: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10,16-trihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
     
       
         
         
             
             
         
       
     
     The crude product from Step 10 (25 mg) was co-evaporated with pyridine/Et 3 N (v/v, 3/1, 1 mL each, three times) and then dissolved in pyridine (0.15 mL). The mixture was charged with Ar and Et 3 N (0.20 mL) and triethylamine trihydrofluoride (56.4 mg, 0.350 mmol) were added. The resulting solution was warmed at 50° C. for 6 h. The reaction progress was monitored by TLC/LCMS. After completion of the reaction, the mixture was concentrated in vacuo and then, co-evaporated with MeCN (three times, 1 mL each). The residue was purified by reverse phase prep-HPLC (X-Bridge BEH130 Prep C18) eluted with 0 to 22% MeCN in aq NH 4 HCO 3  (50 mM) over 15 min to give the product compound (T R =8.3 min). LCMS (ES, m/z): 708.95 [M+H] + .  1 H-NMR (400 MHz, D 2 O): δ 8.18 (s, 1H), 8.16 (s, 1H), 7.77 (s, 1H), 6.37 (d, J=14.3 Hz, 1H), 5.86 (d, J=8.4 Hz, 1H), 5.61-5.54 (m, 1.5H), 5.43 (s, 0.5H), 5.27-5.12 (m, 2H), 4.59 (d, J=3.6 Hz, 1H), 4.47 (t, J=12.9 Hz, 2H), 4.36 (d, J=4.8 Hz, 1H), 4.04 (dd, J=23.2, 12.0 Hz, 2H).  31 P-NMR (162 MHz, D 2 O): δ 55.63 (s), 51.55 (s). 
     Example 82: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10,16-trihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
     
       
         
         
             
             
         
       
     
     Step 1: Diastereomers (5R,7R,8R,12aR,14R,15R,15aR,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-15-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-bis(thiolate) 2,10-dioxide (B3) and (5R,7R,8R,12aR,14R,15R,15aR,16R)-16-{[tert-butyl(dimethyl)silyl]oxy}-15-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-bis(thiolate) 2,10-dioxide (B4) 
     
       
         
         
             
             
         
       
     
     To a stirred suspension of crude A2 (105 mg, ˜0.1 mmol) from Example 81, Step 8 in MeCN (1 mL) under Ar was added tert-butylamine (1.5 mL), and the mixture was stirred at RT for 30 min. The volatile components were removed in vacuo. The residue was purified by reverse phase prep-HPLC (X-Bridge BEH130 Prep C18) eluted with 25 to 40% MeCN in aq NH 4 HCO 3  (10 mM) over 10 min to give two diastereomeric compounds, B3 (T R =6.12 min, 0.025 mmol) and B4 (T R =7.45 min, 0.021 mmol). 
     Compound B3: LCMS (ES, m/z): 995.3 [M−H] − . H-NMR (300 MHz, CD 3 OD): δ 8.82 (s, 1H), 8.72 (s, 1H), 8.65 (s, 1H), 8.20-8.13 (m, 2H), 7.66-7.54 (m, 3H), 6.47 (d, J=14.0 Hz, 1H), 6.09 (d, J=8.4 Hz, 1H), 5.96-5.95 (m, 0.5H), 5.81-5.78 (m, 0.5H), 5.52-5.36 (m, 2H), 4.64-4.56 (m, 2H), 4.48-4.43 (m, 1H), 4.37-4.30 (m, 1H), 4.25-4.22 (m, 1H), 4.17-4.10 (m, 1H), 3.98 (d, J=11.7 Hz, 1H), 2.65 (p, J=6.8 Hz, 1H), 1.12 (d, J=6.8 Hz, 3H), 0.98-0.95 (m, 12H), 0.22 (d, J=8.0 Hz, 6H).  31 P-NMR (121 MHz, CD 3 OD): δ 56.96 (s), 55.90 (s). 
     Compound B4: LCMS (ES, m/z): 995.4 [M−H] − . H-NMR (300 MHz, CD 3 OD): δ 8.97 (s, 1H), 8.68 (s, 1H), 8.24-8.22 (m, 3H), 7.59 (ddd, J=14.5, 7.9, 6.2 Hz, 3H), 6.46 (d, J=13.0 Hz, 1H), 5.99 (d, J=8.3 Hz, 1H), 5.67-5.57 (m, 1H), 5.45-5.33 (m, 2H), 4.56 (dd, J=13.5, 4.9 Hz, 2H), 4.47-4.38 (m, 2H), 4.25 (t, J=3.5 Hz, 1H), 4.07 (d, J=11.3 Hz, 1H), 3.94 (d, J=11.0 Hz, 1H), 2.75 (p, J=6.8 Hz, 1H), 1.04 (d, J=6.8 Hz, 3H), 0.95 (s, 12H), 0.23 (d, J=5.2 Hz, 6H).  31 P-NMR (121 MHz, CD 3 OD): δ 56.81 (s), 54.76 (s). 
     Step 2: (5R,7R,8R,12aR,14R,15R,15aR,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-16-{[tert-butyl(dimethyl)silyl]oxy}-15-fluorooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2, O-bis(thiolate) 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     Compound B3 from Step 1 (25 mg, 0.025 mmol) was dissolved in a solution of MeNH 2  in EtOH (1 mL, 30% by weight), and the mixture was stirred at RT for 12 h. The reaction progress was monitored by TLC/LCMS. After the reaction was complete, the volatile components were removed in vacuo, and the residue containing the crude product was used for the next reaction step without purification. LCMS (ES, m/z): 823.25 [M+H] + . 
     Step 3: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10,16-trihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
     
       
         
         
             
             
         
       
     
     The crude product of Step 2 (35 mg) was co-evaporated with pyridine/Et 3 N (v/v, 3/1, 1 mL each, three times) and then re-dissolved in pyridine (0.4 mL). The mixture was charged with Ar and Et 3 N (0.34 mL, 2.4 mmol), and triethylamine trihydrofluoride (97 mg, 0.6 mmol) were added. 
     The resulting solution was warmed at 50° C. for 6 h. Then, the mixture was concentrated at reduced pressure and then co-evaporated with MeCN (3×1 mL). The residue was purified by reverse phase prep-HPLC (X-Bridge BEH130 Prep C18) eluted with 0 to 10% MeCN in aq NH 4 HCO 3  (50 mM) over 14 min to give the product compound (T R =9.2 min). LCMS (ES, m/z): 709.00 [M+H] + . H-NMR (400 MHz, DMF-d 7 +D 2 O): δ 8.68 (s, 1H), 8.61 (s, 1H), 8.45 (s, 1H), 6.57 (d, J=14.8 Hz, 1H), 6.27-6.25 (m, 1.5H), 6.15-6.13 (m, 0.5H), 5.72-5.68 (m, 1H), 5.56-5.54 (m, 1H), 4.85-4.83 (m, 1H), 4.71-4.69 (m, 1H), 4.52-4.43 (m, 4H), 4.27-4.24 (m, 1H).  31 P-NMR (162 MHz, DMF-d 7 +D 2 O): δ 56.03 (s), 53.37 (s).  19 F-NMR (376 MHz, DMF-d 7 +D 2 O): δ −205.44 (s). 
     Example 83: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10,16-trihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
     
       
         
         
             
             
         
       
     
     Step 1: (5R,7R,8R,12aR,14R,15R,15aR,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-16-{[tert-butyl(dimethyl)silyl]oxy}-15-fluorooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-bis(thiolate) 2,10-dioxide 
     
       
         
         
             
             
         
       
     
     Compound B4 ((5R,7R,8R,12aR,14R,15R,15aR,16R)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-16-{[tert-butyl(dimethyl)silyl]oxy}-15-fluorooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-bis(thiolate) 2,10-dioxide, 21 mg, 0.021 mmol) from Example 82, Step 1 was dissolved in a solution of MeNH 2  in EtOH (1 mL, 30% by weight), and the mixture was stirred at RT for 12 h. The reaction progress was monitored by TLC/LCMS. After the reaction was complete, the volatile components were removed in vacuo, and the product was used for the next reaction step without purification. LCMS (ES, m/z): 823.25 [M+H] + . 
     Step 2: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10,16-trihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
     
       
         
         
             
             
         
       
     
     The crude product of Step 1 (31 mg) was co-evaporated with pyridine/Et 3 N (v/v, 3/1, 3×1 mL) and then, re-dissolved in pyridine (0.4 mL). The mixture was charged with Ar and Et 3 N (0.28 mL, 2.0 mmol) and triethylamine trihydrofluoride (81 mg, 0.5 mmol) were added. The resulting solution was warmed at 50° C. for 6 h. The mixture was concentrated at reduced pressure and then co-evaporated with MeCN (3×1 mL). The residue was purified by reverse phase prep-HPLC (X-Bridge BEH130 Prep C18) eluting with 0 to 10% MeCN in aq NH 4 HCO 3  (50 mM) over 14 min to give the product compound (T R =10.1 min). LCMS (ES, m/z): 709.00 [M+H] + . H-NMR (400 MHz, DMF-d 7 +D 2 O): δ 8.73 (s, 1H), 8.28-8.20 (m, 2H), 6.55 (d, J=14.8 Hz, 1H), 6.25-5.85 (m, 3H), 5.62-5.56 (m, 1H), 4.76 (s, 1H), 4.62-4.60 (m, 2H), 4.49-4.41 (m, 3H), 4.18-4.15 (m, 1H).  31 P-NMR (162 MHz, DMF-d 7 +D 2 O): δ 56.09 (s), 54.75 (s).  19 F-NMR (376 MHz, DMF-d 7 +D 2 O): δ −203.33 (s). 
     Examples 84 through 116, shown in Table 5 below, were prepared according to procedures analogous to those outlined in Examples 77 through 83 above using the appropriate monomers, described as Preparations or as obtained from commercial sources, in the coupling step. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 5 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                  84 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15aS,16R)-14- (6-amino-9H-purin-9-yl)-2,10,16-trihydroxy- 2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one(Diastereomer 1) 
                 691 [M + H] +   
               
               
                   
               
               
                  85 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15aS,16R)-14- (6-amino-9H-purin-9-yl)-2,10,16-trihydroxy- 2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 691 [M + H] +   
               
               
                   
               
               
                  86 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(2R,5S,7R,8R,10R, 12aR,14R,15R,15aS)-14-(6-amino-9H-purin-9- yl)-2,10,15-trihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 689 
               
               
                   
               
               
                  87 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10,15-trihydroxy- 2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 689 
               
               
                   
               
               
                  88 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10,15-trihydroxy- 2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 689 
               
               
                   
               
               
                  89 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(2R,5R,7R,8R,10,R, 12aR,14R,15S,15aR,16R)-14-(6-amino-9H- purin-9-yl)-15-fluoro-2,10,16-trihydroxy-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one(Diastereomer 1) 
                 707 
               
               
                   
               
               
                  90 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15-fluoro-2,10,16- trihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 707 
               
               
                   
               
               
                  91 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15-fluoro-2,10,16- trihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 707 
               
               
                   
               
               
                  92 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15-fluoro-2,10,16- trihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 4) 
                 707 
               
               
                   
               
               
                  93 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-2,10,18-trihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro [3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7(12H)-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 717 
               
               
                   
               
               
                  94 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-2,10,18-trihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 717 
               
               
                   
               
               
                  95 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-2,10,18-trihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 719 [M + H] +   
               
               
                   
               
               
                  96 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15-fluoro-16-hydroxy- 2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 723 
               
               
                   
               
               
                  97 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(2R,5R,7R,8R,10R, 12aR,14R,15S,15aR,16S)-14-(6-amino-9H- purin-9-yl)-15-fluoro-16-hydroxy-2,10-dioxido- 2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 723 
               
               
                   
               
               
                  98 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15-fluoro-16-hydroxy- 2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 723 
               
               
                   
               
               
                  99 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15-fluoro-16-hydroxy- 2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 4) 
                 723 
               
               
                   
               
               
                 100 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6- amino-9H-purin-9-yl)-2,10,18-trihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7(12H)-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 733 
               
               
                   
               
               
                 101 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6- amino-9H-purin-9-yl)-2,10,18-trihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclo- tetradecin-7(12H)-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 733 
               
               
                   
               
               
                 102 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6- amino-9H-purin-9-yl)-2,10,18-trihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7(12H)-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
                 733 
               
               
                   
               
               
                 103 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,16S)-14-(6- amino-9H-purin-9-yl)-12a-ethynyl-16-fluoro- 2,10,15-trihydroxy-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 731 
               
               
                   
               
               
                 104 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,16S)-14-(6- amino-9H-purin-9-yl)-12a-ethynyl-16-fluoro- 2,10,15-trihydroxy-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 731 
               
               
                   
               
               
                 105 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,16S)-14-(6- amino-9H-purin-9-yl)-12a-ethynyl-16-fluoro- 2,10,15-trihydroxy-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 731 
               
               
                   
               
               
                 106 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,16R)-14-(6- amino-9H-purin-9-yl)-12a-ethynyl-16-fluoro- 2,10,15-trihydroxy-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 731 
               
               
                   
               
               
                 107 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,16R)-14-(6- amino-9H-purin-9-yl)-12a-ethynyl-16-fluoro- 2,10,15-trihydroxy-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 731 
               
               
                   
               
               
                 108 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- hydroxy-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 1) 
                 706 
               
               
                   
               
               
                 109 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- hydroxy-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 2) 
                 706 
               
               
                   
               
               
                 110 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- hydroxy-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 3) 
                 706 
               
               
                   
               
               
                 111 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-16- hydroxy-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 1) 
                 706 
               
               
                   
               
               
                 112 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-16- hydroxy-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 2) 
                 706 
               
               
                   
               
               
                 113 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-16- hydroxy-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 3) 
                 706 
               
               
                   
               
               
                 114 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-16- hydroxy-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 4) 
                 706 
               
               
                   
               
               
                 115 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15-fluoro-16-hydroxy-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro- 7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1) 
                 725 
               
               
                   
               
               
                 116 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15-fluoro-16-hydroxy-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro- 7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 725 
               
               
                   
               
            
           
         
       
     
     Examples 117 and 118: 2-amino-9-[(2R,5R,7R,8S,10R,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) and 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
     
       
         
         
             
             
         
       
     
     Step 1: 2R,3S,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphanyl) oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     ((2R,3 S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy) methyl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (1058 mg, 1.234 mmol) was co-evaporated with dry ACN (3×5 mL), re-dissolved in ACN (10 mL) under Ar, and dried by adding activated 4 Å molecular sieve (200 mg). (2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (430 mg, 1.03 mmol) and pyridinium 2,2,2-trifluoroacetate (298 mg, 1.54 mmol) were co-evaporated with ACN (3×5 mL) and then re-dissolved in ACN (10 mL), and dried by adding activated 4 Å molecular sieve (200 mg). After 30 min, it was added to the previously prepared mixture containing ((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl) methoxy)methyl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite. It was stirred at rt for 30 min. The reaction mixture was used for the next reaction step without purification. LCMS (ES, m/z): 1173.8 [M−H] − . 
     Step 2. (2R,3S,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from Step 1 was added (E)-N,N-dimethyl-N-(3-thioxo-3H-1,2,4-dithiazol-5-yl)formimidamide (DDTT, 0.232 g, 1.13 mmol) in one portion. The mixture was stirred at rt for 1 h. It was concentrated to give a crude sample containing the product, which was used for the next reaction step without purification. LCMS (ES, m/z): 1205.8 [M−H] − . 
     Step 3. (2R,3S,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of the crude from Step 2 in CH 2 Cl 2  (15 mL) was added water (0.2 mL, 10 mmol) and 2,2-dichloroacetic acid in CH 2 Cl 2  (0.6M, 15 mL, 9 mmol). After 30 min, triethylsilane (28 mL) was added, and it was stirred for 1.5 h. Then, pyridine (1.4 mL) was added. It was concentrated, and the residue was purified by reverse phase (C18) chromatography eluted with 0 to 43% ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 905.8 [M+H] + .  1 H-NMR (300 MHz, CD 3 OD): δ 8.71-8.44 (m, 2H), 8.21-8.03 (m, 3H), 7.80 (d, J=10.4 Hz, 0.5H), 7.66-7.61 (m, 1H), 7.54 (t, J=7.6 Hz, 2H), 6.61-6.42 (m, 1H), 6.14 (dd, J=13.2, 6.0 Hz, 1H), 5.68 (d, J=9.9 Hz, 0.5H), 5.60-5.19 (m, 3H), 4.69-4.36 (m, 3H), 4.36-4.17 (m, 3H), 3.92-3.64 (m, 2H), 3.13-2.55 (m, 5H), 1.19 (dd, J=6.9, 2.1 Hz, 6H).  19 F-NMR (282 MHz, CD 3 OD): δ −202.55, −202.75 (d, 1F).  31 P-NMR (121 MHz, CD 3 OD): δ 66.91, 66.69 (2s, 1P); 2.66, 2.60 (2s, 1P). 
     Step 4: (5R,7R,8S,12aR,14R,15aS,16R)-2-(2-cyanoethoxy)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2-sulfide 
     
       
         
         
             
             
         
       
     
     Diphenyl phosphorochloridate (2375 mg, 8.84 mmol) was added to pyridine (45 ml) at −30° C. To the solution at −30° C. was added (2R,3S,4R,5R)-5-((((((2R,3S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl) oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (400 mg, 0.44 mmol) in CH 2 Cl 2  (45 mL) dropwise over 20 min. The resulting mixture was stirred at −30° C. for 40 min. The reaction mixture was used for the next reaction step immediately without purification. LCMS (ES, m/z): 887.8 [M+H] + . 
     Step 5: (5R,7R,8S,12aR,14R,15aS,16R)-2-(2-cyanoethoxy)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2,10-disulfide 
     
       
         
         
             
             
         
       
     
     To the mixture from Step 4 at −30° C. was added 3H-benzo[c][1,2]dithiol-3-one (112 mg, 0.663 mmol) and water (279 μL, 15.5 mmol). After stirring at rt for 1 h, the mixture was poured into a solution of Na 2 S 2 O 3 .5H 2 O (280 mg) in water (10 mL) at 0° C. It was stirred at rt for 5 min, and the mixture was concentrated under reduced pressure. The residue was purified by reverse phase (C18) chromatography eluted with 0 to 28% ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 919.8 [M+H] + .  19 F-NMR (376 MHz, CD 3 OD): δ −198.51, −198.98, −200.16 (3s, 1F) + .  31 P-NMR (162 MHz, CD 3 OD): δ 65.90, 65.09, 63.64, 62.95, 57.26, 56.50 (6s, 2P). 
     Step 6. Diastereomers (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl) amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-A), (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-B), and (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-C) 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     To a solution of (5R,7R,8 S,12aR,14R,15aS,16R)-2-(2-cyanoethoxy)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2,10-disulfide (265 mg, 0.288 mmol) in ACN (5 mL) at rt was added tert-butylamine (5 mL, 0.29 mmol). The reaction mixture was stirred for 10 min. Then, volatile components were removed under reduced pressure. The residue was purified by preparative-HPLC (T3 Prep Column, 19 mm×250 mm) eluted with 5 to 20% ACN in aq NH 4 HCO 3  (50 mM) over 21 min. 
     The first fractions (T R : 8.95 min) gave (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-A). LCMS (ES, m/z): 866.7 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 8.74 (s, 1H), 8.71 (s, 1H), 8.26 (s, 1H), 8.07 (d, J=7.5 Hz, 1H), 7.65 (d, J=7.7 Hz, 1H), 7.57 (t, J=7.5 Hz, 2H), 6.60-6.34 (m, 1H), 5.94 (d, J=8.6 Hz, 1H), 5.91-5.66 (m, 1H), 5.46-5.16 (m, 2H), 4.50 (d, J=27.0 Hz, 1H), 4.27 (d, J=9.8 Hz, 1H), 4.16 (t, J=10.1 Hz, 1H), 3.98 (q, J=11.0 Hz, 1H), 3.86 (d, J=11.9 Hz, 1H), 3.72-3.69 (m, 1H), 3.10-3.06 (m, 1H), 3.00-2.82 (m, 1H), 2.74-2.70 (m, 1H), 1.06 (dd, J=27.2, 6.8 Hz, 6H).  31 P-NMR (162 MHz, DMSO-d 6 ): δ 53.92 (s, 1P), 52.99 (s, 1P). 
     The second fractions (T R : 10.00 min) gave (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl) amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-B). LCMS (ES, m/z): 866.7 [M+H] + . 
     The third fractions (T R : 11.27-12.16 min) gave (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-C), a mixture of two diastereomers, which was used in next step. LCMS (ES, m/z): 866.7 [M+H] + .  1 H-NMR (400 MHz, DMSO-d 6 ): δ 8.77 (s, 1H), 8.74 (s, 1H), 8.72 (s, 1H), 8.12-8.02 (m, 2H), 7.66-7.64 (m, 1H), 7.56 (t, J=7.5 Hz, 2H), 6.47-6.44 (m, 1H), 5.99 (d, J=8.6 Hz, 1H), 5.55-5.33 (m, 2H), 5.22 (d, J=11.6 Hz, 1H), 4.47 (d, J=25.7 Hz, 1H), 4.43-4.40 (m, 1H), 4.03-3.98 (m, 2H), 3.84 (d, J=11.8 Hz, 1H), 3.75-3.72 (m, 1H), 3.18-3.15 (m, 1H), 2.82-2.73 (m, 2H), 1.13 (dd, J=6.9, 2.5 Hz, 6H).  31 P-NMR (162 MHz, DMSO): δ 53.42 (s, 1P), 52.16 (s, 1P). 
     Step 7: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1 and 2) 
     
       
         
         
             
             
         
       
     
     (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-C) (180 mg, 0.208 mmol) was dissolved in a solution of MeNH 2  in EtOH (30%, 5.0 mL, 42 mmol), and the resulting solution was stirred at rt for 1 h. The volatile components were removed under reduced pressure to give a crude sample that was purified by Prep-HPLC (Atlantis Prep T3 OBD Column, 19 mm×250 mm) eluted with 5 to 19.5% ACN in aq NH 4 HCO 3  (50 mM) over 19 min to give, after concentration: 
     Example 117 (T R : 14.82 min): 2-amino-9-[(2R,5R,7R,8S,10R,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1). LCMS (ES, m/z): 690.8 [M−H] − .  1 H-NMR (400 MHz, D 2 O): δ 8.14 (s, 1H), 8.13 (s, 1H), 8.11 (s, 1H), 6.37 (t, J=5.5 Hz, 1H), 5.99 (d, J=8.7 Hz, 1H), 5.54 (d, J=3.3 Hz, 0.5H), 5.48-5.30 (m, 1.5H), 5.12 (dd, J=10.2, 5.5 Hz, 1H), 4.66 (d, J=34.1 Hz, 1H), 4.36 (s, 1H), 4.24-4.01 (m, 4H), 3.04 (dt, J=14.1, 5.6 Hz, 1H), 2.79 (dt, J=13.5, 6.4 Hz, 1H).  19 F-NMR (376 MHz, D 2 O): δ −198.66 (s, 1F).  31 P-NMR (162 MHz, D 2 O): δ 53.97 (s, 1P), 53.46 (s, 1P). 
     Example 118 (T R : 15.93 min): 2-amino-9-[(5R,7R,8 S,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2). LCMS (ES, m/z): 690.8 [M−H] − .  1 H-NMR (400 MHz, D 2 O): δ 8.16 (s, 1H), 8.11 (s, 1H), 7.83 (s, 1H), 6.34 (dd, J=6.5, 3.0 Hz, 1H), 5.95 (d, J=8.6 Hz, 1H), 5.69-5.53 (m, 1H), 5.47 (d, J=3.4 Hz, 0.5H), 5.33 (d, J=3.4 Hz, 0.5H), 5.23 (p, J=7.3 Hz, 1H), 4.64 (d, J=26.7 Hz, 1H), 4.35 (ddd, J=10.6, 6.9, 3.2 Hz, 1H), 4.31-4.17 (m, 2H), 4.05-3.95 (m, 2H), 2.94-2.85 (m, 1H), 2.74 (dt, J=14.0, 7.2 Hz, 1H).  19 F-NMR (376 MHz, D 2 O): δ −198.74 (s, 1F).  31 P-NMR (162 MHz, D 2 O): δ 55.05 (s, 1P), 52.87 (s, 1P). 
     Example 119: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12 H -5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
     
       
         
         
             
             
         
       
     
     Step 1: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     (5R,7R,8 S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-B) (45 mg, 0.053 mmol) was dissolved in a solution of MeNH 2  in EtOH (30%, 1.5 mL, 11 mmol), and the resulting solution was stirred at rt for 1 h. The volatile components were removed under reduced pressure, and the residue was purified by Prep-HPLC (Atlantis Prep T3 OBD Column, 19 mm×250 mm) eluted with 18 to 19.5% ACN in aq NH 4 HCO 3  (50 mM) over 16 min to give the product (T R : 11.22 min). LCMS (ES, m/z): 690.8 [M−H] − .  1 H-NMR (400 MHz, D 2 O): δ 8.32 (s, 1H), 8.15 (s, 1H), 7.96 (s, 1H), 6.41 (t, J=5.7 Hz, 1H), 6.00 (d, J=8.6 Hz, 1H), 5.56 (dt, J=22.9, 10.4 Hz, 1H), 5.40-5.30 (m, 1.5H), 5.19 (d, J=3.6 Hz, 0.5H), 4.64 (d, J=28.3 Hz, 1H), 4.40-4.27 (m, 2H), 4.27-4.17 (m, 1H), 4.02 (d, J=11.9 Hz, 1H), 3.95-3.85 (m, 1H), 2.92 (dt, J=14.1, 5.6 Hz, 1H), 2.79 (td, J=13.8, 13.1, 6.1 Hz, 1H).  19 F-NMR (376 MHz, D 2 O): δ −198.02 (s, 1F).  31 P-NMR (162 MHz, D 2 O): δ 57.89 (s, 1P), 55.05 (s, 1P). 
     Example 120: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12 H -5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 4) 
     
       
         
         
             
             
         
       
     
     Step 1: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(6-amino-9H-purin-9-yl)-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     (5R,7R,8S,12aR,14R,15aS,16R)-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-diolate 2,10-disulfide (28-6-A) (45 mg, 0.053 mmol) was dissolved in a solution of MeNH 2  in EtOH (30%, 1.5 mL, 11 mmol), and the resulting solution was stirred at rt for 1 h. The volatile components were removed under reduced pressure, and the residue was purified by Prep-HPLC (Atlantis Prep T3 OBD Column, 19 mm×250 mm) eluted with 4 to 11% ACN in aq NH 4 HCO 3  (50 mM) over 17 min to give the product (T R : 11.72 min). LCMS (ES, m/z): 690.8 [M−H] − .  1 H-NMR (400 MHz, D 2 O): δ 8.33 (s, 1H), 8.29 (s, 1H), 8.16 (s, 1H), 6.41 (t, J=6.5 Hz, 1H), 6.05 (d, J=8.6 Hz, 1H), 5.49-5.32 (m, 1.5H), 5.23 (d, J=3.5 Hz, 0.5H), 4.79-4.73 (m, 1H), 4.69-4.59 (m, 1H), 4.40-4.32 (m, 1H), 4.23 (q, J=8.9, 7.5 Hz, 2H), 4.07 (d, J=11.8 Hz, 1H), 3.94-3.84 (m, 1H), 3.00 (dt, J=12.7, 6.2 Hz, 1H), 2.94-2.84 (m, 1H).  19 F-NMR (376 MHz, D 2 O): δ −197.92 (s, 1F).  31 P-NMR (162 MHz, D 2 O): δ 59.46 (s, 1P), 54.42 (s, 1P). 
     Example 121, 122, 123: 2-amino-9-[(2R,5S,7R,8R,10R,12aR,14R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) and 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 2 and 3) 
     
       
         
         
             
             
         
       
     
     Step 1. (2R,3R,5S)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate 
     
       
         
         
             
             
         
       
     
     To a flask was added (2R,3R,5 S)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (4 g, 4.76 mmol), MeCN (23.65 ml), and water (0.158 ml). Pyridine trifluoroacetate (1.104 g, 5.71 mmol) was then added, and the mixture was stirred 1 h at rt, after which time tert-butylamine (20.02 ml, 190 mmol) was added. After stirring 1 h at rt, the mixture was concentrated under reduced pressure. The resulting mixture was dissolved in DCM (39.9 ml), and then water (0.798 ml) was added, followed by dichloroacetic acid (2.75 ml, 33.3 mmol). The solution was stirred for 20 min at rt, and then triethylsilane (133 ml, 833 mmol) was added, and the reaction was stirred for a further 2 h at rt. After cooling to 0° C., pyridine was added, and the mixture was concentrated under reduced pressure. The resulting sample was partitioned between hexanes (100 mL) and water (20 mL). The layers were separated, and the aqueous phase was purified by reverse phase HPLC using a gradient solvent system of 0-35% MeCN in 0.04% aq ammonium bicarbonate. The product-containing fractions were collected and lyophilized to give (2R,3R,5S)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate. LCMS (ES, m/z): 400 [M−H] − . 
     Step 2: (2R,3S,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl) (phenyl)methoxy)methyl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite 
     
       
         
         
             
             
         
       
     
     To a flask was added N-(7-((2R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy) methyl)-4-hydroxytetrahydrofuran-2-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)benzamide (4 g, 6.09 mmol), DCM (71.7 ml), and 4,5-dicyanoimidazole (2.158 g, 18.27 mmol), and the solution was cooled to 0° C. 2-Cyanoethyl N,N,N′,N′-tetraisopropylphosphorodiamidite (6.77 ml, 21.32 mmol) was added, and the mixture was stirred for 15 min at 0° C., after which time the mixture was concentrated under reduced pressure and purified by silica gel chromatography using a gradient of 30-100% EtOAc in hexanes to yield (2R,3S,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite. LCMS (ES, m/z): 857 [M+H] − . 
     Step 3: (2R,3R,5S)-5-((((((2R,3S,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate 
     
       
         
         
             
             
         
       
     
     To a flask containing (2R,3R,5S)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate (1.62 g, 2.81 mmol) was added pyridine trifluoroacetate (0.543 g, 2.81 mmol), activated 4 Å sieves and MeCN (10 mL), and the mixture was stirred 20 min at rt. To a separate flask containing (2R,3S,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl) tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (2.408 g, 2.81 mmol) was added MeCN (10 mL) and activated 4 Å sieves, and the mixture was stirred 20 min at rt, after which time the hydrogen phosphonate solution was added, and MeCN (2×4 mL) was used to complete the transfer. The mixture was stirred 1 h at rt, and then ((dimethylamino-methylidene)amino)-3H-1,2,4-dithiazoline-3-thione (0.634 g, 3.09 mmol) was added. The resulting mixture was stirred 30 min at rt and then concentrated under reduced pressure. Reverse phase HPLC purification using a gradient solvent system of 5-100% MeCN in 0.04% aqueous ammonium bicarbonate yielded (2R,3R,5S)-5-((((((2R,3S,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy) phosphorothioyl)oxy)methyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate. LCMS (ES, m/z): 1187 [M−H] − . 
     Step 4: N-{7-[(5S,7R,8R,12aR,14R,15aS)-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-10-oxido-10-sulfanyl-2-sulfidooctahydro-12H-5,8-methanofuro 3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide 
     
       
         
         
             
             
         
       
     
     To a flask containing (2R,3R,5 S)-5-((((((2R,3 S,5R)-5-(4-benzamido-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-2-(2-isobutyramido-6-oxo-1H-purin-9(6H)-yl)tetrahydrofuran-3-yl hydrogen phosphonate (1.34 g, 1.127 mmol) was added DCM (22.54 ml) and water (0.203 ml, 11.27 mmol), and then dichloroacetic acid (1.116 ml, 13.52 mmol) was added. The solution was stirred for 20 min at rt, and then triethylsilane (28.1 ml, 176 mmol) was added. After stirring 3 h at rt, the mixture was concentrated under reduced pressure. Pyridine (50 mL) was added, and then the mixture was concentrated under reduced pressure. This process was repeated 2×, and then pyridine (37.6 ml) was added, followed by 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane 2-oxide (0.624 g, 3.38 mmol). The resulting mixture was stirred for 1 h at rt, after which time water (610l, 33.8 mmol) was added, followed by 3H-1,2-benzodithiol-3-one (285 mg, 1.692 mmol). The resulting mixture was stirred 30 min at rt and then concentrated under reduced pressure. HPLC purification using a gradient solvent system of MeCN in 100 mM aqueous triethylammonium acetate yielded 3 separate diastereomers of N-{7-[(5S,7R,8R,12aR,14R,15aS)-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl})-10-oxido-10-sulfanyl-2-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide after lyopholization, all of which showed LCMS (ES, m/z): 899 [M−H]*. 
     Step 5: 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To a vial containing one diastereomer (slowest eluting) of N-{7-[(5S,7R,8R,12aR,14R,15aS)-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-10-oxido-10-sulfanyl-2-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide (122 mg, 0.135 mmol) was added methylamine (33% in EtOH) (2 mL, 16.07 mmol) and the resulting solution was stirred for 4 h at rt, after which time it was concentrated under reduced pressure. Purification by reverse phase HPLC using a gradient solvent system of MeCN in 100 mM aqueous triethylammonium acetate yielded Example 121, 2-amino-9-[(2R,5S,7R,8R,10R,12aR,14R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1). LCMS (ES, m/z): 672 [M−H] − .  1 H NMR (600 MHz, DMSO-d 6 ) δ 10.54 (s, 1H), 8.01 (s, 1H), 7.86 (s, 1H), 7.29 (d, J=2.7 Hz, 1H), 6.97 (s, 2H), 6.60-6.53 (m, 3H), 6.44 (t, J=6.9 Hz, 1H), 5.73 (d, J=2.7 Hz, 1H), 4.95 (s, 1H), 4.80 (s, 1H), 4.38-4.27 (m, 2H), 3.97-3.91 (m, 2H), 3.90-3.82 (m, 1H), 3.64 (dt, J=16.1, 9.3 Hz, 1H), 2.69-2.63 (m, 1H), 2.63 (s, 12H), 2.60-2.54 (m, 3H), 2.22-2.13 (m, 1H), 1.01-0.94 (m, 18H). 
     The other diastereomers from Step 4 were treated in an analogous manner to produce two additional diastereomers of 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one: 
     Example 122 (Diastereomer 2): LCMS (ES, m/z): 672 [M−H] − .  1 H NMR (600 MHz, DMSO-d 6 ) δ 10.57 (s, 1H), 9.55 (s, 2H), 8.10 (s, 1H), 7.95 (s, 1H), 7.47 (s, 1H), 7.42 (d, J=3.2 Hz, 1H), 6.66 (d, J=3.4 Hz, 1H), 6.51 (s, 2H), 6.49-6.44 (m, 1H), 5.73 (d, J=4.0 Hz, 1H), 5.08-5.00 (m, 2H), 4.31-4.27 (m, 1H), 4.22 (t, J=11.3 Hz, 1H), 4.07 (q, J=10.6 Hz, 1H), 4.00-3.95 (m, 1H), 3.76-3.71 (m, 1H), 3.65 (td, J=11.6, 6.1 Hz, 1H), 3.02 (d, J=4.2 Hz, 12H), 2.67-2.61 (m, 1H), 2.61-2.53 (m, 2H), 2.18 (dt, J=11.7, 5.3 Hz, 1H), 1.12 (t, J=7.3 Hz, 18H). 
     Example 123 (Diastereomer 3): LCMS (ES, m/z): 672 [M−H] − .  1 H NMR (600 MHz, DMSO-d 6 ) δ 10.53 (s, 1H), 8.01 (s, 3H), 7.28 (d, J=3.4 Hz, 1H), 6.97 (s, 2H), 6.56 (d, J=3.5 Hz, 1H), 6.49 (s, 2H), 6.44 (dd, J=8.6, 5.8 Hz, 1H), 5.70 (d, J=3.9 Hz, 1H), 5.00-4.92 (m, 1H), 4.90-4.83 (m, 1H), 4.33-4.27 (m, 1H), 4.12-3.96 (m, 4H), 3.81 (q, J=12.8, 11.6 Hz, 1H), 3.69 (dd, J=12.0, 6.0 Hz, 2H), 2.83-2.77 (m, 1H), 2.65 (d, J=37.6 Hz, 12H), 2.23 (dt, J=12.8, 6.7 Hz, 1H), 1.03-0.92 (m, 18H). 
     Examples 124, 125, and 126: 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-18-fluoro-2,10-dihydroxy-2,10-disulfidohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7(12H)-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1-3) 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phenyl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of N-(9-((2R,3 S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy) methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (630 mg, 0.96 mmol) in pyridine (5 mL) under Ar was added diphenyl phosphonate (1.07 g, 4.56 mmol), and the mixture was stirred at rt for 20 min. It was used for the next reaction step without purification. LCMS (ES, m/z): 798.3 [M+H] + . 
     Step 2: t (2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from Step 1 at 0° C. was added water (1 mL), triethylamine (1 mL). 
     The resulting mixture was stirred at rt for 20 min. Then, it was concentrated, and the residue was partitioned between CH 2 Cl 2  (50 mL) and aq NaHCO 3  (5%, 20 mL). The organic layer was washed with aq NaHCO 3  (5%, 20 mL), dried (Na 2 S 2 O 4 ), concentrated and purified by silica gel column chromatography using 0-7% MeOH in CH 2 Cl 2  (1% Et 3 N) to give the product. LCMS (ES, m/z): 722.2 [M+H] + .  1 H-NMR (400 MHz, CD 3 OD): δ 7.76 (s, 1H), 7.74 (s, 0.5H), 7.51 (d, J=1.5 Hz, 1H), 7.48 (q, J=2.4, 1.9 Hz, 1H), 7.41-7.34 (m, 4H), 7.34-7.27 (m, 2H), 7.26-7.21 (m, 1H), 6.92-6.85 (m, 4H), 6.22 (s, 1H), 6.15 (s, 0.5H), 5.37 (d, J=2.7 Hz, 0.5H), 5.28-5.19 (m, 1.5H), 4.73-4.69 (m, 0.5H), 4.66-4.62 (m, 1H), 3.80 (s, 6H), 3.65-3.55 (m, 1H), 3.53-3.44 (m, 1H), 3.12 (q, J=7.3 Hz, 8H), 2.75 (p, J=6.8 Hz, 1H), 1.33-1.22 (m, 18H).  31 P-NMR: (162 MHz, CD 3 OD): δ 2.67 (s, 1P). 
     Step 3: (2R,3S,4S,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of (2R,3S,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy) methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (540 mg, 0.64 mmol) in CH 2 Cl 2  (7 mL) at rt was added water (0.115 g, 6.4 mmol) and 2,2-dichloroacetic acid in CH 2 Cl 2  (6%, 7 mL, 5.76 mmol). The mixture was stirred at rt for 15 min, and then Et 3 SiH (15 mL) was added. After 40 min, pyridine (0.90 mL) was added, and the mixture was stirred for 5 min. It was concentrated, and the residue was used for next reaction step without purification. LCMS (ES, m/z): 419.9 [M+H] + . 
     Step 4. (2R,3S,4S,5R)-5-((((((1R,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     The crude from Step 3 was co-evaporated with ACN (3×5 mL), re-dissolved in ACN (3 mL) under Ar, and dried by adding activated 4 Å molecular sieve (100 mg). (1R,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl (2-cyanoethyl) diisopropylphosphoramidite (684.84 mg, 0.774 mmol) was co-evaporated with ACN (3×5 mL), re-dissolved in ACN (3 mL), and dried by adding activated 4 Å molecular sieve (100 mg). After 30 min, it was added to the previously prepared mixture containing pyridin-1-ium (2R,3 S,4S,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate. The resulting mixture was stirred at rt for 30 min. Then it was used in the next reaction step without purification. LCMS (ES, m/z): 1202.1 [M+H] + . 
     Step 5. (2R,3S,4S,5R)-5-((((((1R,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the mixture from Step 4 was added (E)-N,N-dimethyl-N′(3-thioxo-3H-1,2,4-dithiazol-5-yl)formimidamide (144.32 mg, 0.704 mmol), and the mixture was stirred at rt for 30 min. Then, it was concentrated, and the crude was used for the next step without purification. LCMS (ES, m/z): 1234.3 [M+H] + . 
     Step 6. (2R,3S,4S,5R)-5-((((((1S,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-(hydroxymethyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of the crude from Step 5 in CH 2 Cl 2  (7 mL) at rt was added water (120 mg, 6.4 mmol) and 2,2-dichloroacetic acid in CH 2 Cl 2  (6%, 7 mL, 6 mmol). After 5 min, triethylsilane (15 mL) was added, and it was stirred for additional 2 h. Then, pyridine (0.9 mL) was added, and it was concentrated. The residue was purified by reverse phase (C18) chromatography eluted with 0 to 95% ACN in aq NH 4 HCO 3  (0.04%) to give the product. LCMS (ES, m/z): 933.9 [M+H] + .  1 H-NMR (400 MHz, CD 3 OD): δ 8.74-8.64 (m, 1H), 8.58-8.52 (m, 1H), 8.16-8.06 (m, 2H), 7.98-7.88 (m, 1H), 7.75 (d, J=4.6 Hz, 0.5H), 7.67 (t, J=7.3 Hz, 1H), 7.60-7.56 (m, 2H), 6.25-6.22 (m, 1H), 6.19-6.10 (m, 1H), 5.91 (s, 0.5H), 5.46-5.22 (m, 3H), 5.12 (d, J=12.4 Hz, 1H), 4.84-4.49 (m, 3H), 4.35 (tdd, J=13.2, 6.1, 3.0 Hz, 2H), 4.14 (d, J=8.5 Hz, 1H), 4.11-3.96 (m, 3H), 2.91 (dt, J=16.4, 6.0 Hz, 2H), 2.81-2.68 (m, 1H), 1.29-1.21 (m, 6H).  31 P-NMR: (162 MHz, CD 3 OD): δ 67.84, 66.33 (2 s, 1P); 2.65, 2.52 (2 s, 1P). 
     Step 7: (5R,7R,8S,12aR,14R,15R,15aS,18S)-2-(2-cyanoethoxy)-18-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10 (12H)-olate 2-sulfide 
     
       
         
         
             
             
         
       
     
     To pyridine (30 mL) at −40° C. under Ar was added diphenyl phosphorochloridate (1783.7 mg, 6.64 mmol) and then, a solution of (2R,3 S,4S,5R)-5-((((((1S,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-(hydroxymethyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (310 mg, 0.33 mmol, co-evaporated with pyridine 3×5 mL) in CH 2 Cl 2  (30 mL) over 20 min. The resulting mixture was stirred at −40° C. for 20 min. It was used in the next step immediately without purification. LCMS (ES, m/z): 916.1 [M+H] + . 
     Step 8. (5R,7R,8S,12aR,14R,15R,15aS,18S)-2-(2-cyanoethoxy)-18-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro [3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10(12H)-olate 2,10-disulfide 
     
       
         
         
             
             
         
       
     
     To the solution from Step 7 at −40° C. was added 3H-benzo[c][1,2]dithiol-3-one (83.6 mg, 0.498 mmol) and water (179 mg, 9.92 mmol). The mixture was stirred at rt for 40 min. Then, it was concentrated, and the residue was purified by reverse phase (C18) chromatography eluted with 0 to 95% ACN in aq NH 4 HCO 3  (0.04%) to give the product. LCMS (ES, m/z): 947.8 [M+H] + .  1 H-NMR (400 MHz, CD 3 OD): δ 8.79-8.58 (m, 2H), 8.18-8.06 (m, 2H), 7.92 (d, J=13.5 Hz, 1H), 7.69-7.66 (m, 1H), 7.63-7.54 (m, 2H), 6.40-6.14 (m, 2H), 6.03-5.56 (m, 1.5H), 5.39-5.10 (m, 2.5H), 4.93-4.85 (m, 2H), 4.84-4.43 (m, 3H), 4.43-3.98 (m, 3H), 2.95 (t, J=5.9 Hz, 1H), 2.84-2.66 (m, 2H), 1.30-1.19 (m, 6H).  31 P-NMR (162 MHz, CD 3 OD): δ 66.60-64.98 (m, 1P), 56.95-55.65 (m, 1P). 
     Step 9: 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-18-fluoro-2,10-dihydroxy-2,10-disulfidohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7 (12H)-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomers 13) 
     
       
         
         
             
             
         
       
     
     (5R,7R,8S,12aR,14R,15R,15aS,18 S)-2-(2-cyanoethoxy)-18-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10(12H)-olate 2,10-disulfide (260 mg, 0.27 mmol) was dissolved in a solution of MeNH 2  in EtOH (30%, 20 mL), and the resulting solution was stirred at rt for 3 h. Then, it was concentrated, and the residue was purified by Prep-HPLC (Atlantis Prep RP C18 OBD Column, 19 mm×250 mm) eluted with 0 to 14% ACN in aq NH 4 HCO 3  (50 mM) over 25 min to afford the diastereomers of 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-18-fluoro-2,10-dihydroxy-2,10-disulfidohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7(12H)-yl]-1,9-dihydro-6H-purin-6-one: 
     Example 124 (T R : 22.52 min): LCMS (ES, m/z): 719.0 [M−H] − .  1 H-NMR: (400 MHz, D 2 O+DCl): δ 8.71 (s, 1H), 8.26 (s, 1H), 8.09 (s, 1H), 5.73 (s, 1H), 5.65 (s, 1H), 5.22-5.10 (m, 1H), 4.74-4.72 (m, 2H), 4.45 (d, J=4.1 Hz, 1H), 4.21-4.11 (m, 1H), 4.05-3.94 (m, 2H), 3.83-3.56 (m, 2H), 3.46 (s, 2H).  31 P-NMR: (162 MHz, D 2 O+DCl): δ 60.35 (s, 1P), 56.87 (s, 1P). 
     Example 125 (T R : 15.75 min): LCMS (ES, m/z): 719.0 [M−H] − .  1 H-NMR: (400 MHz, D 2 O): δ 8.31 (s, 1H), 8.14 (s, 1H), 7.74 (s, 1H), 6.11 (s, 1H), 6.06 (s, 1H), 5.61-5.49 (m, 1H), 5.35 (s, 1H), 5.10 (d, J=9.8 Hz, 1H), 4.71-4.55 (m, 1H), 4.51-4.20 (m, 3H), 4.18-3.95 (in, 4H).  3 P-NMR: (162 MHz, D 2 O): δ 54.87-51.81 (m, 2P). 
     Example 126 (T R : 13.17 min): LCMS (ES, m/z): 718.8 [M−H]−.  1 H-NMR: (300 MHz, D 2 O+DCl): δ 8.89 (s, 1H), 8.46 (s, 1H), 8.29 (s, 1H), 5.95 (s, 1H), 5.88 (s, 1H), 5.30-5.14 (m, 1H), 4.98 (t, J=5.2 Hz, 1H), 4.89 (s, 1H), 4.60 (s, 1H), 4.35-4.14 (m, 2H), 4.07 (d, J=11.4 Hz, 1H), 4.01-3.85 (m, 2H), 3.68-3.62 (in, 2H).  3 P-NM/R: (121 MHz, D 2 O+DCl): δ 60.15 (s, 1P), 56.60 (s, 1P). 
     Examples 127 and 128: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1), and 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H1-purin-6-one (Diastereomer 2) 
     
       
         
         
             
             
         
       
     
     Step 1. (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl phenyl phosphonate 
     
       
         
         
             
             
         
       
     
     To a stirred solution of N-(3-2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-3-fluoro-4-hydroxytetrahydrofuran-2-yl)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)benzamide (770 mg, 1.138 mmol) in pyridine (5 ml) at 0° C. under Ar was added diphenyl phosphonate (1.33 g, 5.69 mmol) over 2 min. The resulting mixture was stirred at rt for 20 min. It was used for the next reaction step directly without purification. 
     Step 2: (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from Step 1 at 0° C. was added Et 3 N (0.56 mL) in water (0.56 mL) over 5 min. The resulting mixture was stirred at rt for 30 min. It was concentrated, and the residue was partitioned between CH 2 Cl 2  (60 mL) and aq NaHCO 3  (5%, 24 mL). The organic layer was washed with aq NaHCO 3  (5%, 2×24 mL), dried (Na 2 SO 4 ), concentrated, and purified by chromatography on silica gel using 0-10% MeOH in CH 2 Cl 2  (0.5% Et 3 N) to give the product. LCMS (ES, m/z): 741.2 [M+H] + .  1 H-NMR (400 MHz, CD 3 OD): δ 8.79 (s, 1H), 8.21-8.11 (m, 2H), 7.71 (t, J=7.4 Hz, 1H), 7.67-7.58 (m, 2.5H), 7.46-7.37 (m, 2H), 7.30-7.23 (m, 4H), 7.18-7.13 (m, 2H), 7.03 (dd, J=6.4, 2.8 Hz, 1H), 6.76-6.73 (m, 2H), 6.69-6.65 (m, 2H), 6.04 (s, 0.5H), 5.85 (t, J=6.4 Hz, 0.5H), 5.72 (t, J=6.4 Hz, 0.5H), 5.60 (td, J=16.9, 6.9 Hz, 1H), 4.44-4.40 (m, 1H), 3.77-3.68 (m, 8H), 3.57 (dd, J=10.6, 2.9 Hz, 1H), 2.91 (q, J=7.3 Hz, 18H), 1.20 (t, J=7.3 Hz, 27H).  31 P-NMR: (162 MHz, CD 3 OD): δ 2.48 (s, 1P). 
     Step 3: (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate (610 mg, 0.65 mmol) in CH 2 Cl 2  (9.8 mL) was added water (0.12 g, 6.5 mmol) and dichloroacetic acid in CH 2 Cl 2  (0.6M, 9.8 mL, 5.9 mmol). After 30 in, triethylsilane (20 mL) was added and stirring was continued for additional 2 h. Then, pyridine (5 mL) was added, and it was concentrated. The crude was used for the next reaction step without purification. LCMS (ES, m/z): 439.1 [M+H] + . 
     Step 4: (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((((2-cyanoethoxy)(((2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)oxy)phosphanyl)oxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     The crude product of Step 3 was co-evaporated with dry ACN (3×3 mL), re-dissolved in ACN (3 mL), and dried by adding activated 4 Å molecular sieve (200 mg). (2R,3 S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (0.824 g, 0.960 mmol) was co-evaporated with dry ACN (3×3 mL), re-dissolved in ACN (5 mL), and dried by adding activated 4 Å molecular sieve (200 mg). After 30 min, it was added to the previously prepared mixture containing pyridin-1-ium (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl phosphonate. It was stirred at rt for 30 min, and the reaction mixture was used in the next reaction step directly without purification. LCMS (ES, m/z): 893.2 [M+H] + . 
     Step 5: Diastereomers (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((((2-cyanoethoxy)(((2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)oxy)phosphorothioyl)oxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate (116-5-A) and (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((((2-cyanoethoxy)(((2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)oxy)phosphorothioyl)oxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate (116-5-B) 
     
       
         
         
             
             
         
       
     
     To the reaction mixture from Step 4 at rt, was added (E)-N,N-dimethyl-N′-(3-thioxo-3H-1,2,4-dithiazol-5-yl)formimidamide (181 mg, 0.880 mmol), and the mixture was stirred for 1 h. Then, it was concentrated, and the residue was purified by reverse phase (AQ-C18) chromatography eluted with 0 to 28% ACN in aq NH 4 HCO 3  (5 mM) over 88 min. 
     The first fractions with desired mass (T R =50 min) gave (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((((2-cyanoethoxy)(((2R,3 S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)oxy)phosphorothioyl)oxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate (116-5-A). LCMS (ES, m/z): 924.9 [M+H] + .  1 H-NMR: (400 MHz, CD 3 OD): δ 8.90 (s, 1H), 8.31 (s, 1H), 8.10 (d, J=7.8 Hz, 2H), 7.75 (s, 0.5H), 7.69 (t, J=7.4 Hz, 1H), 7.57 (t, J=7.7 Hz, 2H), 7.02 (dd, J=6.5, 2.6 Hz, 1H), 6.27-6.13 (m, 1.5H), 5.79-5.51 (m, 3H), 5.47-5.21 (m, 12H), 4.58 (dd, J=15.4, 7.6 Hz, 2H), 4.50-4.25 (m, 3H), 4.05 (ddd, J=24.7, 13.2, 6.1 Hz, 2H), 3.90-3.76 (m, 4H), 2.85-2.56 (m, 3H), 1.34 (d, J=6.5 Hz, 3H), 1.25-1.19 (m, 3H).  31 P-NMR (162 MHz, CD 3 OD): δ 67.56 (s, 1P), 3.09 (s, 1P). 
     The second fractions with desired mass (T R =55 min) gave (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((((2-cyanoethoxy)(((2R,3 S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)oxy)phosphorothioyl)oxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate (116-5-B). LCMS (ES, m/z): 925.1 [M+H] + .  1 H-NMR: (400 MHz, CD 3 OD): δ 8.87 (s, 1H), 8.33 (s, 1H), 8.16 (d, J=7.8 Hz, 2H), 7.75 (s, 0.5H), 7.70 (t, J=7.4 Hz, 1H), 7.61 (t, J=7.7 Hz, 2H), 6.91 (dd, J=6.2, 3.4 Hz, 1H), 6.23 (d, J=7.1 Hz, 1H), 6.17 (s, 0.5H), 5.74-5.54 (m, 3H), 5.46 (d, J=4.6 Hz, 0.5H), 5.33 (d, J=4.6 Hz, 0.5H), 4.65-4.24 (m, 4H), 4.15 (dt, J=13.0, 5.8 Hz, 2H), 3.95-3.75 (m, 2H), 2.90-2.67 (m, 3H), 1.36-1.31 (m, 3H), 1.19 (d, J=6.8 Hz, 3H).  31 P-NMR: (162 MHz, CD 3 OD): δ 67.29 (s, 1P), 3.07 (s, 1P). 
     Step 6: (5R,7R,8S,12aR,14R,15S,15aR,16R)-10-(2-cyanoethoxy)-15,16-difluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{7-[(phenylcarbonyl)amino]-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-2-olate 10-sulfide 
     
       
         
         
             
             
         
       
     
     To pyridine (10 mL) at −40° C. under Ar was added diphenyl phosphorochloridate (628 mg, 2.34 mmol), and then, a solution of (2R,3R,4S,5R)-5-(7-benzamido-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-2-((((2-cyanoethoxy)(((2R,3 S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)oxy)phosphorothioyl)-oxy)methyl)-4-fluorotetrahydrofuran-3-yl phosphonate (116-5-B) (110 mg, 0.105 mmol, co-evaporated with pyridine 3×5 mL) in CH 2 Cl 2  (10 mL) over 20 min. It was stirred at −40° C. for 20 min. The reaction mixture was used in the next step immediately without purification. 
     Step 7: (5R,7R,8S,12aR,14R,15S,15aR,16R)-10-(2-cyanoethoxy)-15,16-difluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{7-[(phenylcarbonyl)amino]-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-2-olate 2,10-disulfide 
     
       
         
         
             
             
         
       
     
     To the mixture from Step 6 at −20° C. was added 3H-benzo[c][1,2]dithiol-3-one (27.8 mg, 0.165 mmol) and water (42 mg, 2.3 mmol). The resulting mixture was stirred at rt for 30 min. It was concentrated, and the residue was purified by reverse phase (AQ-C18) chromatography eluted with 0 to 28% ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 938.9 [M+H] + .  1 H-NMR: (400 MHz, CD 3 OD): δ 8.94-8.71 (m, 2H), 8.23-8.06 (m, 2H), 7.75-7.67 (m, 1H), 7.64 (t, J=7.5 Hz, 2H), 7.11-6.97 (m, 1H), 6.32-6.17 (m, 2H), 6.02-5.73 (m, 2H), 5.68-5.38 (m, 1H), 4.73 (d, J=24.3 Hz, 1H), 4.68-4.42 (m, 4H), 4.39-4.19 (m, 2H), 4.06-3.66 (m, 2H), 2.99-2.62 (m, 2H), 2.61-2.37 (m, 1H), 1.20 (d, J=6.8 Hz, 3H), 1.12 (d, J=6.7 Hz, 3H).  31 P-NMR: (162 MHz, CD 3 OD): δ 64.05, 63.79 (2 s, 1P); 56.67, 56.27 (2 s, 1P). 
     Step 8: 2-amino-9-(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7-amino-3H-[1, 2,3]triazolo[4,5-d]pyrimidin-3-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1 and 2) 
     
       
         
         
             
             
         
       
     
     To pyridinium (5R,7R,8S,12aR,14R,15S,15aR,16R)-10-(2-cyanoethoxy)-15,16-difluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{7-[(phenylcarbonyl) amino]-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-2-olate 2,10-disulfide in a steel tank (150 mL) at −60° C. was added ammonia in isopropanol (50 mL) at −60° C. The reactor was tightly sealed and then, heated at 50° C. for 16 h. Then, the volatile components were removed under reduced pressure, and the residue was purified by prep-HPLC (Atlantis Prep T3 OBD Column, 19×250 mm) eluted with 0 to 5% ACN in aq NH 4 HCO 3  (50 mM) over 25 min. 
     Example 127 (T R =17.32 min): 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1). LCMS (ES, m/z): 709.8 [M−H] − .  1 H-NMR: (400 MHz, D 2 O): δ 8.32 (s, 1H), 8.27 (s, 1H), 6.78 (dd, J=11.1, 4.9 Hz, 1H), 6.07 (d, J=8.6 Hz, 1H), 5.81 (t, J=4.6 Hz, 0.5H), 5.68 (t, J=4.7 Hz, 0.5H), 5.63 (dq, J=9.8, 5.0 Hz, 1H), 5.58 (d, J=3.5 Hz, 0.5H), 5.45 (d, J=3.4 Hz, 0.5H), 5.43-5.26 (m, 1H), 4.65-4.63 (m, 1H), 4.56 (q, J=5.6 Hz, 1H), 4.31-4.23 (m, 3H), 4.12-4.05 (m, 1H).  31 P-NMR: (162 MHz, D 2 O): δ 55.76 (s, 1P), 54.26 (s, 1P). 
     Example 128 (T R =21.10 min): 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2). LCMS (ES, m/z): 709.8 [M−H] − .  1 H-NMR: (400 MHz, D 2 O): δ 8.26 (s, 1H), 8.01 (s, 1H), 6.79 (dd, J=9.4, 5.3 Hz, 1H), 6.05 (d, J=8.6 Hz, 1H), 5.85 (t, J=5.0 Hz, 0.5H), 5.72 (t, J=5.0 Hz, 0.5H), 5.65-5.35 (m, 3H), 4.69-4.62 (m, 1H), 4.48 (d, J=5.5 Hz, 1H), 4.42 (t, J=11.1 Hz, 1H), 4.18 (t, J=6.2 Hz, 2H), 4.09-4.06 (m, 1H).  31 P-NMR (162 MHz, D 2 O): δ 54.74 (s, 1P), 53.84 (s, 1P). 
     Examples 129 through 243, as shown in Table 6 below, were or may be prepared according to procedures analogous to those outlined in Examples 116 through 128 above using the appropriate monomers, described as Preparations or as obtained from commercial sources, in the coupling step. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 6 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                 129 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetra- decin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
                 710 
               
               
                   
               
               
                 130 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(2R,5S,7R,8R,10R,12aR,14R,15S,15aR)-14-(6- amino-9H-purin-9-yl)-15-fluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 691 
               
               
                   
               
               
                 131 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)- 14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 691 
               
               
                   
               
               
                 132 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)- 14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-oe (Diastereomer 3) 
                 691 
               
               
                   
               
               
                 133 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15-fluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 694 
               
               
                   
               
               
                 134 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 719 
               
               
                   
               
               
                 135 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 719 
               
               
                   
               
               
                 136 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 719 
               
               
                   
               
               
                 137 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 4) 
                 719 
               
               
                   
               
               
                 138 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 692 
               
               
                   
               
               
                 139 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dioxido-2,10- disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 701 
               
               
                   
               
               
                 140 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (6-amino-9H-purin-9-yl)-2,10-dioxido-2,10- disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 701 
               
               
                   
               
               
                 141 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dioxido-2,10- disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diasteroemer 3) 
                 701 
               
               
                   
               
               
                 142 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dioxido-2,10- disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 4) 
                 701 
               
               
                   
               
               
                 143 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-10-oxido-2-sulfidooctahydro-12H- 5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 694 
               
               
                   
               
               
                 144 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(2R,5R,7R,8S,10R,12aR,14R,15S,15aR,16S)- 14-(6-amino-9H-purin-9-yl)-15,16-difluoro- 2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 709 
               
               
                   
               
               
                 145 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 709 
               
               
                   
               
               
                 146 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 709 
               
               
                   
               
               
                 147 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetra- decin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 710 
               
               
                   
               
               
                 148 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetra- decin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 710 
               
               
                   
               
               
                 149 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4- aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 673 
               
               
                   
               
               
                 150 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4- aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 673 
               
               
                   
               
               
                 151 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(2R,5S,7R,8R,10R, 12aR,14R,15aS)-14-(4-aminoimidazo[2,1- f][1,2,4]triazin-7-yl)-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 673 
               
               
                   
               
               
                 152 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4- aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 4) 
                 673 
               
               
                   
               
               
                 153 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15S,15aR,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6- amino-9H-purin-9-yl)-15,16-difluorooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecine-2,10-bis(thiolate) 2,10- dioxide (Diastereomer 1) 
                 725 
               
               
                   
               
               
                 154 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 (5R,7R,8R,12aR,14R,15S,15aR,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6- amino-9H-purin-9-yl)-15,16-difluorooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecine-2,10-bis(thiolate) 2,10-dioxide (Diastereomer 2) 
                 725 
               
               
                   
               
               
                 155 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR)-14- (6-amino-9H-purin-9-yl)-15,16,16-trifluoro- 2,10-dihydroxy-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 727 
               
               
                   
               
               
                 156 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR)-14- (6-amino-9H-purin-9-yl)-15,16,16-trifluoro- 2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 727 
               
               
                   
               
               
                 157 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-18,18-difluoro-2,10- dihydroxy-2,10-disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 737 
               
               
                   
               
               
                 158 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-18,18-difluoro-2,10- dihydroxy-2,10-disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 737 
               
               
                   
               
               
                 159 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-18,18-difluoro-2,10- dihydroxy-2,10-disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 3) 
                 737 
               
               
                   
               
               
                 160 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-18,18-difluoro-2,10- dihydroxy-2,10-disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 4) 
                 737 
               
               
                   
               
               
                 161 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 690 
               
               
                   
               
               
                 162 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 690 
               
               
                   
               
               
                 163 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 3) 
                 690 
               
               
                   
               
               
                 164 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 4) 
                 690 
               
               
                   
               
               
                 165 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 728 
               
               
                   
               
               
                 166 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 728 
               
               
                   
               
               
                 167 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 3) 
                 728 
               
               
                   
               
               
                 168 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 708 
               
               
                   
               
               
                 169 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 708 
               
               
                   
               
               
                 170 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 3) 
                 708 
               
               
                   
               
               
                 171 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(2R,5S,7R,8R,10R, 12aR,14R,15S,15aR)-14-(4-amino-7H- pyrrolo[2,3-d]pyrimidin-7-yl)-15-fluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 690 
               
               
                   
               
               
                 172 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 690 
               
               
                   
               
               
                 173 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(2R,5R,7R,8S,10R, 12aR,14R,15S,15aR,16S)-14-(4-amino-7H- pyrrolo[2,3-d]pyrimidin-7-yl)-15,16-difluoro- 2,10-dihydroxy-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 1) 
                 708 
               
               
                   
               
               
                 174 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,9-dihydro- 6H-purin-6-one (Diastereomer 2) 
                 708 
               
               
                   
               
               
                 175 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (6-amino-9H-purin-9-yl)-15-fluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1) 
                 692 
               
               
                   
               
               
                 176 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (6-amino-9H-purin-9-yl)-15-fluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 692 
               
               
                   
               
               
                 177 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro- 7H-[1,2,3]triazolo[4,5-d] pyrimidin-7-one (Diastereomer 1) 
                 710 
               
               
                   
               
               
                 178 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin- 7-one (Diastereomer 2) 
                 710 
               
               
                   
               
               
                 179 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin- 7-one (Diastereomer 3) 
                 710 
               
               
                   
               
               
                 180 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 1-[(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,5-dihydro-4H- imidazo[4,5-c]pyridin-4-one 
                 693 
               
               
                   
               
               
                 181 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15-fluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 1) 
                 693 
               
               
                   
               
               
                 182 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15-fluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphosphacyclo- tetradecin-7-yl]-3,6-dihydro-7H-[1,2,3] triazolo[4,5-d]pyrimidin-7-one (Diastereomer 2) 
                 693 
               
               
                   
               
               
                 183 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15-fluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 3) 
                 693 
               
               
                   
               
               
                 184 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 1) 
                 702 
               
               
                   
               
               
                 185 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 2) 
                 702 
               
               
                   
               
               
                 186 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-3,6- dihydro-7H-[1,2,3]triazolo[4,5-d] pyrimidin-7-one (Diastereomer 3) 
                 702 
               
               
                   
               
               
                 187 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15R,15aS)-14- (6-amino-9H-purin-9-yl)-2,10-dihydroxy-2,10- disulfidohexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 4) 
                 702 
               
               
                   
               
               
                 188 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15aS)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2-l] [1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1) 
                 673 
               
               
                   
               
               
                 189 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15aS)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro- 7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 673 
               
               
                   
               
               
                 190 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15aS)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 3) 
                 673 
               
               
                   
               
               
                 191 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15-fluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 708 
               
               
                   
               
               
                 192 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15-fluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 708 
               
               
                   
               
               
                 193 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
                 706 
               
               
                   
               
               
                 194 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d] pyrimidin-7-one (Diastereomer 1) 
                 691 
               
               
                   
               
               
                 195 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 2) 
                 691 
               
               
                   
               
               
                 196 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 3) 
                 691 
               
               
                   
               
               
                 197 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 1) 
                 710 
               
               
                   
               
               
                 198 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 2) 
                 710 
               
               
                   
               
               
                 199 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 3) 
                 710 
               
               
                   
               
               
                 200 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d] pyrimidin-3-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 1) 
                 711 
               
               
                   
               
               
                 201 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H-[1,2,3] triazolo[4,5-d]pyrimidin-7-one (Diastereomer 2) 
                 711 
               
               
                   
               
               
                 202 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one 
                 711 
               
               
                   
               
               
                 203 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15R,15aS,18S)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-3,6-dihydro- 7H-[1,2,3]triazolo[4,5-d]pyrimidin-7- one (Diastereomer 1) 
                 720 
               
               
                   
               
               
                 204 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15R,15aS,18S)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 2) 
                 720 
               
               
                   
               
               
                 205 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15R,15aS,18S)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7(12H)-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 3) 
                 720 
               
               
                   
               
               
                 206 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16S)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5-d] pyrimidin-7-one 
                 709 
               
               
                   
               
               
                 207 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,112aR,14R,15aS,16S)- 14-(6-amino-9H-purin-9-yl)-12a-ethynyl-16- fluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 1) 
                 716 
               
               
                   
               
               
                 208 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,112aR,14R,15aS,16S)- 14-(6-amino-9H-purin-9-yl)-12a-ethynyl-16- fluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin- 7-one (Diastereomer 2) 
                 716 
               
               
                   
               
               
                 209 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,112aR,14R,15aS,16S)- 14-(6-amino-9H-purin-9-yl)-12a-ethynyl-16- fluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphosphacyclo- tetradecin-7-yl]-3,6-dihydro-7H-[1,2,3] triazolo[4,5-d]pyrimidin-7-one (Diastereomer 3) 
                 716 
               
               
                   
               
               
                 210 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,12aR,14R,15aS,16S)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- fluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 1) 
                 692 
               
               
                   
               
               
                 211 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,12aR,14R,15aS,16S)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- fluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 692 
               
               
                   
               
               
                 212 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 1) 
                 692 
               
               
                   
               
               
                 213 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 692 
               
               
                   
               
               
                 214 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 1) 
                 725 
               
               
                   
               
               
                 215 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 2) 
                 725 
               
               
                   
               
               
                 216 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 3) 
                 725 
               
               
                   
               
               
                 217 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(2R,5R,7R,8R,10R,12aR,14R,15S,15aR,16S)- 14-(6-amino-9H-purin-9-yl)-15,16-difluoro- 2,10-dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 4) 
                 725 
               
               
                   
               
               
                 218 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 1) 
                 726 
               
               
                   
               
               
                 219 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 726 
               
               
                   
               
               
                 220 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,12aR,14R,15aR,16S)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)- 15,15,16-trifluoro-2,10-dihydroxy-2,10- disulfidooctahydro-12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one 
                 727 
               
               
                   
               
               
                 221 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro- 7H-[1,2,3]triazolo[4,5-d] pyrimidin-7-one (Diastereomer 1) 
                 726 
               
               
                   
               
               
                 222 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro- 7H-[1,2,3]triazolo[4,5-d] pyrimidin-7-one (Diastereomer 2) 
                 726 
               
               
                   
               
               
                 223 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dihydroxy-2,10-disulfidooctahydro-12H-5,8- methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 3) 
                 726 
               
               
                   
               
               
                 224 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d] pyrimidin-3-yl)-15,16-difluoro-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7- yl]-3,6-dihydro-7H-[1,2,3] triazolo[4,5-d]pyrimidin- 7-one (Diastereomer 1) 
                 727 
               
               
                   
               
               
                 225 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin- 3-yl)-15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one (Diastereomer 2) 
                 727 
               
               
                   
               
               
                 226 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin- 7-one (Diastereomer 1) 
                 725 
               
               
                   
               
               
                 227 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-3,6-dihydro-7H- [1,2,3]triazolo[4,5-d] pyrimidin-7-one (Diastereomer 2) 
                 725 
               
               
                   
               
               
                 228 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 1-[(5S,7R,8R,12aR,14R,15S,15aR)- 14-(4-amino-7H-pyrrolo[2,3-d] pyrimidin-7-yl)-15-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,5-dihydro-4H-imidazo[4,5-c]pyridin-4-one 
                 674 
               
               
                   
               
               
                 229 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 6-amino-1- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,5-dihydro- 4H-imidazo[4,5-c]pyridin-4-one (Diastereomer 1) 
                 707 
               
               
                   
               
               
                 230 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 6-amino-1- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15,16- difluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphospha- cyclotetradecin-7-yl]-1,5-dihydro-4H- imidazo[4,5-c]pyridin-4-one (Diastereomer 2) 
                 707 
               
               
                   
               
               
                 231 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin- 3-yl)-15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 726 
               
               
                   
               
               
                 232 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d] pyrimidin-3-yl)-15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 726 
               
               
                   
               
               
                 233 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(7- amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
                 726 
               
               
                   
               
               
                 234 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15- fluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 706 
               
               
                   
               
               
                 235 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-14-(6- amino-9H-purin-9-yl)-15,16-difluoro-2,10- dioxido-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H- [1,2,3]triazolo[4,5-d]pyrimidin-7-one 
                 726 
               
               
                   
               
               
                 236 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 744 
               
               
                   
               
               
                 237 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 2) 
                 744 
               
               
                   
               
               
                 238 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
                 744 
               
               
                   
               
               
                 239 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7-yl]-1,9-dihydro-6H- purin-6-one (Diastereomer 4) 
                 744 
               
               
                   
               
               
                 240 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 735 
               
               
                   
               
               
                 241 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2-l] [1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 735 
               
               
                   
               
               
                 242 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,18R)-14-(6- amino-9H-purin-9-yl)-18-fluoro-2,10-dioxido- 2,10-disulfanylhexahydro-14H-15,12a- (epoxymethano)-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphospha- cyclotetradecin-7(12H)-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 3) 
                 735 
               
               
                   
               
               
                 243 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16R)-14-(7- amino-3H-imidazo[4,5-b]pyridin-3-yl)- 15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7- yl]-1,9-dihydro-6H-purin-6-one 
                 724 
               
               
                   
               
            
           
         
       
     
     Examples 244, 245, 246, and 247: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,1-dihydroxy-2,1-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1-3) and 2-amino-9-1(2R,5R,7R,8S,10R,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 4) 
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     Step 1. (2R,3R,4R,5R)-5-((((((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate 
     
       
         
         
             
             
         
       
     
     Pyrrole (0.087 mL, 1.2 mmol) was added to a solution of (2R,3S,4R,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate triethylamine salt (1:2) (0.34 g, 0.41 mmol) in acetonitrile (3.0 mL) under an argon atmosphere at 0° C. After 5 min, TFA (0.096 mL, 0.14 mmol) was added, and the reaction mixture was stirred at 0° C. for 30 min. Pyridine (0.13 mL, 1.7 mmol) was added drop wise at 0° C. The reaction mixture was then stirred for 10 min at 0° C. At that time, a mixture of (2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl (2-cyanoethyl) diisopropylphosphoramidite (0.48 g, 0.55 mmol) in acetonitrile (3.0 mL) was added drop wise over 5 min to the reaction mixture under an argon atmosphere at 0° C. The reaction mixture was stirred at 0° C. for 20 min and immediately used in the next step without further manipulation. 
     Step 2: (2R,3S,4R,5R)-5-((((((2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate 
     
       
         
         
             
             
         
       
     
     To the crude reaction mixture from Step 1 was added (E)-N,N-dimethyl-N′-(3-thioxo-3H-1,2,4-dithiazol-5-yl)formimidamide (0.10 g, 0.50 mmol) under an argon atmosphere at 0° C. The reaction mixture was stirred for 45 minutes at 0° C. At that time, 1-propanol (0.31 mL, 4.13 mmol) was added to the reaction mixture under an argon atmosphere at 0° C. The reaction mixture was then allowed to warm to ambient temperature and stirred for 10 min. TFA (0.32 mL, 4.1 mmol) was added to the reaction mixture, and the reaction mixture was stirred for 30 min at ambient temperature. Pyridine (0.37 mL, 4.6 mmol) was added at ambient temperature, and the reaction mixture was stirred for 10 min. The reaction mixture was concentrated under reduced pressure to approximately one-half volume. The mixture was then diluted with isopropyl acetate (20 mL) and stirred for 30 min at ambient temperature. The resulting suspension was filtered. 
     The collected solids were dried overnight under high vacuum to afford (2R,3 S,4R,5R)-5-((((((2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate. LCMS (ES, m/z): 922 [M−H] − . 
     Step 3: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     (2R,3 S,4R,5R)-5-((((((2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)-methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate (0.30 g, 0.33 mmol) was azeotroped with dry pyridine (2×10 mL) and then dried under high vacuum for 1 h. In a separate flask, diphenyl phosphorochloridate (0.34 mL, 1.6 mmol) was added to a mixture of acetonitrile (15 mL) and pyridine (1.0 mL). The resulting solution was then cooled to −20° C. To this mixture was added drop wise over a period of 5 min a mixture of (2R,3 S,4R,5R)-5-((((((2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphorothioyl)oxy)-methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl hydrogen phosphonate (0.30 g, 0.33 mmol) in pyridine (4.0 mL) at −20° C. The reaction mixture was then stirred at −20° C. for 15 min post-addition. 3H-benzo[c][1,2]dithiol-3-one (0.066 g, 0.39 mmol) and water (0.12 mL, 6.5 mmol) were then added to the reaction mixture at −20° C. The reaction mixture was allowed to gradually warm to ambient temperature. The reaction mixture was stirred for 30 min at ambient temperature. The reaction mixture was then concentrated under reduced pressure to approximately one quarter volume. The reaction mixture was cooled to 0° C., and methanamine (33% in ethanol) (2.63 mL, 24 mmol) was added drop wise. After the addition was complete, the reaction mixture was allowed to warm to ambient temperature. The reaction mixture was stirred at ambient temperature for 18 h. The reaction mixture was concentrated under reduced pressure to afford the crude product residue. The crude product residue was azeotroped (3×30 mL ethanol) to afford the crude product. This material was dissolved in water (5 mL) and acetonitrile (1 mL). The resulting mixture was purified by mass-directed reverse phase HPLC (Waters Sunfire 19×250 mm, UV 215/254 nm, fraction trigger by SIM negative MS monitoring mass 709; mobile phase=100 mM triethylammonium acetate in water/acetonitrile gradient, 2-30% acetonitrile over 40 min) to afford the 4 diastereomers of 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15 aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one. 
     Example 244: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1): T R =17.7 min. LCMS (ES, m/z): 709 [M−H] − . 
     Example 245: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2): T R =21.9 min. LCMS (ES, m/z): 709 [M−H] − . 1H NMR (500 MHz, DMSO-d 6 ) δ 8.32 (s, 1H), 8.21-8.09 (m, 2H), 7.46-7.29 (m, 2H), 6.59-6.43 (m, 2H), 6.40-6.29 (m, 1H), 5.88 (d, J=8.8 Hz, 1H), 5.49-5.19 (m, 4H), 4.45-4.32 (m, 2H), 4.10-3.93 (m, 2H), 3.94-3.82 (m, 1H), 3.80-3.68 (m, 1H). 
     Example 246: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3): T R =23.8 min. LCMS (ES, m/z): 709 [M−H] − . 1H NMR (500 MHz, DMSO-d 6 ) δ 8.18-8.08 (m, 3H), 7.41-7.33 (m, 2H), 6.59-6.47 (m, 2H), 6.37-6.27 (m, 1H), 5.84 (d, J=8.7 Hz, 1H), 5.52-5.26 (m, 2H), 5.21-5.11 (m, 1H), 4.46-4.35 (m, 2H), 4.19-4.02 (m, 2H), 3.83-3.65 (m, 2H). 
     Example 247: 2-amino-9-[(2R,5R,7R,8S,10R,12aR,14R,15S,15 aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 4): T R =26.4 min. LCMS (ES, m/z): 709 [M−H] − .  1 H NMR (500 MHz, DMSO-d 6 ) δ 8.19-8.07 (m, 3H), 7.41-7.32 (m, 2H), 6.70-6.50 (m, 2H), 6.40-6.29 (m, 1H), 5.85 (d, J=8.7 Hz, 1H), 5.33-5.25 (m, 2H), 5.23-5.12 (m, 1H), 4.48-4.35 (m, 1H), 4.33-4.24 (m, 1H), 4.09-3.93 (m, 2H), 3.92-3.81 (m, 1H), 3.83-3.70 (m, 1H). 
     Examples 248 through 256, as shown in Table 7 below, were prepared according to procedures analogous to those outlined in Examples 244 through 247 above using the appropriate monomers, described as Preparations or as obtained from commercial sources, in the coupling step. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 7 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 248 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-16- fluoro-2,10-dioxido-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 691 
               
               
                   
               
               
                 249 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)- 14-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)- 16-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 691 
               
               
                   
               
               
                 250 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)- 14-(4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)- 16-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
                 691 
               
               
                   
               
               
                 251 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)- 14-(4-aminoimidazo[2,1-f)[1,2,4]triazin-7-yl)- 16-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 4) 
                 691 
               
               
                   
               
               
                 252 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin- 7-yl)-16-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 708 
               
               
                   
               
               
                 253 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin- 7-yl)-16-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 708 
               
               
                   
               
               
                 254 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin- 7-yl)-16-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
                 708 
               
               
                   
               
               
                 255 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-amino-5-fliioro-7H-pyrrolo[2,3-d]pyrimidin- 7-yl)-16-fluoro-10-hydroxy-2,10-dioxido-2- sulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 692 
               
               
                   
               
               
                 256 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,4R,15aS,16R)-14- (4-amino-5-fliioro-7H-pyrrolo[2,3-d]pyrimidin- 7-yl)-16-fluoro-10-hydroxy-2,10-dioxido-2- sulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 692 
               
               
                   
               
            
           
         
       
     
     Examples 257 through 259 in Table 8 were made according to procedures analogous to those described above for Examples 244 through 247 using the appropriate monomeric nucleosides, described as Preparations or as obtained from commercial sources, with the following additional representative treatment as a final step: A sample (0.12 mmol) was dissolved in water (6 mL), and the resulting mixture was applied to ion exchange resin in a column (DOWEX 50WX2 hydrogen form, 100-200 mesh, 1.5 g, pre-washed with 10 mL water, and then packed in column before compound loading occurred). After loading mixture had completely absorbed to column, the column was then washed with additional water (10 mL). The eluent was lyophilized to afford product. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 8 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 257 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 691 
               
               
                   
               
               
                 258 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 691 
               
               
                   
               
               
                 259 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-16- fluoro-2,10-dihydroxy-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3) 
                 691 
               
               
                   
               
            
           
         
       
     
     Alternatively, Examples 117-142, 144-152, 172, 174, and 244-247, above were made using procedures similar to those described for Examples 81 through 83 above. 
     Example 260: 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     Step 1. ((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-3-((triethylsilyl)oxy)tetrahydrofuran-2-yl)methyl (2-cyanoethyl) diisopropylphosphoramidite 
     
       
         
         
             
             
         
       
     
     To a solution of N-(9-((2R,3R,4R,5R)-3-fluoro-4-hydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl)-9H-purin-6-yl)benzamide (780 mg, 2.089 mmol) in DMF (8 mL) and DIPEA (1.116 mL, 6.39 mmol) at 0° C. was added 200 mg active molecular sieve 4 Å and 2-cyanoethyl N,N-diisopropylchlorophosphoramidite (572 mg, 2.343 mmol) in 1 ml dry CH 3 CN. The resulting mixture was stirred at 0° C. for 5 h; chlorotriethylsilane (401 mg, 2.66 mmol) was added dropwise. The resulting mixture was stirred at rt overnight. The reaction carried directly to next step. LCMS (ES, m/z): 686 [M−H] −   
     Step 2: O-(((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-3-((triethylsilyl)oxy) tetrahydrofuran-2-yl)methyl)O-((2R,3S,4R,5R)-5-(((tert-butyldimethylsilyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)O-(2-cyanoethyl) phosphorothioate 
     
       
         
         
             
             
         
       
     
     To a solution of the product of step 1 was added N-(9-((2R,3 S,4S,5R)-5-(((tert-butyldimethylsilyl)oxy)methyl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (500 mg, 1.065 mmol) and 1H-tetrazole (895 mg, 12.78 mmol). The mixture was stirred at RT for 2 h, and DDTT (568 g, 2.77 mmol) was added. The mixture was stirred for 1 h, then partitioned between ethyl acetate and H 2 O, dried over Na 2 SO 4 , filtered and concentrated in vacuo. The residue was purified by column chromatography on silica gel, eluting with 0-6% MeOH/DCM to give O-(((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-3-((triethyl silyl)oxy)tetrahydrofuran-2-yl)methyl)O-((2R,3S,4R,5R)-5-(((tert-butyldimethylsilyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)O-(2-cyanoethyl) phosphorothioate. LCMS (ES, m/z): 1088 [M+H] +   
     Step 3: O-(((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)methyl)O-((2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl)O-hydrogen phosphorothioate 
     
       
         
         
             
             
         
       
     
     To a solution of the mixture (520 mg) from step 3 in THF (5 mL) was added TBAF (1.0 M in THF) (1.140 mL, 1.140 mmol). The resulting mixture was stirred at RT for 2 h and concentrated in vacuo. The residue was purified by column chromatography on silica gel, eluting with 0-8% MeOH/DCM to give O-(((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)methyl)O-((2R,3 S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1H-purin-9(6H)-yl)tetrahydrofuran-3-yl)O-hydrogen phosphorothioate. LCMS (ES, m/z): 807 [M+H] +   
     Step 4. N-{9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-15,16-difluoro-2,10-dihydroxy-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purin-6-yl}benzamide 
     
       
         
         
             
             
         
       
     
     O-(((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)methyl)O-((2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1H-purin-9(6H)-yl)tetrahydrofuran-3-yl)O-hydrogen phosphorothioate (250 mg, 0.310 mmol) and diisopropylammonium tetrazolide (80 mg, 0.465 mmol) were azeotrope with dry CH 3 CN (3×10 ml) and dried under high vacuum for 30 min. 
     The above mixture was dissolved in DMF (1 mL) and acetonitrile (7 mL) and added 200 mg active molecular sieve 4 Å and a solution of 2-cyanoethyl N,N,N′,N′-tetraisopropylphosphorodiamidite (128 mg, 0.403 mmol) in 1 ml dry CH 3 CN. The resulting mixture was stirred at rt for 30 min, followed by addition of 1H-tetrazole (109 mg, 1.550 mmol). The reaction stayed at rt for 1 h and added DDTT (95 mg, 0.465 mmol). The stirring continued for 1 h and concentrated in vacuo. The residue was purified by column chromatography on silica gel, eluting with 0-10% MeOH/DCM with 1% ET3N to give the desired product. LCMS (ES, m/z): 883 [M−H] − . 
     Step 5: 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     N-{9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-15,16-difluoro-2,10-dihydroxy-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purin-6-yl}benzamide (120 mg, 0.136 mmol) and ammonia (7.0M in MeOH) (2 ml, 14.00 mmol) were sealed in a microwave tube. The reaction mixture was heated to 50° C. and stirred for 4 h. The reaction mixture was concentrated, and purified using mass-directed reverse phase HPLC (X-Bridge BEH 150 Prep C18) using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate to give desired product. Lyopholization of the product fractions furnished 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]-pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one. LCMS (ES, m/z): 709 [M−H] − .  1 H NMR (H 2 O-d2, 500 MHz): δ H  8.23 (1H, s), 8.17 (1H, s), 7.93 (1H, s), 6.43 (1H, d, J=15.0 Hz), 6.00 (1H, d, J=8.7 Hz), 5.75 (1H, m), 5.58 (2H, m), 5.15 (1H, m), 4.65 (2H, m), 4.54 (1H, m), 4.15-4.30 (3H, m).  31 P NMR: (H 2 O-d 2 , 202 MHz): δ 52.1, 52.2. 
     Examples 261, 262, 263: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(4-amino-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-12a-ethynyl-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1-3) 
     
       
         
         
             
             
         
       
     
     Step 1: ((2R,3R,4S,5R)-4-(((2-cyanoethoxy)(diisopropylamino)phosphanyl)oxy)-3-fluoro-5-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-2-yl)methyl (2-cyanoethyl) diisopropylphosphoramidite 
     
       
         
         
             
             
         
       
     
     To a solution of N-(9-((2R,3R,4S,5R)-4-fluoro-3-hydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl)-6-oxo-6,9-dihydro-1H-purin-2-yl)isobutyramide (190 mg, 0.535 mmol) and 3-((bis(diisopropylamino)phosphino)oxy)propanenitrile (95%) (373 mg, 1.176 mmol) in DMF (5 ml) was added diisopropylammonium tetrazolide (137 mg, 0.802 mmol). The mixture was stirred at RT for 2 h, then added 1H-tetrazole (15.77 mg, 0.225 mmol) and continued for 2 h. 300 mg active molecular sieve 4 Å was added and continued stirring at RT for 2 h. The reaction carried directly to next step. LCMS (ES, m/z): 754 [M−H] −   
     Step 2: N-{7-[(5R,7R,8S,12aR,14R,15aS,16R)-2,10-bis(2-cyanoethoxy)-12a-ethynyl-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide 
     
       
         
         
             
             
         
       
     
     To a solution of N-(7-((2R,4S,5R)-5-ethynyl-4-hydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl)-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-4-yl)benzamide (180 mg, 0.454 mmol) and Et 3 N (0.114 mL, 0.817 mmol) in DMF (4 mL) at −78° C. was added a solution of TMS-Cl (0.070 mL, 0.545 mmol) in CH 2 Cl 2  (1 mL) dropwise. The mixture was stirred at −78° C. for 20 min and warmed to 0° C. within 1 h, then added 200 mg active molecular sieve 4 Å and continued stirring at RT for 2 h. The mixture was cooled to 0° C. and transferred to a stirred solution of the product of Step 1 (394 mg, 0.454 mmol) (precooled to −0° C.), followed by addition of 1H-tetrazole (191 mg, 2.72 mmol). The mixture was gradually warmed to RT and stirred at RT for 2 h. The filtration removed the solids. After washed with 3 ml DMF, the combined filtrate was added additional 1H-tetrazole (191 mg, 2.72 mmol) and stirred at RT overnight. 
     After completion of reaction, the reaction mixture was diluted with ethyl acetate and washed successively with H 2 O and brine. The organic layer was dried over anhydrous Na 2 SO 4  and purified by a silica gel chromatography, eluting with 0-8% MeOH/DCM to give two desired fractions with the same molecular weight. LCMS (ES, m/z): 1014 [M+H] +   
     Step 3: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(4-amino-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-12a-ethynyl-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     N-{7-[(5R,7R,8S,12aR,14R,15aS,16R)-2,10-bis(2-cyanoethoxy)-12a-ethynyl-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide (faster fraction from step 2) (30 mg, 0.030 mmol) and 7.0M ammonia in MeOH (2 ml, 14.00 mmol) were sealed in a microwave tube. The mixture was heated to 50° C. and stirred for 8 h. The reaction mixture was concentrated, and the product was purified using mass-directed reverse phase HPLC (X-Bridge BEH 150 Prep C18) using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate. Lyopholization of the product fractions furnished 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(4-amino-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-12a-ethynyl-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one as the bis-triethylamine salt. 
     Example 261 (Diastereomer 1): LCMS (ES, m/z): 732 [M−H] − .  1 H NMR (H 2 O-d 2 , 500 MHz): δ H  8.32 (1H, s), 8.08 (1H, s), 7.05 (1H, s), 6.70 (1H, t, J=6.1 Hz), 6.08 (1H, d, J=8.7 Hz), 5.71 (1H, d, J=53.2 Hz), 5.47-5.40 (1H, m), 5.14-5.10 (1H, m), 4.65 (2H, m), 4.28 (1H, t, J=8.7 Hz), 4.14-4.02 (3H, m), 2.85 (2H, d, J=6.4 Hz).  31 P NMR: (H 2 O-d 2 , 202 MHz): δ 53.7, 54.0. 
     Step 4: 2-amino-9-[(5R,7R,8S,12aR,14R,15aS,16R)-14-(4-amino-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-12a-ethynyl-16-fluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     N-{7-[(5R,7R,8S,12aR,14R,15aS,16R)-2,10-bis(2-cyanoethoxy)-12a-ethynyl-16-fluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-4-yl}benzamide (slow fraction from Step 2, 65 mg, 0.064 mmol) and 7.0 M ammonia in MeOH (2 ml, 14.00 mmol) were sealed in a microwave tube and heated to 50° C. and stirred for 8 h. The reaction mixture was concentrated and purified using mass-directed reverse phase HPLC (X-Bridge BEH 150 Prep C18) using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate to give two additional diastereomers after lyopholization of the product fractions. 
     Example 262 (Diastereomer 2): LCMS (ES, m/z): 732 [M−H] − .  1 H NMR (H 2 O-d 2 , 500 MHz): δ H  8.09 (2H, d, J=3.0 Hz), 7.19 (1H, s), 6.74 (1H, s), 6.08 (1H, d, J=8.3 Hz), 5.63 (1H, s), 5.53 (1H, s), 5.35-5.33 (1H, m), 4.65 (2H, m), 4.34 (1H, d, J=8.8 Hz), 4.28 (1H, t, J=10.3 Hz), 4.11 (1H, d, J=12.1 Hz), 3.89 (1H, dd, J=10.6, 4.0 Hz), 2.85 (2H, d, J=6.4 Hz).  31 P NMR: (H 2 O-d 2 , 202 MHz): δ 54.7, 59.8. 
     Example 263 (Diastereomer 3): LCMS (ES, m/z): 732 [M−H] − .  1 H NMR (H 2 O-d 2 , 500 MHz): δ H  8.08 (1H, s), 7.94 (1H, s), 7.04 (1H, s), 6.68 (1H, s), 6.04 (1H, d, J=8.6 Hz), 5.64 (1H, s), 5.54 (1H, d, J=3.3 Hz), 5.24 (1H, d, J=7.7 Hz), 4.65 (2H, m), 4.40 (1H, d, J=8.2 Hz), 4.18 (1H, dd, J=11.0, 5.5 Hz), 4.09-4.00 (2H, m), 2.93-2.89 (1H, m), 2.82 (1H, d, J=7.1 Hz).  31 P NMR: (H 2 O-d 2 , 202 MHz): δ 53.1, 54.9. 
     Examples 264 and 265: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-2,10,18-trihydroxy-2-oxido-10-sulfidohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-7(12H)-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) and 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-2,10,18-trihydroxy-2-oxido-10-sulfidohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-7(12H)-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
     
       
         
         
             
             
         
       
     
     Step 1: (2R,3R,4S,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of (2R,3R,4S,5R)-5-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate (750 mg, 0.865 mmol) in CH 2 Cl 2  (9 mL) was added water (156 mg, 8.65 mmol) and 2,2-dichloroacetic acid in CH 2 Cl 2  (0.6M, 11 mL, 6.6 mmol). The mixture was stirred at rt for 15 min, and then, Et 3 SiH (4.00 mL) was added. After 1 h, pyridine (1232 mg, 15.57 mmol) was added, and it was concentrated to give a crude sample that was used for next reaction step without purification. LCMS (ES, m/z): 548.1 [M+H] + . 
     Step 2. (2R,3R,4S,5R)-5-((((((R, 3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     The crude sample from Step 1 was co-evaporated with ACN (3×2 mL), re-dissolved in ACN (3 mL), and dried by adding activated 4 Å molecular sieve (150 mg). (1R,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl (2-cyanoethyl) diisopropylphosphoramidite (0.843 g, 0.952 mmol) was also co-evaporated with ACN (3×1 mL), re-dissolved in ACN (3 mL), and dried by adding activated 4 Å molecular sieve (150 mg). After 30 min, it was added to the previously prepared mixture containing pyridin-1-ium (2R,3R,4S,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate. The reaction mixture was used in the next reaction step without purification. LCMS (ES, m/z): 1332.1 [M+H] + . 
     Step 3. (2R,3R,4S,5R)-5-((((((R, 3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-2,5-dioxabicyclo[2.2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a reaction mixture from Step 2 at rt was added 2-hydroperoxy-2-methylpropane (0.234 g, 2.60 mmol), and it was stirred for 40 min. It was concentrated to give a crude product, which was used for the next step without purification. LCMS (ES, m/z): 1347.1 [M+H] + . 
     Step 4: (2R,3R,4S,5R)-5-((((((1S,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-(hydroxymethyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-((tert-butyldimethylsilyl)oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To the crude from Step 3 in CH 2 Cl 2  (9 mL) was added water (156 mg, 8.65 mmol) and 2,2-dichloroacetic acid in CH 2 Cl 2  (0.6N, 10 mL, 6 mmol). The resulting mixture was stirred at rt for 15 min. Then, triethylsilane (4 mL, 0.21 mmol) was added, and the stirring was continued for 40 min. Pyridine (1232 mg, 15.57 mmol) was added. The mixture was concentrated, and the residue was purified by reverse phase (C18) chromatography eluted with 0 to 95% ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 1046.3 [M+H] + . 
     Step 5. (5R,7R,8R,12aR,14R,15R,15aS,18S)-18-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-10(12H)-olate 2-oxide 
     
       
         
         
             
             
         
       
     
     To pyridine (20 mL) at −40° C. under Ar was added diphenyl phosphorochloridate (1.28 g, 4.78 mmol) over 5 min. To the solution at −40° C. was added a solution of (2R,3R,4S,5R)-5-((((((1 S,3R,4R,7S)-3-(6-benzamido-9H-purin-9-yl)-1-(hydroxymethyl)-2,5-dioxabicyclo[2.2.1]heptan-7-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-((tert-butyldimethylsilyl) oxy)-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrothiophen-3-yl phosphonate (250 mg, 0.239 mmol, co-evaporated with pyridine, 3×10 mL) in CH 2 Cl 2  (20 mL) dropwise. The resulting mixture was stirred at −40° C. for 30 min. The reaction mixture was used for the next reaction step immediately without purification. LCMS (ES, m/z): 1028.4 [M+H] + . 
     Step 6: (5R,7R,8R,12aR,14R,15R,15aS,18S)-18-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-10(12H)-olate 2-oxide 10-sulfide 
     
       
         
         
             
             
         
       
     
     To the reaction mixture at rt from Step 5 was added 3H-benzo[c][1,2]dithiol-3-one (121 mg, 0.717 mmol). After stirring at 25° C. for 40 min, water (431 mg, 23.9 mmol) was added. The reaction mixture was concentrated under reduced pressure, and the residue was purified by reverse phase (C, 18) chromatography eluted with 0 to 95% ACN in aq NH 4 HCO 3  (5 mM) to give the product. LCMS (ES, m/z): 1060.3 [M+H] + .  31 P-NMR: (121 MHz, D 2 O) δ 54.91, 54.61 (m, 1P), δ −6.08, −6.48 (m, 1P). 
     Step 7: (5R,7R,8R,12aR,14R,15R,15aS,18S)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-18-{[tert-butyl(dimethyl)silyl]oxy}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecine-2,10(12H)-diolate 2-oxide 10-sulfide 
     
       
         
         
             
             
         
       
     
     (5R,7R,8R,12aR,14R,15R,15aS,18S)-18-{[tert-butyl(dimethyl)silyl]oxy}-2-(2-cyanoethoxy)-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}hexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-10(12H)-olate 2-oxide 10-sulfide (190 mg, 0.178 mmol) was dissolved in a solution of methylamine in EtOH (30%, 1 mL), and the resulting solution was stirred at rt for 2 h. Then, it was concentrated to give a crude sample containing the product. LCMS (ES, m/z): 833.2 [M+H] + . 
     Step 8: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-2,10,18-trihydroxy-2-oxido-10-sulfidohexahydro-14H-15,2a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-7(12H)-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     The crude from Step 7 was suspended in pyridine (5 mL) under Ar. To the mixture was added Et 3 N (1864 mg, 18.42 mmol) and triethylamine trihydrofluoride (742 mg, 4.60 mmol) dropwise. The mixture was heated to 50° C. for 16 h. Then, it was concentrated, and the residue was purified by preparative-HPLC (XBridge Shield RP18 OBD Column, 19×150 mm) eluted with 0 to 14% ACN in aq NH 4 HCO 3  (10 mM) over 16 min to give two products after concentration. 
     Example 264: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-2,10,18-trihydroxy-2-oxido-10-sulfidohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-7(12H)-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1): T R : 11.00 min. LCMS (ES, m/z): 719.0 [M+H] + .  1 H-NMR: (300 MHz, D 2 O): δ 8.13 (s, 1H), 7.94 (s, 1H), 7.64 (s, 1H), 6.11-5.97 (m, 2H), 5.92-5.85 (m, 1H), 5.25-5.05 (m, 1H), 4.87 (s, 1H), 4.75 (s, 2H), 4.30-4.21 (m, 1H), 4.12-3.78 (m, 4H), 3.50-3.45 (m, 1H).  31 P-NMR: (121 MHz, D 2 O) δ 52.06 (s, 1P), δ −0.86 (s, 1P) 
     Example 265: 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aS,18S)-14-(6-amino-9H-purin-9-yl)-2,10,18-trihydroxy-2-oxido-10-sulfidohexahydro-14H-15,12a-(epoxymethano)-5,8-methanofuro[3,2-l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin-7(12H)-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2): T R : 12.32 min. LCMS (ES, m/z): 719.0 [M+H] + .  1 H-NMR: (300 MHz, D 2 O): δ 8.13-8.03 (m, 2H), 7.64 (s, 1H), 6.11-5.97 (m, 2H), 5.92-5.90 (m, 1H), 5.20-5.15 (m, 1H), 4.87-4.75 (m, 3H), 4.33-4.20 (m, 1H), 4.12-4.00 (m, 2H), 3.90-3.78 (m, 2H), 3.45-3.40 (m, 1H). 31P-NMR: (121 MHz, D 2 O) δ 54.88 (s, 1P), δ-0.97 (s, 1P). 
     Examples 266 through 272, as shown in Table 9 below, were prepared according to procedures analogous to those outlined for Examples 264 and 265 above using the appropriate monomeric nucleosides, described as Preparations or as obtained from commercial sources. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 9 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] −   
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 266 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15S,15aR,16S)- 14-(6-amino-9H-purin-9-yl)-15-fluoro-2,10,16- trihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8- methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one 
                 707 
               
               
                   
               
               
                 267 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-2,16- dihydroxy-2,10-dioxido-10-sulfanyloctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotctradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1) 
                 690 
               
               
                   
               
               
                 268 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminopyrazolo[1,5-a][1,3,5]triazin-8-yl)-2,16- dihydroxy-2,10-dioxido-10-sulfanyloctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 690 
               
               
                   
               
               
                 269 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15S,15aR,16S)- 14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin- 3-yl)-15-fluoro-2,16-dihydroxy-2,10-dioxido-10- sulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1) 
                 709 
               
               
                   
               
               
                 270 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15S,15aR,16S)- 14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin- 3-yl)-15-fluoro-2,16-dihydroxy-2,10-dioxido-10- sulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 709 
               
               
                   
               
               
                 271 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,16- dihydroxy-2,10-dioxido-10-sulfanyloctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1) 
                 690 
               
               
                   
               
               
                 272 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8R,12aR,14R,15aS,16S)-14- (4-aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2,16- dihydroxy-2,10-dioxido-10-sulfanyloctahydro- 12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2) 
                 690 
               
               
                   
               
            
           
         
       
     
     Examples 273 and 274: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H1-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) and 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
     
       
         
         
             
             
         
       
     
     Step 1. (2R,3,4R,5R)-5-((((((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-, 6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a mixture containing the crude (2R,3S,4R,5R)-5-((((((2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-2-((bis(4-methoxyphenyl)(phenyl)methoxy)methyl)-4-fluorotetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphanyl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (product of Step 1, Examples 244-247, crude, assumed 0.75 mmol) was added tert-butyl hydroperoxide in decane (5.5M, 0.48 mL, 2.6 mmol) dropwise, and the mixture was stirred at rt for 1 h. Then, it was cooled to 0° C., and a solution of Na 2 S 2 O 3  (553 mg) in water (2 mL) was added slowly. The mixture was stirred at rt for 5 min and then, concentrated to give the product. LCMS (ES, m/z): 1208.5 [M−H] − . 
     Step 2: (2R,3S,4R,5R)-5-((((((2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate 
     
       
         
         
             
             
         
       
     
     To a solution of the crude from Step 1 in CH 2 Cl 2  (10 mL) was added water (130 mg, 7.5 mmol) and 2,2-dichloroacetic acid (0.77 g, 6 mmol) in CH 2 Cl 2  (10 mL). After 20 min, triethylsilane (20 mL) was added, and stirring was continued for 2 h. Pyridine (1 mL) was added, and the reaction mixture was concentrated. The residue was purified by reverse phase (C18) chromatography eluted with 0 to 95% ACN in aq NH 4 HCO 3  (0.04%) to give the product. LCMS (ES, m/z): 908.2 [M+H] + .  1 H-NMR: (400 MHz, CD 3 OD) δ 8.76 (d, J=7.7 Hz, 2H), 8.65 (s, 1H), 8.56 (s, 1H), 8.21-8.08 (m, 6H), 7.69 (t, J=7.4 Hz, 2H), 7.64-7.50 (m, 5H), 6.67 (ddd, J=32.7, 14.9, 4.4 Hz, 2H), 6.21-6.10 (m, 2H), 5.99-5.91 (m, 1H), 5.64-5.57 (m, 1H), 5.56-5.45 (m, 3H), 5.38 (s, 3H), 4.71-4.54 (m, 6H), 4.47-4.23 (m, 5H), 3.92 (d, J=3.8 Hz, 1H), 3.89-3.80 (m, 2H), 2.94 (dt, J=31.1, 5.9 Hz, 4H), 2.83-2.74 (m, 2H), 1.36-1.19 (m, 13H), 1.12 (s, 2H).  31 P-NMR: (162 MHz, CD 3 OD) δ 2.55, −1.33, −3.09, −3.11, −155.89. 
     Step 3. (5R,7R,8S,12aR,14R,15S,15aR,16R)-2-(2-cyanoethoxy)-15,16-difluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2-oxide 
     
       
         
         
             
             
         
       
     
     To pyridine (50 mL) under Ar was added diphenyl chlorophosphate (2.66 g, 9.92 mmol). It was cooled at −40° C., and then, a solution of (2R,3 S,4R,5R)-5-((((((2R,3R,4S,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl)oxy)(2-cyanoethoxy)phosphoryl)oxy)methyl)-4-fluoro-2-(2-isobutyramido-6-oxo-1,6-dihydro-9H-purin-9-yl)tetrahydrofuran-3-yl phosphonate (450 mg, 496 mmol, co-evaporated with pyridine 3×5 mL) in CH 2 Cl 2  (50 mL) was added dropwise over 20 min. The resulting mixture was stirred at −40° C. for 20 min. The reaction mixture was immediately used in the next step without purification. LCMS (ES, m/z): 891.1 [M+H] + . 
     Step 4: (5R,7R,8S,12aR,14R,15S,15aR,16R)-2-(2-cyanoethoxy)-15,16-difluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2-oxide 10-sulfide 
     
       
         
         
             
             
         
       
     
     To the reaction mixture of Step 3 at −40° C. was added 3H-benzo[c][1,2]dithiol-3-one (32.76 mg, 0.195 mmol) and water (125 mg, 0.744 mmol). After stirring at rt for 40 min, the reaction mixture was concentrated under reduced pressure. The residue was purified by reverse phase (C18) chromatography eluted with 0 to 95% ACN in aq NH 4 HCO 3  (0.04%) to give the product. LCMS (ES, m/z): 922.1 [M+H] + .  1 H-NMR: (400 MHz, CD 3 OD) δ 8.81-8.73 (m, 2H), 8.63-8.48 (m, 2H), 8.24 (s, 1H), 8.21-8.10 (m, 5H), 7.73-7.56 (m, 7H), 6.83-6.72 (m, 2H), 6.28 (d, J=8.6 Hz, 1H), 6.14 (d, J=8.5 Hz, 1H), 5.83-5.56 (m, 4H), 5.49 (d, J=11.1 Hz, 1H), 4.76-4.46 (m, 11H), 4.37 (s, 1H), 4.29 (d, J=6.8 Hz, 1H), 4.18 (d, J=10.2 Hz, 1H), 3.04 (dd, J=6.5, 5.1 Hz, 4H), 2.83-2.68 (m, 1H), 2.06 (s, 2H), 1.23 (dd, J=22.5, 6.9 Hz, 9H), 1.14-1.05 (m, 3H).  31 P-NMR: (162 MHz, CD 3 OD) δ62.41, 56.84, 56.29, −3.14, −3.35, −4.77, −5.06, −60.84. 
     Step 5: 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomers 1 and 2) 
     
       
         
         
             
             
         
       
     
     The (5R,7R,8S,12aR,14R,15S,15aR,16R)-2-(2-cyanoethoxy)-15,16-difluoro-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-14-{6-[(phenylcarbonyl)amino]-9H-purin-9-yl}octahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-10-olate 2-oxide 10-sulfide (380 mg, 0.377 mmol) was dissolved in a solution of MeNH 2  in EtOH (30%, 30 mL), and the resulting solution was stirred at rt for 2 h. Then, it was concentrated, and the residue was purified by Prep-HPLC (XBridge Shield RP18 OBD Column, 19×150 mm) eluted with 4 to 10% ACN in aq NH 4 HCO 3  (10 mM) over 20 min. 
     Example 273: 2-amino-9-[(5R,7R,8 S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1): T R =10.10 min. LCMS (ES, m/z): 693.0 [M−H] − .  1 H-NMR: (400 MHz, CDCl 3 ) δ 10.84 (d, J=2.4 Hz, 1H), 10.72 (s, 1H), 10.59 (d, J=3.9 Hz, 1H), 9.01 (dd, J=19.4, 3.0 Hz, 1H), 8.56 (d, J=8.5 Hz, 1H), 8.14-7.96 (m, 2H), 7.93-7.82 (m, 1H), 7.73 (dd, J=12.0, 6.5 Hz, 2H), 7.31-7.19 (m, 2H), 7.15 (d, J=2.8 Hz, 1H), 6.94-6.74 (m, 3H), 6.71-6.53 (m, 2H).  31 P-NMR: (162 MHz, D 2 O): δ 62.301 (s, 1P), 0.976 (s, 1P). 
     Example 274: 2-amino-9-[(5R,7R,8 S,12aR,14R,15S,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2): T R : 14.27 min. LCMS (ES, m/z): 692.9 [M−H] − .  1 H-NMR: (400 MHz, DMSO-d6) δ 8.31 (d, J=11.0 Hz, 2H), 8.18 (s, 1H), 6.40 (dd, J=22.6, 2.6 Hz, 1H), 5.88 (d, J=8.8 Hz, 1H), 5.44 (d, J=33.7 Hz, 2H), 5.35-5.23 (m, 1H), 5.24-5.05 (m, 2H), 4.48-4.34 (m, 1H), 4.31 (dd, J=10.6, 4.5 Hz, 1H), 4.16-3.87 (m, 3H).  31 P-NMR: (162 MHz, DMSO-d6): δ 55.096 (s, 1P), −2.731 (s, 1P). 
     Examples 275 through 288, as shown in Table 10 below, were prepared according to procedures analogous to those outlined in Examples 274 and 275 above using the appropriate monomeric nucleosides, described as Preparations or as obtained from commercial sources. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 10 
               
               
                   
               
               
                   
                   
                   
                 Mass 
               
               
                 Ex. 
                 Structure 
                 Name 
                 [M − H] 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 275 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4- amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-2,10- dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8- methanofuro[3,2-1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 1) 
                 656 
               
               
                   
               
               
                 276 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4- amino-7H-pyirolo[2,3-d]pyrimidin-7-yl)-2,10- dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8- methanofuro[3,2-1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]-1,9- dihydro-6H-purin-6-one (Diastereomer 2) 
                 656 
               
               
                   
               
               
                 277 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS,18S)- 14-(6-amino-9H-purin-9-yl)-18-fluoro-2,10- dihydroxy-2-oxido-10-sulfidohexahydro-14H- 15,12a-(epoxymethano)-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7(12H)-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 703 
               
               
                   
               
               
                 278 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aS,18S)- 14-(6-amino-9H-purin-9-yl)-18-fluoro-2,10- dihydroxy-2-oxido-10-sulfidohexahydro-14H- 15,12a-(epoxymethano)-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7(12H)-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 703 
               
               
                   
               
               
                 279 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)- 14-(7-amino-3H-[1,2,3]triazoIo[4,5-d]pyrimidin- 3-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10- sulfidooctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 694 
               
               
                   
               
               
                 280 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8S,12aR,14R,15S,15aR,16R)- 14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin- 3-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10- sulfidooctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 694 
               
               
                   
               
               
                 281 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5S,7R,8R,12aR,14R,15S,15aR)-14- (4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-15- fluoro-2,10-dihydroxy-2-oxido-10- sulfidooctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one 
                 675 
               
               
                   
               
               
                 282 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 5-amino-3-[(5R,7R,8S,12aR,14R,15S,15aR,16S)- 14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin- 3-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10- sulfidooctahydro-12H-5,8-methanofuro[3,2- 1][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one 
                 695 
               
               
                   
               
               
                 283 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5S,7R,8R,12aR,14R,15aS)-14-(4- aminoimidazo[2,1-f][1,2,4]triazin-7-yl)-2- hydroxy-2,10-dioxido-10-sulfanyloctahydro-12H- 5,8-methanofuro[3,2-1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotctradecin-7-yl]-1,9- dihydro-6H-purin-6-one 
                 657 
               
               
                   
               
               
                 284 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15R,15aS,18R)- 14-(6-amino-9H-purin-9-yl)-18-fluoro-2,10- dihydroxy-2-oxido-10-sulfidohexahydro-14H- 15,12a-(epoxymethano)-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7(12H)-yl]-1,9-dihydro-6H-purin-6-one 
                 719 
               
               
                   
               
               
                 285 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15S,15aR,16R)- 14-(7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin- 3-yl)-15,16-difluoro-2-hydroxy-2,10-dioxido-10- sulfanyloclahydro-12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one 
                 710 
               
               
                   
               
               
                 286 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15S,15aR,16R)- 14-(7-amino-3H-iniidazo[4,5-b]pyridin-3-yl)- 15,16-difluoro-2-hydroxy-2,10-dioxido-10- sulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1) 
                 708 
               
               
                   
               
               
                 287 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15S,15aR,16R)- 14-(7-amino-3H-imidazo[4,5-b]pyridin-3-yl)- 15,16-difluoro-2-hydroxy-2,10-dioxido-10- sulfanyloctahydro-12H-5,8-methanofuro[3,2- 1][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2) 
                 708 
               
               
                   
               
               
                 288 
                 
                   
                     
                     
                         
                         
                     
                   
                 
                 2-amino-9-[(5R,7R,8R,12aR,14R,15aR,16R)-14- (7-amino-3H-[1,2,3]triazolo[4,5-d]pyrimidin-3- yl)-15,15,16-trifluoro-2-hydroxy-2,10-dioxido-10- sulfanyloctahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10]tetraoxathiadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6-one 
                 728 
               
               
                   
               
            
           
         
       
     
     Example 289: 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2,10-disulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     Step 1: N-{9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-2-(2-cyanoethoxy)-15,16-difluoro-10-hydroxy-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purin-6-yl}benzamide 
     
       
         
         
             
             
         
       
     
     O-(((2R,3R,4R,5R)-5-(6-benzamido-9H-purin-9-yl)-4-fluoro-3-hydroxytetrahydrofuran-2-yl)methyl) O-((2R,3S,4R,5R)-4-fluoro-5-(hydroxymethyl)-2-(2-isobutyramido-6-oxo-1H-purin-9(6H)-yl)tetrahydrofuran-3-yl)O-hydrogen phosphorothioate (product of Step 3, Example 261, 100 mg, 0.124 mmol) and diisopropylammonium tetrazolide (31.8 mg, 0.186 mmol) were azeotrope with dry CH 3 CN (3×10 ml) and dried under high vacuum for 30 min. 
     The above mixture was dissolved in DMF (1 mL) and acetonitrile (7 mL) and added 200 mg active MS 4 Å and a solution of 2-cyanoethyl N,N,N′,N′-tetraisopropylphosphorodiamidite (51.1 mg, 0.161 mmol) in 1 ml dry CH 3 CN. The resulting mixture was stirred at rt for 30 min, followed by addition of 1H-tetrazole (43.4 mg, 0.620 mmol). The reaction stayed at rt for 1 h and added tert-butyl hydroperoxide (5.0M in Decane) (0.074 mL, 0.372 mmol). The stirring continued for 1 h and concentrated in vacuo. The residue was purified by column chromatography on silica gel, eluting with 0-8% MeOH/DCM to give the desired product. LCMS (ES, m/z): 922 [M+H] −   
     Step 2: 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     N-{9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-2-(2-cyanoethoxy)-15,16-difluoro-10-hydroxy-7-{2-[(2-methylpropanoyl)amino]-6-oxo-1,6-dihydro-9H-purin-9-yl}-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-14-yl]-9H-purin-6-yl}benzamide (90 mg, 0.098 mmol) and ammonia (7.0M in MeOH) (2 ml, 14.00 mmol) were sealed in a microwave tube. The mixture was heated to 50° C. and stirred for 4 h. The reaction mixture was concentrated, and purified using mass-directed reverse phase HPLC (X-Bridge BEH 150 Prep C18) using a gradient solvent system with MeCN and 100 mM aqueous triethylammonium acetate to give three desired diastereomers. Lyophilization of the product fractions furnished 2-amino-9-[(5R,7R,8S,12aR,14R,15R,15aR,16R)-14-(6-amino-9H-purin-9-yl)-15,16-difluoro-2,10-dihydroxy-2-oxido-10-sulfidooctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one. LCMS (ES, m/z): 693 [M−H] − .  1 H NMR (H2O-d2, 500 MHz): δ H  8.23 (2H, d, J=5.2 Hz), 7.81 (1H, s), 6.42 (1H, d, J=14.2 Hz), 5.99 (1H, d, J=8.6 Hz), 5.70 (1H, m), 5.40 (2H, m), 5.20 (1H, m), 4.62 (2H, m), 4.54 (1H, s), 4.15-4.30 (3H, m).  31 P NMR: (H 2 O-d 2 , 202 MHz): δ −1.6, 52.1. 
     Example 290: 2-amino-9-[1(2R,5S,7R,8R,10R,12aR,14R,15R,15aS)-15-hydroxy-2,10-dioxido-14-(6-oxo-1,6-dihydro-9H-purin-9-yl)-2,10-disulfanyloctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin-7-yl]-1,9-dihydro-6H-purin-6-one 
     
       
         
         
             
             
         
       
     
     To (2R,5S,7R,8R,10R,12aR,14R,15R,15aS)-7-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-14-(6-amino-9H-purin-9-yl)-15-hydroxyoctahydro-12H-5,8-methanofuro[3,2-l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecine-2,10-bis(thiolate) 2,10-dioxide (Example 86, 5.0 mg, 0.0071 mmol) were added sodium phosphate buffer (pH 6.8, 50 mM, 0.5 mL) and adenosine monophosphate deaminase (3 mg). The reaction mixture was left to stir overnight, filtered, and purified by reverse phase HPLC (1-10% MeCN in aq NH 4 HCO 3  (100 mM)) to afford the title compound as a diammonium salt. LCMS (ES, m/z): 690 [M−H] − .  1 H NMR (500 MHz, D 2 O): δ 8.30 (s, 1H), 8.20 (s, 1H), 7.95 (s, 1H), 6.19 (s, 1H), 5.82 (d, J=6.0 Hz, 1H), 5.64 (m, 1H), 5.15 (m, 1H), 4.86 (d, J=4.5 Hz, 1H), 4.60 (m, 1H), 4.48-4.53 (m, 2H), 4.38 (m, 1H), 4.11 (dd, J=11.5, 4.0 Hz, 1H), 4.05 (m, 1H), 2.63 (m, 1H), 2.52 (m, 1H).  31 P NMR: (202 MHz, D 2 O): δ 55.78 (s), 52.44 (s). 
     Examples 291 through 348 as shown in Table 11 below, were prepared according to procedures analogous to those outlined in Example 290 above, from the starting compound (“St. Cmpd.”) indicated. 
                                     TABLE 11                           Mass   St.       Ex.   Structure   Name   [M − H] −     Cmpd.                                                    291                         9-[(5R,7R,8R,12aR,14R,15aS,16R)-7-(6- amino-9H-purin-9-yl)-2,10,16-trihydroxy- 2,10-dioxidooctahydro-12H-5,8- methanofuro[3,2-/][1,3,6,9,11,2,10] pentaoxadiphosphacyclotctradecin-14-yl]- 1,9-dihydro-6H-purin-6-one   642   3               292                         9-[(5R,7R,8R,12aR,14R,15R,15aR,16R)-7 (6-amino-9H-purin-9-yl)-15-fluoro- 2,10,16-trihydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 1,9-dihydro-6H-purin-6-one   660   4               293                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-15- fIuoro-2,10,16-trihydroxy-2,10-dioxido- 14-(6-oxo-1,6-dihydro-9H-purin-9- yl)octahydro-12H-5,8-methanofuro[3,2-1] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   676   2               294                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR)-15- fluoro-2,10-dihydroxy-2,10-dioxido-14- (6-oxo-1,6-dihydro-9H-purin-9- yl)octahydro-12H-5,8-methanofuro[3,2-1] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   660   21               295                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-15- fluoro-2,10,16-trihydroxy-2,10-dioxido- 14-(6-oxo-1,6-dihydro-9H-purin-9- yl)octahydro-12H-5,8-methanofuro[3,2-1] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   676   7               296                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-15- fluoro-2,10,16-trihydroxy-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 1)   708   90               297                         2-amino-9- [(2R,5R,7R,8R,10R,12aR,14R,15S,15aR, 16R)-15-fluoro-2,10,16-trihydroxy-14-(6- oxo-1,6-dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l)[1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 2)   708   89               298                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-15- fluoro-2,10,16-trihydroxy-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 3)   708   91               299                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-15- fluoro-2,10,16-trihydroxy-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofurol]3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 4)   708   92               300                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-16- fluoro-2,10,15-trihydroxy-14-(6-hydroxy- 9H-purin-9-yl)-2,10-dioxidooctahydro- 12H-5,8-methanofuro[3,2-1] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   676   5               301                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)- 2,10,15-trihydroxy-14-(6-hydroxy-9H- purin-9-yl)-16-methoxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   688   13               302                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-16- azido-2,10,15-trihydroxy-14-(6-hydroxy- 9H-purin-9-yl)-2,10-dioxidooctahydro- 12H-5,8-methanofuro[3,2-1] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   699   14               303                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)- 15,16-difluoro-2,10-dihydroxy-10-oxido- 14-(6-oxo-1,6-dihydro-9H-purin-9-yl)-2- sulfidooctahydro-12H-5,8- methanofuro[3,2-/][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   694   143               304                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-15- fluoro-2,10,16-trihydroxy-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   708   81               305                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-16- fluoro-2,10-dihydroxy-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 1)   692   120               306                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aR,16R)-16- fluoro-2,10-dihydroxy-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfidooclahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 2)   692   118               307                         2-amino-9-[(2R,5R,7R,8S,10R, 12aR,14R,15aS,16R)-16-fluoro-2,10- dihydroxy-14-(6-oxo-1,6-dihydro-9H- purin-9-yl)-2,10-disulfidooctahydro-12H- 5,8-methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 3)   692   117               308                         2-amino-9-[(2R,5R,7R,8R,10R, 12aR,14R,15S,15aR,16R)-15,16-difluoro- 2,10-dihydroxy-14-(6-oxo-1,6-dihydro- 9H-purin-9-yl)-2,10-disulfidooctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 1)   710   247               309                         2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dihydroxy-14-(6-oxo- 1,6-dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 2)   710   245               310                         2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dihydroxy-14-(6-oxo- 1,6-dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 3)   710   246               311                         2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dihydroxy-14-(6-oxo- 1,6-dihydro-9H-purin-9-yl)-2,10- disulfidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 4)   710   244               312                         2-amino-9- [(5S,7R,8S,12aR,14R,15S,15aR,16R)-15- fluoro-2,10-dihydroxy-2,10-dioxido-14- (6-oxo-1,6-dihydro-9H-purin-9- yl)octahydro-12H-5,8-methanofuro[3,2-1] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   660   25               313                         2-amino-9-[(5S,7R,8R,12aR,14R,15aS)- 2,10-dihydroxy-2,10-dioxido-14-(6-oxo- l,6-dihydro-9H-purin-9-yl)octahydro- 12H-5,8-methanofuro[3,2-1] [1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   642   27               314                         2-amino-9- [(5R,7R,8S,12aR,14R,15R,15aR,16R)- 15,16-difluoro-2,10-dihydroxy-2,10- dioxido-14-(6-oxo-1,6-dihydro-9H-purin- 9-yl)octahydro-12H-5,8-methanofuro [3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   678    23               315                         2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dihydroxy-2,10- dioxido-14-(6-oxo-1,6-dihydro-9H-purin- 9-yl)octahydro-12H-5,8-methanofuro [3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   678   26               316                         2-amino-9- [(2aR,6aS,7R,8R,9aR,14R,14aS,15R)- 5,7,12-trihydroxy-5,12-dioxido-8-(6-oxo- 1,6-dihydro-9H-purin-9-yl)hexahydro- 6aH-2a,14-(epoxymethano)furo [3,2-d]oxeto[2,3-k][1,3,7,9,2,8] tetraoxadiphosphacyclotridecin- 15(2H,3H)-yl-1,9-dihydro-6H-purin-6- one   686   17               317                         2-amino-9- [(2R,5S,7R,8R,10R,12aR,14R,15S,15aR)- 15-fluoro-2,10-dioxido-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 1)   692   130               318                         2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)-15- fluoro-2,10-dioxido-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 2)   692   131               319                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16S)- 2,10,15,16-tetrahydroxy-2,10-dioxido-14- (6-oxo-1,6-dihydro-9H-purin-9- yl)octahydro-12H-5,8-methanofuro[3,2- l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7- yl]-1,9-dihydro-6H-purin-6-one   690   11               320                         3-[(5R,7R,8S,12aR,14R,15S,15aR,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)- 15-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-1][1,2,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one   693   133               321                         8-[(5R,7R,8R,12aR,14S,15S,15aS,16R)- 7-(2-amino-6-oxo-1,6-dihydro-9H-purin- 9-yl)-2,10,15,16-tetrahydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14- yl]pyrazolo[1,5-a][1,3,5]triazin-4(3H)-one   674   54               322                         2-amino-9-[(5R,7R,8R,,12aR,14R, 15S,15aR,16R)-15-chloro-2,10,16- trihydroxy-2,10-dioxido-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)octahydro-12H- 5,8-methanofuro[3,2-1][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   692   15               323                         2-amino-9-[(2R,5R,7R,8R,10R, 12aR,14R,15S,15aR,16S)-15-fluoro-16- hydroxy-2,10-dioxido-14-(6-oxo-1,6- dihydro-9H-purin-9-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro(3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7- yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 1)   724   97               324                         2-amino-9-[(5R,7R,8R,12aR,14R,15S, 15aR,16S)-15-fluoro-16-hydroxy-2,10- dioxido-14-(6-oxo-1,6-dihydro-9H-purin- 9-yl)-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7- yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 2)   724   99               325                         2-amino-9-[(5R,7R,8R,12aR,14R,15S, 15aR,16S)-15-fIuoro-16-hydroxy-2,10- dioxido-14-(6-oxo-1,6-dihydro-9H-purin- 9-yl)-2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-1][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7- yl]-1,9-dihydro-6H-purin-6-one (Diastereomer 3)   724   96               326                         3-[(5R,7R,8S,12aR,14R,15S,15aR,16R)- 7-(2-amino-6-oxo-1,6-dihydro-9H-purin- 9-yl)-15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1)   711   130               327                         3-[(5R,7R,8S,12aR,14R,15S,15aR,16R)- 7-(2-amino-6-oxo-1,6-dihydro-9H-purin- 9-yl)-15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2)   711   128               328                         3-[(5R,7R,8S,12aR,14R,15S,15aR,16R)- 7-(2-amino-6-oxo-1,6-dihydro-9H-purin- 9-yl)-15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5.8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 3)   711   127               329                         2-amino-9-[(2R,5R,7R,8S,10R, 12aR,14R,15S,15aR,16S)-15,16-difluoro- 2,10-dioxido-14-(6-oxo-1,6-dihydro-9H- purin-9-yl)-2,10-disulfanyloctahydro- 12H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 1)   710   144               330                         2-amino-9-[(5R,7R,8S,12aR,14R,15S, 15aR,16R)-15,16-difluoro-2,10-dioxido- 14-(6-oxo-1,6-dihydro-9H-purin-9-yl)- 2,10-disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one (Diastereomer 2)   710   145               331                         3-[(5R,7R,8S,12aR,14R,15S,15aR,16S)- 7-(2-amino-6-oxo-1,6-dihydro-9H-purin- 9-yl)-15,16-difluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one   711   147               332                         2-amino-9- [(5R,7R,8S,12aR,14R,15aS,16R)-16- fluoro-2,10-dihydroxy-2,10-dioxido-14- (6-oxo-1,6-dihydro-9H-purin-9- yl)octahydro-l2H-5,8-methanofuro[3,2- l][1,3,6,9,11,2,10]pentaoxadiphosphacyclotetradecin- 7-yl]-1,9-dihydro-6H-purin-6- one   660   22               333                         9,9&#39;-[(5R,7R,8S,12aR,14R,15R,15aS)- 2,10,15-trihydroxy-2,10- dioxidooctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecine-7,14- diyl]bis(1,9-dihydro-6H-purin-6-one)   643   50               334                         2-amino-9- [(5R,7R,8R,12aR,14R,15R,15aS,16R)- 10,15,16-trihydroxy-2,10-dioxido-14-(6- oxo-1,6-dihydro-9H-purin-9-yl)-2- sulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   690   38               335                         2-amino-9- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dioxido-14-(6-oxo- 1,6-dihydro-9H-purin-9-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 1,9-dihydro-6H-purin-6-one   710   260               336                         7-[(5R,7R,8S,12aR,14R,15aS,15aR,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)- 16-fluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14- yl]imidazo[2,1-f][1,2,4]triazin-4(3H)-one (Diastereomer 1)   692   249               337                         3-[(5R,7R,8S,12aR,14R,15aR,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)- 15,15,16-trifluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1)   729   165               338                         3-[(5R,7R,8S,12aR,14R,15aR,16R)-7-(2- amino-6-oxo-1,6-dihydro-9H-purin-9-yl)- 15,15,16-trifluoro-2,10-dioxido-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2)   729   167               339                         2-amino-9- [(5R,7R,8R,12aR,14R,15S,15aR,16S)-15- fluoro-2,16-dihydroxy-2,10-dioxido-14- (6-oxo-1,6-dihydro-9H-purin-9-yl)-10- sulfanyloctahydro-12H-5,8- methanofuro[3,2-1][1,3,9,11,6,2,10] tetraoxathiadiphosphacyclotetradecin-7- yl]-1,9-dihydro-6H-purin-6-one   708   266               340                         5-amino-3- [(5R,7R,8R,12aR,14R,15S,15aR)-15- fluoro-2,10-dioxido-14-(7-oxo-6,7- dihydro-3H-[1,2,3]triazolo[4,5- d]pyrimidin-3-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1)   694   181               341                         5-amino-3- [(5S,7R,8R,12aR,14R,15S,15aR)-15- fluoro-2,10-dioxido-14-(7-oxo-6,7- dihydro-3H-[1,2,3]triazolo[4,5- d]pyrimidin-3-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2)   694   182               342                         5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dioxido-14-(6-oxo- 1,6-dihydro-9H-purin-9-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1)   711   199               343                         5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dioxido-14-(6-oxo- 1,6-dihydro-9H-purin-9-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2)   711   197               344                         5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dioxido-14-(7-oxo- 6,7-dihydro-3H-[1,2,3]triazolo[4,5- d]pyrimidin-3-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1)   712   200               345                         5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16R)- 15,16-difluoro-2,10-dioxido-14-(7-oxo- 6,7-dihydro-3H-[1,2,3]triazolo[4,5- d]pyrimidin-3-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2)   712   201               346                         3-[(5R,7R,8S,12aR,14R,15S,15aR,16R)- 7-(2-amino-6-oxo-1,6-dihydro-9H-purin- 9-yl)-15,16-difluoro-2-hydroxy-2,10- dioxido-10-sulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 1)   695   279               347                         3-[(5R,7R,8S,12aR,14R,15S,15aR,16R)- 7-(2-amino-6-oxo-1,6-dihydro-9H-purin- 9-yl)-15,16-difluoro-2-hydroxy-2,10- dioxido-10-sulfanyloctahydro-12H-5,8- methanofuro(3,2-l)[1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-14-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one (Diastereomer 2)   695   280               348                         5-amino-3- [(5R,7R,8S,12aR,14R,15S,15aR,16S)- 15,16-difluoro-2,10-dioxido-14-(6-oxo- 1,6-dihydro-9H-purin-9-yl)-2,10- disulfanyloctahydro-12H-5,8- methanofuro[3,2-l][1,3,6,9,11,2,10] pentaoxadiphosphacyclotetradecin-7-yl]- 3,6-dihydro-7H-[1,2,3]triazolo[4,5- d]pyrimidin-7-one   711   179                    
Biological Evaluation
 
     The individual compounds described in the Examples are defined as STING agonists by demonstrating binding to the STING protein with an EC 50  of 20 uM or less in the STING Biochemical [ 3 H]cGAMP Competition Assay (using either HAQ or wild type (WT) STING) and demonstrating interferon production with a 5% or greater luminescence induction at 30 uM in the INF-β secretion in the THP1 cell assay. The methods below describe each of these assays. 
     [ 3 H]-cGAMP Synthesis 
     2.3 mL of buffer solution containing 80 mM tris Cl, 200 mM MgCl 2  and 20 mM NaCl followed by 0.32 mL of a 10 mM aq solution of GTP was added to a plastic 50 mL AMICON tube. A solution of [ 3 H]ATP (21Ci/mmol, 45 mCi) in 0.5 mL H 2 O was then added followed by 1 mL of a 1 mg/mL solution of DNA (Herring testes activator DNA, Sigma, # D6898) and 53 uL of a 47 mM solution of cGAS enzyme. Additional H 2 O was added to bring the total volume to 10 mL. 
     The reaction was stirred for 2 h at 37° C. and then added directly to an Amicon Ultra-15 10K centrifuge tube and spun for 1 h at 4,000 g. The collected solution was then purified on a semi-prep Mono Q column using the following mobile phases:
         A: 0.05M TrisCl pH 8.5 adjusted with 1M NaOH   B: 0.05M TrisCl, 0.5M NaCl pH 8.5 adjusted with 1M NaOH       

     Gradient: 100% A for 5 min followed by a linear gradient to 50:50 (A:B) over 25 min, 3 mL/min, 254 nm. 
     The collected product fractions were pooled and adjusted to a total volume of 30 mL with buffer A. A total yield of 15.5 mCi of [ 3 H]cGAMP was isolated at a radiochemical purity of 98.0% at a specific activity of 21.5Ci/mmol. 
     cGAS Enzyme 
     A recombinant DNA vector was chemically synthesized to express the truncated human cGAS enzyme (residues 161-522). To aid in expression and purification, the amino terminus contains a hexahistidine tag, SUMO tag and TEV cleavage site. The recombinant enzyme was overexpressed in ROSETTA™ 2(DE3) Single Competent Cells (Novagen). Affinity purification was carried out using HIS-Select HF Nickel Affinity Gel (Sigma) followed by size exclusion chromatography using a Hi-Load 26/60 SUPERDEX200 prep grade column (GE Healthcare). Fractions were pooled, concentrated, flash frozen in liquid nitrogen and stored at −80° C. until needed for research applications. 
     Example 349:  3 H-cGAMP Filtration Binding Assay (HAQ STING) 
     The ability of compounds to bind STING is quantified by their ability to compete with tritiated cGAMP ligand for human STING receptor membrane using a radioactive filter-binding assay. The binding assay employs STING receptor obtained from  Trichoplusia ni  cell membranes ( T. ni ; Expression Systems, cat #94-002F, www.expressionsystems.com) overexpressing full-length HAQ STING prepared in-house and tritiated cGAMP ligand also purified in-house. 
     The basic HAQ STING filtration assay protocol is as follows: 
     The compounds were serially titrated by the Hamilton STARPlus CORE in a 96-well plate (Greiner, #651201) using a 1:3 ten-point dose response format. After compound preparation, a 2.2 ug/ml working concentration of STING membrane (SEQ. ID. No. 2) was prepared by diluting concentrated membrane into assay buffer (lx PBS; Invitrogen # SH30028.02) and douncing 7× using a manual tissue homogenizer (Wheaton, #357546). 148 uL of prepared membrane was then manually added to each well of a 96-well deep-well polypropylene plate (Fisher Scientific, #12-566-121). Following membrane addition, 2 uL of either titrated test compound, DMSO control (Sigma #276855), or cold cGAMP control (prepared in-house) was added to the appropriate wells using a Biomek FX. Compound and membrane then preincubated for 60 min at RT to allow compound binding to equilibrate. Following equilibration, 8 nM of [ 3 H]c-GAMP ligand was prepared by diluting into assay buffer, and 50 uL of this working stock was then manually added to each well of the assay plate. Plates were then incubated at RT for 60 min, and the contents of each assay plate were then filtered through a 96-well GF/B filter plate (PerkinElmer, #6005250) using a TomTec MachIII Cell Harvester equipped with 20 mM HEPES buffer (Fisher Scientific, # BP299500). The filter plates were then dried at 55° C. for 30 min using a pressurized VWR oven before 30 uL of Ultima GoldF scintillate was added to each well. Tritium levels for each reaction well were then measured using a PerkinElmer TopCount plate reader. 
     After normalization to controls, the percent activity for each compound concentration was calculated by measuring the amount of remaining radioactivity. The plot of percent activity versus the log of compound concentration was fit with a 4-parameter dose response equation to calculate EC 50  values. 
     The final reaction conditions were: 
     
       
         
           
               
               
               
             
               
                   
               
               
                 Component 
                 Volume (uL) 
                 Final Concentration 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 STING membrane 
                 148 
                 1.5 
                 ug/ml 
               
               
                   3 H-cGAMP 
                 50 
                 2.0 
                 nM 
               
               
                 Low Control (cold cGAMP) 
                 2 
                 10 
                 uM 
               
               
                 Test compound/DMSO 
                 2 
                 10 
                 uM 
               
               
                   
               
            
           
         
       
     
     Compound concentrations tested were 20.000, 637.00, 2.200, 0.740, 0.247, 0.082, 0.027, 0.009, 0.003, and 0.001 μM with 1.0% residual DMSO. 
     Full-Length STING (HAQ) Virus Generation 
     STING virus was generated using an insect cell baculovirus system.  Spodoptera frugiperda  Sf21 cells (Kempbio, Inc.) were diluted to 5e5 cells/ml in Sf-900II SFM media (LifeTechnologies #10902088) without antibiotics. The cell suspension was added to each well of a treated 6-well plate (2 mL per well, 1e6 cells total), and the cells were allowed to adhere for at least 30 min. Meanwhile, a 1 mL co-transfection mix was assembled by combining 500 ng of HAQ STING [STING(1-379)R71H,G230 Å,H232R,R293Q-GG-AviTag-GS-HRV3C-HIS8/pBAC1] DNA (Genewiz custom synthesis) with 1 mL Sf-900II SFM media containing 10 μL Cellfectin® II Reagent (Invitrogen #10362100) and 100 ng viral backbone BestBac 2.0, v-cath/chiA Deleted Linearized Baculovirus DNA (Expression Systems #91-002). The transfection mixtures were allowed to incubate for 30 min. After incubation, media was gently removed from the adhered cells in the 6-well plate, the 1 mL transfection mixtures were added (1 mL per well), and the plate was placed in a humidified incubator at 27° C. The following day, 1 mL Sf-900II SFM media (no antibiotics) was added to each well of the 6-well plate. After media addition, the cells were allowed to incubate with DNA (SEQ. ID. No. 3) at 27° C. for 5-7 days to generate the P0 viral stock. To generate P1 viral stocks, 0.5 mL of P0 viral supernatant was added to 50 mL uninfected Sf21 cells (seeded the day prior to infection at a density of 5×10 5  cells/mL to allow for one overnight doubling) in Sf-900II SFM media containing 5 g/mL gentamicin (Invitrogen #15710072). The infected cells were then incubated at 27° C. for 3d while shaking at 110 rpm (ATR Biotech Multitron Infors HT # AJ118). On day 3, P1 cultures were counted using a ViCell XR (Beckman Coulter Life Sciences #383556) to confirm infection had occurred (cell size ≥3 μm larger than uninfected cells and viability approximately 85-95%). Cultures were harvested in 50 mL conical tubes and centrifuged at 2000×g for 10 min at 4° C. The P1 viral supernatants were poured off into clean 50 ml centrifuge tubes, and the remaining P1 cell pellets were used to generate Baculovirus Infected Insect Cells (BIICs) according to in-house validated SOP. Cryopreservation media containing Sf-900II SFM media with 10% heat inactivated FBS, 10% DMSO (Sigma # D2650), and 5 μg/ml gentamicin was prepared in-house and sterilized through 0.22 μM filter immediately prior to use. P1 cell pellets were resuspended to a density of 2e7 cells/ml and aliquoted into cryovials (1 mL per vial). Cryovials were placed in Mr. Frosty cell freezers O/N at −80° C. and transferred to liquid nitrogen for long term storage the following day. To generate P2 viral stock, 0.5 mL of the P1 viral supernatant was added to 50 mL uninfected Sf21 cells (seeded the day prior to infection at a density of 5×10 5  cells/mL to allow for one overnight doubling) in Sf-900II SFM media containing 5 μg/mL gentamicin. These cells were incubated at 27° C. for 3d while shaking at 110 rpm before harvesting P2 stock with centrifugation at 2000×g for 10 min at 4° C. The P2 viral supernatants were poured off and discarded, while the P2 cell pellets were used to generate P2 BIICs following the same protocol described above. The baculovirus generation protocol has been validated to consistently produce P1/P2 BIICs with titers of 2e9 pfu/mL (2e7 cells/mL×100 pfu/cell). 
     Full-Length STING (HAQ) Expression 
     To generate STING membranes, P1/P2 BIICs were amplified overnight by adding thawed BIICs to Sf21 cells seeded at a density of 1.0×10 6  cells/mL. The volume of BIIC used to infect the culture was calculated using an assumed BIIC titer of 2e9 pfu/ml to achieve an MOI of 10 in the overnight amplification. After culturing overnight, the cells were counted on a ViCell XR to confirm infection had occurred (cell size ≥3 μm larger than uninfected cells and viability approximately 80-90%). The volume of infected Sf21 cells from the overnight amplification used to infect the large-scale expression of  Trichoplusia ni  ( T. ni ; Expression Systems, cat #94-002F, www.expressionsystems.com) seeded at a density of 1.0×10 6  in cell media (ESF921 SFM containing 5 μg/mL gentamicin) at MOI=2.0 was calculated based on (100 pfu/infected Sf21 cell). The cells were allowed to express for 48 h at 27° C. before harvesting the cell pellet, by centrifugation at 3,400×g for 10 min at 4° C.  T. ni  cells were counted on a ViCell XR to confirm infection had occurred (cell size ≥3 μm larger than uninfected cells and viability approximately 80-90%) prior to harvest. 
     Full-Length STING (HAQ) Membrane Generation 
     Buffer stock reagents: 
     
         
         
           
             1) 1 M HEPES pH 7.5, Teknova, Cat # H1035 
             2) 5 M NaCl, Sigma Aldrich, Cat # S5150-1 L 
             3) KCl, Sigma Aldrich, Cat #319309-500ML 
             4) Complete EDTA-free protease inhibitor tablets, Roche Diagnostics, Cat #11873580001 
             5) Benzonase, Universal Nuclease, Pierce, Cat #88702 
           
         
       
    
     Lysis buffer [25 mM HEPES pH 7.5, 10 mM MgCl 2 , 20 mM KCl, (Benzonase 1:5000, Complete Protease Inhibitor tab/50 mL)] was added to the pellet of cells expressing full-length STING (HAQ) prepared above at 5 mL Lysis buffer/g of cell pellet. The pellet was resuspended and dounced twenty times using a Wheaton Dounce Homogenizer to disrupt the cell membrane. Homogenized lysate was then passed through the emulsiflex-C 5  microfluidizer at a pressure close to 5000 PSI. The resuspended pellet was centrifuged at 36,000 rpm (100,000×g) in a 45Ti rotor in the ultra-high speed centrifuge for 45 min, 4° C. The supernatant was removed. The pellet then was resuspended in wash buffer [(25 mM HEPES pH7.5, 1 mM MgCl 2 , 20 mM KCl, 1M NaCl (Complete Protease Inhibitor tab/50 mL)] at a volume of 50 mL pellet/centrifuge tube. The pellet/wash buffer mixture was then homogenized, using a glass homogenizer on ice (20 strokes), followed by centrifugation at 36,000 rpm for 45 min at 4° C. The supernatant was removed. The wash step was repeated once more. The resulting membrane was resuspended in 20 mM HEPES pH 7.5, 500 mM NaCl, 10% glycerol, EDTA-free Protease Inhibitors (1 tablet/50 mL). The protein concentration was measured by Bradford assay (Bio-Rad Protein Assay, Cat #500-0006), and protein enrichment was determined by SDS-PAGE and confirmed by Western blot. The resuspended membranes were stored at −80° C. 
     Full-Length HAQ STING [STING(1-379)R71H, G230 Å,H232R, R293Q-GG-AviTag-GS-HRV3C-HIS8]Amino Acid Sequence. 
                    (SEQ. ID. No. 2)       MPHSSLHPSIPCPRGHGAQKAALVLLSACLVTLWGLGEPPEHTLRYLVLH               LASLQLGLLLNGVCSLAEELHHIHSRYRGSYWRTVRACLGCPLRRGALLL               LSIYFYYSLPNAVGPPFTWMLALLGLSQALNILLGLKGLAPAEISAVCEK               GNFNVAHGLAWSYYIGYLRLILPELQARIRTYNQHYNNLLRGAVSQRLYI               LLPLDCGVPDNLSMADPNIRFLDKLPQQTADRAGIKDRVYSNSIYELLEN               GQRAGTCVLEYATPLQTLFAMSQYSQAGFSREDRLEQAKLFCQTLEDILA               DAPESQNNCRLIAYQEPADDSSFSLSQEVLRHLRQEEKEEVTVGSLKTSA               VPSTSTMSQEPELLISGMEKPLPLRTDFSGGGLNDIFEAQKIEWHEGSLE               VLFQGPHHHHHHHH            
Full-length HAQ [STING(1-379)R71H, G230 Å,H232R,R293Q-GG-AviTag-GS-HRV3C-HIS8/pBAC1] Plasmid DNA Sequence:
 
     
       
         
           
               
            
               
                 (SEQ. ID. No. 3) 
               
               
                 GGAACGGCTCCGCCCACTATTAATGAAATTAAAAATTCCAATTTTAAAAA 
               
               
                   
               
               
                 ACGCAGCAAGAGAAACATTTGTATGAAAGAATGCGTAGAAGGAAAGAAAA 
               
               
                   
               
               
                 ATGTCGTCGACATGCTGAACAACAAGATTAATATGCCTCCGTGTATAAAA 
               
               
                   
               
               
                 AAAATATTGAACGATTTGAAAGAAAACAATGTACCGCGCGGCGGTATGTA 
               
               
                   
               
               
                 CAGGAAGAGGTTTATACTAAACTGTTACATTGCAAACGTGGTTTCGTGTG 
               
               
                   
               
               
                 CCAAGTGTGAAAACCGATGTTTAATCAAGGCTCTGACGCATTTCTACAAC 
               
               
                   
               
               
                 CACGACTCCAAGTGTGTGGGTGAAGTCATGCATCTTTTAATCAAATCCCA 
               
               
                   
               
               
                 AGATGTGTATAAACCACCAAACTGCCAAAAAATGAAAACTGTCGACAAGC 
               
               
                   
               
               
                 TCTGTCCGTTTGCTGGCAACTGCAAGGGTCTCAATCCTATTTGTAATTAT 
               
               
                   
               
               
                 TGAATAATAAAACAATTATAAATGCTAAATTTGTTTTTTATTAACGATAC 
               
               
                   
               
               
                 AAACCAAACGCAACAAGAACATTTGTAGTATTATCTATAATTGAAAACGC 
               
               
                   
               
               
                 GTAGTTATAATCGCTGAGGTAATATTTAAAATCATTTTCAAATGATTCAC 
               
               
                   
               
               
                 AGTTAATTTGCGACAATATAATTTTATTTTCACATAAACTAGACGCCTTG 
               
               
                   
               
               
                 TCGTCTTCTTCTTCGTATTCCTTCTCTTTTTCATTTTTCTCTTCATAAAA 
               
               
                   
               
               
                 ATTAACATAGTTATTATCGTATCCATATATGTATCTATCGTATAGAGTAA 
               
               
                   
               
               
                 ATTTTTTGTTGTCATAAATATATATGTCTTTTTTAATGGGGTGTATAGTA 
               
               
                   
               
               
                 CCGCTGCGCATAGTTTTTCTGTAATTTACAACAGTGCTATTTTCTGGTAG 
               
               
                   
               
               
                 TTCTTCGGAGTGTGTTGCTTTAATTATTAAATTTATATAATCAATGAATT 
               
               
                   
               
               
                 TGGGATCGTCGGTTTTGTACAATATGTTGCCGGCATAGTACGCAGCTTCT 
               
               
                   
               
               
                 TCTAGTTCAATTACACCATTTTTTAGCAGCACCGGATTAACATAACTTTC 
               
               
                   
               
               
                 CAAAATGTTGTACGAACCGTTAAACAAAAACAGTTCACCTCCCTTTTCTA 
               
               
                   
               
               
                 TACTATTGTCTGCGAGCAGTTGTTTGTTGTTAAAAATAACAGCCATTGTA 
               
               
                   
               
               
                 ATGAGACGCACAAACTAATATCACAAACTGGAAATGTCTATCAATATATA 
               
               
                   
               
               
                 GTTGCTGATCAGATCTGATCATGGAGATAATTAAAATGATAACCATCTCG 
               
               
                   
               
               
                 CAAATAAATAAGTATTTTACTGTTTTCGTAACAGTTTTGTAATAAAAAAA 
               
               
                   
               
               
                 CCTATAAATATAGGATCCATGCCCCACTCCAGCCTGCATCCATCCATCCC 
               
               
                   
               
               
                 GTGTCCCAGGGGTCACGGGGCCCAGAAGGCAGCCTTGGTTCTGCTGAGTG 
               
               
                   
               
               
                 CCTGCCTGGTGACCCTTTGGGGGCTAGGAGAGCCACCAGAGCACACTCTC 
               
               
                   
               
               
                 CGGTACCTGGTGCTCCACCTAGCCTCCCTGCAGCTGGGACTGCTGTTAAA 
               
               
                   
               
               
                 CGGGGTCTGCAGCCTGGCTGAGGAGCTGCACCACATCCACTCCAGGTACC 
               
               
                   
               
               
                 GGGGCAGCTACTGGAGGACTGTGCGGGCCTGCCTGGGCTGCCCCCTCCGC 
               
               
                   
               
               
                 CGTGGGGCCCTGTTGCTGCTGTCCATCTATTTCTACTACTCCCTCCCAAA 
               
               
                   
               
               
                 TGCGGTCGGCCCGCCCTTCACTTGGATGCTTGCCCTCCTGGGCCTCTCGC 
               
               
                   
               
               
                 AGGCACTGAACATCCTCCTGGGCCTCAAGGGCCTGGCCCCAGCTGAGATC 
               
               
                   
               
               
                 TCTGCAGTGTGTGAAAAAGGGAATTTCAACGTGGCCCATGGGCTGGCATG 
               
               
                   
               
               
                 GTCATATTACATCGGATATCTGCGGCTGATCCTGCCAGAGCTCCAGGCCC 
               
               
                   
               
               
                 GGATTCGAACTTACAATCAGCATTACAACAACCTGCTACGGGGTGCAGTG 
               
               
                   
               
               
                 AGCCAGCGGCTGTATATTCTCCTCCCATTGGACTGTGGGGTGCCTGATAA 
               
               
                   
               
               
                 CCTGAGTATGGCTGACCCCAACATTCGCTTCCTGGATAAACTGCCCCAGC 
               
               
                   
               
               
                 AGACCGCTGACCGTGCTGGCATCAAGGATCGGGTTTACAGCAACAGCATC 
               
               
                   
               
               
                 TATGAGCTTCTGGAGAACGGGCAGCGGGCGGGCACCTGTGTCCTGGAGTA 
               
               
                   
               
               
                 CGCCACCCCCTTGCAGACTTTGTTTGCCATGTCACAATACAGTCAAGCTG 
               
               
                   
               
               
                 GCTTTAGCCGGGAGGATAGGCTTGAGCAGGCCAAACTCTTCTGCCAGACA 
               
               
                   
               
               
                 CTTGAGGACATCCTGGCAGATGCCCCTGAGTCTCAGAACAACTGCCGCCT 
               
               
                   
               
               
                 CATTGCCTACCAGGAACCTGCAGATGACAGCAGCTTCTCGCTGTCCCAGG 
               
               
                   
               
               
                 AGGTTCTCCGGCACCTGCGGCAGGAGGAAAAGGAAGAGGTTACTGTGGGC 
               
               
                   
               
               
                 AGCTTGAAGACCTCAGCGGTGCCCAGTACCTCCACGATGTCCCAAGAGCC 
               
               
                   
               
               
                 TGAGCTCCTCATCAGTGGAATGGAAAAGCCCCTCCCTCTCCGCACGGATT 
               
               
                   
               
               
                 TCTCTGGCGGTGGCCTGAACGACATCTTCGAAGCCCAGAAAATCGAATGG 
               
               
                   
               
               
                 CATGAAGGCAGCCTGGAAGTGCTGTTCCAGGGCCCACACCACCATCATCA 
               
               
                   
               
               
                 CCATCACCATTAATGAGCGGCCGCACTCGAGCACCACCACCACCACCACT 
               
               
                   
               
               
                 AACCTAGGTAGCTGAGCGCATGCAAGCTGATCCGGGTTATTAGTACATTT 
               
               
                   
               
               
                 ATTAAGCGCTAGATTCTGTGCGTTGTTGATTTACAGACAATTGTTGTACG 
               
               
                   
               
               
                 TATTTTAATAATTCATTAAATTTATAATCTTTAGGGTGGTATGTTAGAGC 
               
               
                   
               
               
                 GAAAATCAAATGATTTTCAGCGTCTTTATATCTGAATTTAAATATTAAAT 
               
               
                   
               
               
                 CCTCAATAGATTTGTAAAATAGGTTTCGATTAGTTTCAAACAAGGGTTGT 
               
               
                   
               
               
                 TTTTCCGAACCGATGGCTGGACTATCTAATGGATTTTCGCTCAACGCCAC 
               
               
                   
               
               
                 AAAACTTGCCAAATCTTGTAGCAGCAATCTAGCTTTGTCGATATTCGTTT 
               
               
                   
               
               
                 GTGTTTTGTTTTGTAATAAAGGTTCGACGTCGTTCAAAATATTATGCGCT 
               
               
                   
               
               
                 TTTGTATTTCTTTCATCACTGTCGTTAGTGTACAATTGACTCGACGTAAA 
               
               
                   
               
               
                 CACGTTAAATAGAGCTTGGACATATTTAACATCGGGCGTGTTAGCTTTAT 
               
               
                   
               
               
                 TAGGCCGATTATCGTCGTCGTCCCAACCCTCGTCGTTAGAAGTTGCTTCC 
               
               
                   
               
               
                 GAAGACGATTTTGCCATAGCCACACGACGCCTATTAATTGTGTCGGCTAA 
               
               
                   
               
               
                 CACGTCCGCGATCAAATTTGTAGTTGAGCTTTTTGGAATTATTTCTGATT 
               
               
                   
               
               
                 GCGGGCGTTTTTGGGCGGGTTTCAATCTAACTGTGCCCGATTTTAATTCA 
               
               
                   
               
               
                 GACAACACGTTAGAAAGCGATGGTGCAGGCGGTGGTAACATTTCAGACGG 
               
               
                   
               
               
                 CAAATCTACTAATGGCGGCGGTGGTGGAGCTGATGATAAATCTACCATCG 
               
               
                   
               
               
                 GTGGAGGCGCAGGCGGGGCTGGCGGCGGAGGCGGAGGCGGAGGTGGTGGC 
               
               
                   
               
               
                 GGTGATGCAGACGGCGGTTTAGGCTCAAATGTCTCTTTAGGCAACACAGT 
               
               
                   
               
               
                 CGGCACCTCAACTATTGTACTGGTTTCGGGCGCCGTTTTTGGTTTGACCG 
               
               
                   
               
               
                 GTCTGAGACGAGTGCGATTTTTTTCGTTTCTAATAGCTTCCAACAATTGT 
               
               
                   
               
               
                 TGTCTGTCGTCTAAAGGTGCAGCGGGTTGAGGTTCCGTCGGCATTGGTGG 
               
               
                   
               
               
                 AGCGGGCGGCAATTCAGACATCGATGGTGGTGGTGGTGGTGGAGGCGCTG 
               
               
                   
               
               
                 GAATGTTAGGCACGGGAGAAGGTGGTGGCGGCGGTGCCGCCGGTATAATT 
               
               
                   
               
               
                 TGTTCTGGTTTAGTTTGTTCGCGCACGATTGTGGGCACCGGCGCAGGCGC 
               
               
                   
               
               
                 CGCTGGCTGCACAACGGAAGGTCGTCTGCTTCGAGGCAGCGCTTGGGGTG 
               
               
                   
               
               
                 GTGGCAATTCAATATTATAATTGGAATACAAATCGTAAAAATCTGCTATA 
               
               
                   
               
               
                 AGCATTGTAATTTCGCTATCGTTTACCGTGCCGATATTTAACAACCGCTC 
               
               
                   
               
               
                 AATGTAAGCAATTGTATTGTAAAGAGATTGTCTCAAGCTCGGATCGATCC 
               
               
                   
               
               
                 CGCACGCCGATAACAAGCCTTTTCATTTTTACTACAGCATTGTAGTGGCG 
               
               
                   
               
               
                 AGACACTTCGCTGTCGTCGAGGTTTAAACGCTTCCTCGCTCACTGACTCG 
               
               
                   
               
               
                 CTGCGCTCGGTCGTTCGGCTGCGGCGAGCGGTATCAGCTCACTCAAAGGC 
               
               
                   
               
               
                 GGTAATACGGTTATCCACAGAATCAGGGGATAACGCAGGAAAGAACATGT 
               
               
                   
               
               
                 GAGCAAAAGGCCAGCAAAAGGCCAGGAACCGTAAAAAGGCCGCGTTGCTG 
               
               
                   
               
               
                 GCGTTTTTCCATAGGCTCCGCCCCCCTGACGAGCATCACAAAAATCGACG 
               
               
                   
               
               
                 CTCAAGTCAGAGGTGGCGAAACCCGACAGGACTATAAAGATACCAGGCGT 
               
               
                   
               
               
                 TTCCCCCTGGAAGCTCCCTCGTGCGCTCTCCTGTTCCGACCCTGCCGCTT 
               
               
                   
               
               
                 ACCGGATACCTGTCCGCCTTTCTCCCTTCGGGAAGCGTGGCGCTTTCTCA 
               
               
                   
               
               
                 TAGCTCACGCTGTAGGTATCTCAGTTCGGTGTAGGTCGTTCGCTCCAAGC 
               
               
                   
               
               
                 TGGGCTGTGTGCACGAACCCCCCGTTCAGCCCGACCGCTGCGCCTTATCC 
               
               
                   
               
               
                 GGTAACTATCGTCTTGAGTCCAACCCGGTAAGACACGACTTATCGCCACT 
               
               
                   
               
               
                 GGCAGCAGCCACTGGTAACAGGATTAGCAGAGCGAGGTATGTAGGCGGTG 
               
               
                   
               
               
                 CTACAGAGTTCTTGAAGTGGTGGCCTAACTACGGCTACACTAGAAGGACA 
               
               
                   
               
               
                 GTATTTGGTATCTGCGCTCTGCTGAAGCCAGTTACCTTCGGAAAAAGAGT 
               
               
                   
               
               
                 TGGTAGCTCTTGATCCGGCAAACAAACCACCGCTGGTAGCGGTGGTTTTT 
               
               
                   
               
               
                 TTGTTTGCAAGCAGCAGATTACGCGCAGAAAAAAAGGATCTCAAGAAGAT 
               
               
                   
               
               
                 CCTTTGATCTTTTCTACGGGGTCTGACGCTCAGTGGAACGAAAACTCACG 
               
               
                   
               
               
                 TTAAGGGATTTTGGTCATGAGATTATCAAAAAGGATCTTCACCTAGATCC 
               
               
                   
               
               
                 TTTTAAATTAAAAATGAAGTTTTAAATCAATCTAAAGTATATATGAGTAA 
               
               
                   
               
               
                 ACTTGGTCTGACAGTTACCAATGCTTAATCAGTGAGGCACCTATCTCAGC 
               
               
                   
               
               
                 GATCTGTCTATTTCGTTCATCCATAGTTGCCTGACTCCCCGTCGTGTAGA 
               
               
                   
               
               
                 TAACTACGATACGGGAGGGCTTACCATCTGGCCCCAGTGCTGCAATGATA 
               
               
                   
               
               
                 CCGCGAGACCCACGCTCACCGGCTCCAGATTTATCAGCAATAAACCAGCC 
               
               
                   
               
               
                 AGCCGGAAGGGCCGAGCGCAGAAGTGGTCCTGCAACTTTATCCGCCTCCA 
               
               
                   
               
               
                 TCCAGTCTATTAATTGTTGCCGGGAAGCTAGAGTAAGTAGTTCGCCAGTT 
               
               
                   
               
               
                 AATAGTTTGCGCAACGTTGTTGCCATTGCTACAGGCATCGTGGTGTCACG 
               
               
                   
               
               
                 CTCGTCGTTTGGTATGGCTTCATTCAGCTCCGGTTCCCAACGATCAAGGC 
               
               
                   
               
               
                 GAGTTACATGATCCCCCATGTTGTGCAAAAAAGCGGTTAGCTCCTTCGGT 
               
               
                   
               
               
                 CCTCCGATCGTTGTCAGAAGTAAGTTGGCCGCAGTGTTATCACTCATGGT 
               
               
                   
               
               
                 TATGGCAGCACTGCATAATTCTCTTACTGTCATGCCATCCGTAAGATGCT 
               
               
                   
               
               
                 TTTCTGTGACTGGTGAGTACTCAACCAAGTCATTCTGAGAATAGTGTATG 
               
               
                   
               
               
                 CGGCGACCGAGTTGCTCTTGCCCGGCGTCAATACGGGATAATACCGCGCC 
               
               
                   
               
               
                 ACATAGCAGAACTTTAAAAGTGCTCATCATTGGAAAACGTTCTTCGGGGC 
               
               
                   
               
               
                 GAAAACTCTCAAGGATCTTACCGCTGTTGAGATCCAGTTCGATGTAACCC 
               
               
                   
               
               
                 ACTCGTGCACCCAACTGATCTTCAGCATCTTTTACTTTCACCAGCGTTTC 
               
               
                   
               
               
                 TGGGTGAGCAAAAACAGGAAGGCAAAATGCCGCAAAAAAGGGAATAAGGG 
               
               
                   
               
               
                 CGACACGGAAATGTTGAATACTCATACTCTTCCTTTTTCAATATTATTGA 
               
               
                   
               
               
                 AGCATTTATCAGGGTTATTGTCTCATGAGCGGATACATATTTGAATGTAT 
               
               
                   
               
               
                 TTAGAAAAATAAACAAATAGGGGTTCCGCGCACATTTCCCCGAAAAGTGC 
               
               
                   
               
               
                 CACCTGACGCGCCCTGTAGCGGCGCATTAAGCGCGGCGGGTGTGGTGGTT 
               
               
                   
               
               
                 ACGCGCAGCGTGACCGCTACACTTGCCAGCGCCCTAGCGCCCGCTCCTTT 
               
               
                   
               
               
                 CGCTTTCTTCCCTTCCTTTCTCGCCACGTTCGCCGGCTTTCCCCGTCAAG 
               
               
                   
               
               
                 CTCTAAATCGGGGGCTCCCTTTAGGGTTCCGATTTAGTGCTTTACGGCAC 
               
               
                   
               
               
                 CTCGACCCCAAAAAACTTGATTAGGGTGATGGTTCACGTAGTGGGCCATC 
               
               
                   
               
               
                 GCCCTGATAGACGGTTTTTCGCCCTTTGACGTTGGAGTCCACGTTCTTTA 
               
               
                   
               
               
                 ATAGTGGACTCTTGTTCCAAACTGGAACAACACTCAACCCTATCTCGGTC 
               
               
                   
               
               
                 TATTCTTTTGATTTATAAGGGATTTTGCCGATTTCGGCCTATTGGTTAAA 
               
               
                   
               
               
                 AAATGAGCTGATTTAACAAAAATTTAACGCGAATTTTAACAAAATATTAA 
               
               
                   
               
               
                 CGTTTACAATTTCCCATTCGCCATTCAGGCTGCGCAACTGTTGGGAAGGG 
               
               
                   
               
               
                 CGATCGGTGCGGGCCTCTTCGCTATTACGCCA 
               
            
           
         
       
     
     Certain compounds of the disclosure were evaluated in HAQ STING in vitro binding assay as described above. The following table tabulates the biological data for these compounds as EC 50  values. 
     
       
         
           
               
             
               
                 TABLE 12 
               
             
            
               
                   
               
               
                   3 H-cGAMP filtration binding assay for HAQ STING 
               
            
           
           
               
               
               
               
               
               
            
               
                 Compound 
                 EC 50  (nM) 
                 Compound 
                 EC 50  (nM) 
                 Compound 
                 EC 50  (nM) 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Example 1 
                 &lt;1 
                 Example 55 
                 55.3 
                 Example 134 
                 &lt;1 
               
               
                 Example 2 
                 1.3 
                 Example 56 
                 89.4 
                 Example 135 
                 253.4 
               
               
                 Example 3 
                 257.1 
                 Example 57 
                 437.9 
                 Example 136 
                 3.7 
               
               
                 Example 4 
                 22 
                 Example 58 
                 3.1 
                 Example 137 
                 11.4 
               
               
                 Example 5 
                 1.1 
                 Example 59 
                 11.8 
                 Example 138 
                 738.8 
               
               
                 Example 6 
                 &lt;1 
                 Example 60 
                 42.5 
                 Example 139 
                 &lt;1 
               
               
                 Example 7 
                 1.2 
                 Example 61 
                 18.2 
                 Example 140 
                 12.9 
               
               
                 Example 8 
                 13.6 
                 Example 66 
                 117.1 
                 Example 141 
                 &lt;1 
               
               
                 Example 9 
                 7.2 
                 Example 67 
                 6.4 
                 Example 142 
                 6.2 
               
               
                 Example 10 
                 4.9 
                 Example 68 
                 63.8 
                 Example 143 
                 1.05 
               
               
                 Example 11 
                 1.2 
                 Example 69 
                 &lt;1 
                 Example 144 
                 &lt;1 
               
               
                 Example 12 
                 &lt;1 
                 Example 70 
                 2 
                 Example 145 
                 &lt;1 
               
               
                 Example 13 
                 1.5 
                 Example 71 
                 &lt;1 
                 Example 146 
                 5.6 
               
               
                 Example 14 
                 &lt;1 
                 Example 72 
                 &lt;1 
                 Example 147 
                 1.4 
               
               
                 Example 15 
                 378.1 
                 Example 73 
                 834 
                 Example 148 
                 33.3 
               
               
                 Example 16 
                 12.4 
                 Example 74 
                 5.8 
                 Example 149 
                 8.4 
               
               
                 Example 17 
                 121 
                 Example 75 
                 2.6 
                 Example 150 
                 &lt;1 
               
               
                 Example 18 
                 53.9 
                 Example 76 
                 75.4 
                 Example 151 
                 &lt;1 
               
               
                 Example 19 
                 173 
                 Example 77 
                 160.5 
                 Example 152 
                 &lt;1 
               
               
                 Example 20 
                 &lt;1 
                 Example 78 
                 14.6 
                 Example 244 
                 156.6 
               
               
                 Example 21 
                 1.3 
                 Example 79 
                 103.2 
                 Example 245 
                 2.7 
               
               
                 Example 22 
                 4822 
                 Example 80 
                 1.3 
                 Example 246 
                 21.3 
               
               
                 Example 23 
                 &lt;1 
                 Example 81 
                 &lt;1 
                 Example 247 
                 &lt;1 
               
               
                 Example 24 
                 2.4 
                 Example 82 
                 21.5 
                 Example 290 
                 2.5 
               
               
                 Example 25 
                 3.4 
                 Example 83 
                 3.7 
                 Example 291 
                 64.7 
               
               
                 Example 26 
                 &lt;1 
                 Example 85 
                 &lt;1 
                 Example 292 
                 2.6 
               
               
                 Example 27 
                 1.3 
                 Example 86 
                 &lt;1 
                 Example 293 
                 1.9 
               
               
                 Example 28 
                 18.7 
                 Example 87 
                 &lt;1 
                 Example 294 
                 6.6 
               
               
                 Example 30 
                 91 
                 Example 88 
                 &lt;1 
                 Example 295 
                 29.6 
               
               
                 Example 31 
                 94 
                 Example 89 
                 8272 
                 Example 296 
                 4.1 
               
               
                 Example 32 
                 11.1 
                 Example 90 
                 1.7 
                 Example 297 
                 &lt;1 
               
               
                 Example 33 
                 11.9 
                 Example 91 
                 15.8 
                 Example 298 
                 52.9 
               
               
                 Example 34 
                 24.6 
                 Example 92 
                 114 
                 Example 299 
                 1325 
               
               
                 Example 35 
                 7.9 
                 Example 93 
                 &lt;1 
                 Example 300 
                 5.1 
               
               
                 Example 36 
                 21.5 
                 Example 94 
                 24.6 
                 Example 301 
                 4.8 
               
               
                 Example 37 
                 619.6 
                 Example 95 
                 13.9 
                 Example 302 
                 2.3 
               
               
                 Example 38 
                 3 
                 Example 96 
                 5.3 
                 Example 303 
                 &lt;1 
               
               
                 Example 69 
                 &lt;1 
                 Example 97 
                 &lt;1 
                 Example 304 
                 3.3 
               
               
                 Example 70 
                 2 
                 Example 98 
                 1.8 
                 Example 305 
                 326.2 
               
               
                 Example 71 
                 &lt;1 
                 Example 99 
                 &lt;1 
                 Example 306 
                 3.6 
               
               
                 Example 72 
                 &lt;1 
                 Example 100 
                 16.7 
                 Example 307 
                 &lt;1 
               
               
                 Example 73 
                 834 
                 Example 101 
                 8 
                 Example 308 
                 1.6 
               
               
                 Example 74 
                 5.8 
                 Example 102 
                 &lt;1 
                 Example 309 
                 4 
               
               
                 Example 39 
                 24.4 
                 Example 117 
                 1 
                 Example 310 
                 27.6 
               
               
                 Example 40 
                 3.2 
                 Example 118 
                 1.4 
                 Example 311 
                 1595 
               
               
                 Example 41 
                 11.8 
                 Example 119 
                 17.8 
                 Example 312 
                 122.5 
               
               
                 Example 42 
                 15.2 
                 Example 120 
                 45.1 
                 Example 313 
                 210.6 
               
               
                 Example 43 
                 162.2 
                 Example 121 
                 &lt;1 
                 Example 314 
                 &lt;1 
               
               
                 Example 44 
                 17.1 
                 Example 123 
                 5.1 
                 Example 315 
                 49.9 
               
               
                 Example 45 
                 24.8 
                 Example 124 
                 &lt;1 
                 Example 316 
                 2324 
               
               
                 Example 46 
                 11.7 
                 Example 125 
                 21.7 
                 Example 317 
                 &lt;1 
               
               
                 Example 47 
                 39.2 
                 Example 126 
                 9.7 
                 Example 318 
                 6.2 
               
               
                 Example 48 
                 1.2 
                 Example 127 
                 24.4 
                 Example 319 
                 7.3 
               
               
                 Example 49 
                 30 
                 Example 128 
                 &lt;1 
                 Example 320 
                 6.3 
               
               
                 Example 50 
                 2.7 
                 Example 129 
                 88.6 
                 Example 321 
                 112.2 
               
               
                 Example 51 
                 287.1 
                 Example 130 
                 &lt;1 
                 Example 322 
                 68.8 
               
               
                 Example 52 
                 1.5 
                 Example 131 
                 2.4 
                 Example 332 
                 8.2 
               
               
                 Example 53 
                 1.7 
                 Example 132 
                 25.9 
                 Example 333 
                 45.9 
               
               
                 Example 54 
                 &lt;1 
                 Example 133 
                 61.4 
               
               
                   
               
            
           
         
       
     
     Example 350:  3 H-cGAMP Filtration Binding Assay (WT STING) 
     The ability of compounds to bind STING is quantified by their ability to compete with tritiated cGAMP ligand for human STING receptor membrane using a radioactive filter-binding assay. The binding assay employs STING receptor obtained from  Trichoplusia ni  cell membranes ( T. ni ; Expression Systems, cat #94-002F, www.expressionsystems.com) overexpressing full-length WT STING prepared in-house and tritiated cGAMP ligand also purified in-house. 
     The basic WT STING filtration assay protocol is as follows: 
     16 nM of [ 3 H]c-GAMP ligand was prepared by diluting into assay buffer, and 50 uL of this working stock was manually added to each well of the assay plate. After ligand addition, 2 uL of either titrated test compound, DMSO control (Sigma #276855), or cold cGAMP control (prepared in-house) was added to the appropriate wells using a Biomek FX. The serially titrated compound was prepared on a Hamilton STARPlus CORE in a 96-well plate (Greiner, #651201) using a 1:3 ten-point dose response format. Following compound addition, a 2.2 ug/ml working concentration of STING membrane (SEQ. ID. No. 4) was prepared by diluting concentrated membrane into assay buffer (lx PBS; Invitrogen # SH30028.02) and douncing 7× using a manual tissue homogenizer (Wheaton, #357546). 148 uL of this prepared membrane was then manually added to each well of a 96-well deep-well polypropylene plate (Fisher Scientific, #12-566-121). Compound, ligand, and membrane then incubated for 60 min at RT before the contents of each assay plate were filtered through a 96-well GF/B filter plate (PerkinElmer, #6005250) using a TomTec MachIII Cell Harvester equipped with 20 mM HEPES buffer (Fisher Scientific, # BP299500). The filter plates were then dried at 55° C. for 30 min using a pressurized VWR oven before 30 uL of Ultima GoldF scintillate was added to each well. Tritium levels for each reaction well were then measured using a PerkinElmer TopCount plate reader. 
     After normalization to controls, the percent activity for each compound concentration was calculated by measuring the amount of remaining radioactivity. The plot of percent activity versus the log of compound concentration was fit with a 4-parameter dose response equation to calculate EC 50  values. 
     The final reaction conditions were: 
     
       
         
           
               
               
               
             
               
                   
               
               
                 Component 
                 Volume (uL) 
                 Final Concentration 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 STING membrane 
                 148 
                 1.5 
                 ug/ml 
               
               
                   3 H-cGAMP 
                 50 
                 4.0 
                 nM 
               
               
                 Low Control (cold cGAMP) 
                 2 
                 10 
                 uM 
               
               
                 Test compound/DMSO 
                 2 
                 10 
                 uM 
               
               
                   
               
            
           
         
       
     
     Compound concentrations tested were 20.000, 637.00, 2.200, 0.740, 0.247, 0.082, 0.027, 0.009, 0.003, and 0.001 μM with 1.0% residual DMSO. 
     Full-Length STING (WT) Virus Generation 
     STING virus was generated using an insect cell baculovirus system.  Spodoptera frugiperda  Sf21 cells (Kempbio, Inc.) were diluted to 5e5 cells/ml in Sf-900II SFM media (LifeTechnologies #10902088) without antibiotics. The cell suspension was added to each well of a treated 6-well plate (2 mL per well, 1e6 cells total), and the cells were allowed to adhere for at least 30 min. Meanwhile, a 1 mL co-transfection mix was assembled by combining 500 ng of WT STING[STING(1-379)H232R-gg-AviTag-gs-HRV3C-HIS8/pBAC1] (Genewiz custom synthesis) with 1 mL Sf-900II SFM media containing 10 μL Cellfectin® II Reagent (Invitrogen #10362100) and 100 ng viral backbone BestBac 2.0, v-cath/chiA Deleted Linearized Baculovirus DNA (Expression Systems #91-002). The transfection mixtures were allowed to incubate for 30 min. After incubation, media was gently removed from the adhered cells in the 6-well plate, the 1 mL transfection mixtures were added (1 mL per well), and the plate was placed in a humidified incubator at 27° C. The following day, 1 mL Sf-900II SFM media (no antibiotics) was added to each well of the 6-well plate. After media addition, the cells were allowed to incubate with DNA [(SEQ. ID. No. 5) and linearized viral backbone BestBac 2.0] at 27° C. for 5-7 days to generate the P0 viral stock. To generate P1 viral stocks, 0.5 mL of P0 viral supernatant was added to 50 mL uninfected Sf21 cells (seeded the day prior to infection at a density of 5×10 5  cells/mL to allow for one overnight doubling) in Sf-900II SFM media containing 5 g/mL gentamicin (Invitrogen #15710072). The infected cells were then incubated at 27° C. for 3d while shaking at 110 rpm (ATR Biotech Multitron Infors HT # AJ118). On day 3, P1 cultures were counted using a ViCell XR (Beckman Coulter Life Sciences #383556) to confirm infection had occurred (cell size ≥3 μm larger than uninfected cells and viability approximately 85-95%). Cultures were harvested in 50 mL conical tubes and centrifuged at 2000×g for 10 min at 4° C. The P1 viral supernatants were poured off into clean 50 ml centrifuge tubes, and the remaining P1 cell pellets were used to generate Baculovirus Infected Insect Cells (BIICs) according to in-house validated SOP. Cryopreservation media containing Sf-900II SFM media with 10% heat inactivated FBS, 10% DMSO (Sigma # D2650), and 5 μg/ml gentamicin was prepared in-house and sterilized through 0.22 μM filter immediately prior to use. P1 cell pellets were resuspended to a density of 2e7 cells/ml and aliquoted into cryovials (1 mL per vial). Cryovials were placed in Mr. Frosty cell freezers O/N at −80° C. and transferred to liquid nitrogen for long term storage the following day. To generate P2 viral stock, 0.5 mL of the P1 viral supernatant was added to 50 mL uninfected Sf21 cells (seeded the day prior to infection at a density of 5×10 5  cells/mL to allow for one overnight doubling) in Sf-900II SFM media containing 5 μg/mL gentamicin. These cells were incubated at 27° C. for 3d while shaking at 110 rpm before harvesting P2 stock with centrifugation at 2000×g for 10 min at 4° C. The P2 viral supernatants were poured off and discarded, while the P2 cell pellets were used to generate P2 BIICs following the same protocol described above. The baculovirus generation protocol has been validated to consistently produce P1/P2 BIICs with titers of 2e9 pfu/mL (2e7 cells/mL×100 pfu/cell). 
     Full-Length STING (WT) Expression 
     To generate STING membranes, P1/P2 BIICs were amplified overnight by adding thawed BIICs to Sf21 cells seeded at a density of 1.0×10 6  cells/mL. The volume of BIIC used to infect the culture was calculated using an assumed BIIC titer of 2e9 pfu/ml to achieve an MOI of 10 in the overnight amplification. After culturing overnight, the cells were counted on a ViCell XR to confirm infection had occurred (cell size ≥3 μm larger than uninfected cells and viability approximately 80-90%). The volume of infected Sf21 cells from the overnight amplification used to infect the large-scale expression of  Trichoplusia ni  ( T. ni ; Expression Systems, cat #94-002F, www.expressionsystems.com) seeded at a density of 1.0×10 6  in cell media (ESF921 SFM containing 5 μg/mL gentamicin) at MOI=2.0 was calculated based on (100 pfu/infected Sf21 cell). The cells were allowed to express for 48 h at 27° C. before harvesting the cell pellet, by centrifugation at 3,400×g for 10 min at 4° C.  T. ni  cells were counted on a ViCell XR to confirm infection had occurred (cell size ≥3 μm larger than uninfected cells and viability approximately 80-90%) prior to harvest. 
     Full-Length STING (WT) Membrane Generation 
     Buffer stock reagents: 
     
         
         
           
             1) 1 M HEPES pH 7.5, Teknova, Cat # H1035 
             2) 5 M NaCl, Sigma Aldrich, Cat # S5150-1 L 
             3) KCl, Sigma Aldrich, Cat #319309-500ML 
             4) Complete EDTA-free protease inhibitor tablets, Roche Diagnostics, Cat #11873580001 
             5) Benzonase, Universal Nuclease, Pierce, Cat #88702 
           
         
       
    
     Lysis buffer [25 mM HEPES pH 7.5, 10 mM MgCl 2 , 20 mM KCl, (Benzonase 1:5000, Complete Protease Inhibitor tab/50 mL)] was added to the pellet of cells expressing full-length STING (WT) prepared above at 5 mL Lysis buffer/g of cell pellet. The pellet was resuspended and dounced twenty times using a Wheaton Dounce Homogenizer to disrupt the cell membrane. Homogenized lysate was then passed through the emulsiflex-C5 microfluidizer at a pressure close to 5000 PSI. The resuspended pellet was centrifuged at 36,000 rpm (100,000×g) in a 45Ti rotor in the ultra-high speed centrifuge for 45 min, 4° C. The supernatant was removed. The pellet then was resuspended in wash buffer [(25 mM HEPES pH 7.5, 1 mM MgCl 2 , 20 mM KCl, 1M NaCl (Complete Protease Inhibitor tab/50 mL)] at a volume of 50 mL/pellet/centrifuge tube. The pellet/Wash buffer mixture was then homogenized, using a glass homogenizer on ice (20 strokes), followed by centrifugation at 36,000 rpm for 45 min at 4° C. The supernatant was removed. The wash step was repeated once more. The resulting membrane was resuspended in 20 mM HEPES pH 7.5, 500 mM NaCl, 10% glycerol, EDTA-free Protease Inhibitors (1 tablet/50 mL). The protein concentration was measured by Bradford assay (Bio-Rad Protein Assay, Cat #500-0006), and protein enrichment was determined by SDS-PAGE and confirmed by Western blot. The resuspended membranes were stored at −80° C. 
     Full-Length STING WT [STING(1-379)H232R-gg-AviTag-gs-HRV3C-HIS8] Amino Acid Sequence: 
                    (SEQ. ID. No. 4)       MPHSSLHPSIPCPRGHGAQKAALVLLSACLVTLWGLGEPPEHTLRYLVLH               LASLQLGLLLNGVCSLAEELRHIHSRYRGSYWRTVRACLGCPLRRGALLL               LSIYFYYSLPNAVGPPFTWMLALLGLSQALNILLGLKGLAPAEISAVCEK               GNFNVAHGLAWSYYIGYLRLILPELQARIRTYNQHYNNLLRGAVSQRLYI               LLPLDCGVPDNLSMADPNIRFLDKLPQQTGDRAGIKDRVYSNSIYELLEN               GQRAGTCVLEYATPLQTLFAMSQYSQAGFSREDRLEQAKLFCRTLEDILA               DAPESQNNCRLIAYQEPADDSSFSLSQEVLRHLRQEEKEEVTVGSLKTSA               VPSTSTMSQEPELLISGMEKPLPLRTDFSGGGLNDIFEAQKIEWHEGSLE               VLFQGHHHHHHHH            
Full-Length WT STING [STING(1-379)H232R-gg-AviTag-gs-HRV3C-HIS8/pBAC1] Plasmid Sequence:
 
     
       
         
           
               
            
               
                 (SEQ. ID. No. 5) 
               
               
                 GGAACGGCTCCGCCCACTATTAATGAAATTAAAAATTCCAATTTTAAAAA 
               
               
                   
               
               
                 ACGCAGCAAGAGAAACATTTGTATGAAAGAATGCGTAGAAGGAAAGAAAA 
               
               
                   
               
               
                 ATGTCGTCGACATGCTGAACAACAAGATTAATATGCCTCCGTGTATAAAA 
               
               
                   
               
               
                 AAAATATTGAACGATTTGAAAGAAAACAATGTACCGCGCGGCGGTATGTA 
               
               
                   
               
               
                 CAGGAAGAGGTTTATACTAAACTGTTACATTGCAAACGTGGTTTCGTGTG 
               
               
                   
               
               
                 CCAAGTGTGAAAACCGATGTTTAATCAAGGCTCTGACGCATTTCTACAAC 
               
               
                   
               
               
                 CACGACTCCAAGTGTGTGGGTGAAGTCATGCATCTTTTAATCAAATCCCA 
               
               
                   
               
               
                 AGATGTGTATAAACCACCAAACTGCCAAAAAATGAAAACTGTCGACAAGC 
               
               
                   
               
               
                 TCTGTCCGTTTGCTGGCAACTGCAAGGGTCTCAATCCTATTTGTAATTAT 
               
               
                   
               
               
                 TGAATAATAAAACAATTATAAATGTCAAATTTGTTTTTTATTAACGATAC 
               
               
                   
               
               
                 AAACCAAACGCAACAAGAACATTTGTAGTATTATCTATAATTGAAAACGC 
               
               
                   
               
               
                 GTAGTTATAATCGCTGAGGTAATATTTAAAATCATTTTCAAATGATTCAC 
               
               
                   
               
               
                 AGTTAATTTGCGACAATATAATTTTATTTTCACATAAACTAGACGCCTTG 
               
               
                   
               
               
                 TCGTCTTCTTCTTCGTATTCCTTCTCTTTTTCATTTTTCTCTTCATAAAA 
               
               
                   
               
               
                 ATTAACATAGTTATTATCGTATCCATATATGTATCTATCGTATAGAGTAA 
               
               
                   
               
               
                 ATTTTTTGTTGTCATAAATATATATGTCTTTTTTAATGGGGTGTATAGTA 
               
               
                   
               
               
                 CCGCTGCGCATAGTTTTTCTGTAATTTACAACAGTGCTATTTTCTGGTAG 
               
               
                   
               
               
                 TTCTTCGGAGTGTGTTGCTTTAATTATTAAATTTATATAATCAATGAATT 
               
               
                   
               
               
                 TGGGATCGTCGGTTTTGTACAATATGTTGCCGGCATAGTACGCAGCTTCT 
               
               
                   
               
               
                 TCTAGTTCAATTACACCATTTTTTAGCAGCACCGGATTAACATAACTTTC 
               
               
                   
               
               
                 CAAAATGTTGTACGAACCGTTAAACAAAAACAGTTCACCTCCCTTTTCTA 
               
               
                   
               
               
                 TACTATTGTCTGCGAGCAGTTGTTTGTTGTTAAAAATAACAGCCATTGTA 
               
               
                   
               
               
                 ATGAGACGCACAAACTAATATCACAAACTGGAAATGTCTATCAATATATA 
               
               
                   
               
               
                 GTTGCTGATCAGATCTGATCATGGAGATAATTAAAATGATAACCATCTCG 
               
               
                   
               
               
                 CAAATAAATAAGTATTTTACTGTTTTCGTAACAGTTTTGTAATAAAAAAA 
               
               
                   
               
               
                 CCTATAAATATAGGATCCATGCCCCACTCCAGCCTGCATCCATCCATCCC 
               
               
                   
               
               
                 GTGTCCCAGGGGTCACGGGGCCCAGAAGGCAGCCTTGGTTCTGCTGAGTG 
               
               
                   
               
               
                 CCTGCCTGGTGACCCTTTGGGGGCTAGGAGAGCCACCAGAGCACACTCTC 
               
               
                   
               
               
                 CGGTACCTGGTGCTCCACCTAGCCTCCCTGCAGCTGGGACTGCTGTTAAA 
               
               
                   
               
               
                 CGGGGTCTGCAGCCTGGCTGAGGAGCTGCGCCACATCCACTCCAGGTACC 
               
               
                   
               
               
                 GGGGCAGCTACTGGAGGACTGTGCGGGCCTGCCTGGGCTGCCCCCTCCGC 
               
               
                   
               
               
                 CGTGGGGCCCTGTTGCTGCTGTCCATCTATTTCTACTACTCCCTCCCAAA 
               
               
                   
               
               
                 TGCGGTCGGCCCGCCCTTCACTTGGATGCTTGCCCTCCTGGGCCTCTCGC 
               
               
                   
               
               
                 AGGCACTGAACATCCTCCTGGGCCTCAAGGGCCTGGCCCCAGCTGAGATC 
               
               
                   
               
               
                 TCTGCAGTGTGTGAAAAAGGGAATTTCAACGTGGCCCATGGGCTGGCATG 
               
               
                   
               
               
                 GTCATATTACATCGGATATCTGCGGCTGATCCTGCCAGAGCTCCAGGCCC 
               
               
                   
               
               
                 GGATTCGAACTTACAATCAGCATTACAACAACCTGCTACGGGGTGCAGTG 
               
               
                   
               
               
                 AGCCAGCGGCTGTATATTCTCCTCCCATTGGACTGTGGGGTGCCTGATAA 
               
               
                   
               
               
                 CCTGAGTATGGCTGACCCCAACATTCGCTTCCTGGATAAACTGCCCCAGC 
               
               
                   
               
               
                 AGACCGGTGACCGTGCTGGCATCAAGGATCGGGTTTACAGCAACAGCATC 
               
               
                   
               
               
                 TATGAGCTTCTGGAGAACGGGCAGCGGGCGGGCACCTGTGTCCTGGAGTA 
               
               
                   
               
               
                 CGCCACCCCCTTGCAGACTTTGTTTGCCATGTCACAATACAGTCAAGCTG 
               
               
                   
               
               
                 GCTTTAGCCGGGAGGATAGGCTTGAGCAGGCCAAACTCTTCTGCCGGACA 
               
               
                   
               
               
                 CTTGAGGACATCCTGGCAGATGCCCCTGAGTCTCAGAACAACTGCCGCCT 
               
               
                   
               
               
                 CATTGCCTACCAGGAACCTGCAGATGACAGCAGCTTCTCGCTGTCCCAGG 
               
               
                   
               
               
                 AGGTTCTCCGGCACCTGCGGCAGGAGGAAAAGGAAGAGGTTACTGTGGGC 
               
               
                   
               
               
                 AGCTTGAAGACCTCAGCGGTGCCCAGTACCTCCACGATGTCCCAAGAGCC 
               
               
                   
               
               
                 TGAGCTCCTCATCAGTGGAATGGAAAAGCCCCTCCCTCTCCGCACGGATT 
               
               
                   
               
               
                 TCTCTGGCGGTGGCCTGAACGACATCTTCGAAGCCCAGAAAATCGAATGG 
               
               
                   
               
               
                 CATGAAGGCAGCCTGGAAGTGCTGTTCCAGGGCCCACACCACCATCATCA 
               
               
                   
               
               
                 CCATCACCATTAATGAGCGGCCGCACTCGAGCACCACCACCACCACCACT 
               
               
                   
               
               
                 AACCTAGGTAGCTGAGCGCATGCAAGCTGATCCGGGTTATTAGTACATTT 
               
               
                   
               
               
                 ATTAAGCGCTAGATTCTGTGCGTTGTTGATTTACAGACAATTGTTGTACG 
               
               
                   
               
               
                 TATTTTAATAATTCATTAAATTTATAATCTTTAGGGTGGTATGTTAGAGC 
               
               
                   
               
               
                 GAAAATCAAATGATTTTCAGCGTCTTTATATCTGAATTTAAATATTAAAT 
               
               
                   
               
               
                 CCTCAATAGATTTGTAAAATAGGTTTCGATTAGTTTCAAACAAGGGTTGT 
               
               
                   
               
               
                 TTTTCCGAACCGATGGCTGGACTATCTAATGGATTTTCGCTCAACGCCAC 
               
               
                   
               
               
                 AAAACTTGCCAAATCTTGTAGCAGCAATCTAGCTTTGTCGATATTCGTTT 
               
               
                   
               
               
                 GTGTTTTGTTTTGTAATAAAGGTTCGACGTCGTTCAAAATATTATGCGCT 
               
               
                   
               
               
                 TTTGTATTTCTTTCATCACTGTCGTTAGTGTACAATTGACTCGACGTAAA 
               
               
                   
               
               
                 CACGTTAAATAGAGCTTGGACATATTTAACATCGGGCGTGTTAGCTTTAT 
               
               
                   
               
               
                 TAGGCCGATTATCGTCGTCGTCCCAACCCTCGTCGTTAGAAGTTGCTTCC 
               
               
                   
               
               
                 GAAGACGATTTTGCCATAGCCACACGACGCCTATTAATTGTGTCGGCTAA 
               
               
                   
               
               
                 CACGTCCGCGATCAAATTTGTAGTTGAGCTTTTTGGAATTATTTCTGATT 
               
               
                   
               
               
                 GCGGGCGTTTTTGGGCGGGTTTCAATCTAACTGTGCCCGATTTTAATTCA 
               
               
                   
               
               
                 GACAACACGTTAGAAAGCGATGGTGCAGGCGGTGGTAACATTTCAGACGG 
               
               
                   
               
               
                 CAAATCTACTAATGGCGGCGGTGGTGGAGCTGATGATAAATCTACCATCG 
               
               
                   
               
               
                 GTGGAGGCGCAGGCGGGGCTGGCGGCGGAGGCGGAGGCGGAGGTGGTGGC 
               
               
                   
               
               
                 GGTGATGCAGACGGCGGTTTAGGCTCAAATGTCTCTTTAGGCAACACAGT 
               
               
                   
               
               
                 CGGCACCTCAACTATTGTACTGGTTTCGGGCGCCGTTTTTGGTTTGACCG 
               
               
                   
               
               
                 GTCTGAGACGAGTGCGATTTTTTTCGTTTCTAATAGCTTCCAACAATTGT 
               
               
                   
               
               
                 TGTCTGTCGTCTAAAGGTGCAGCGGGTTGAGGTTCCGTCGGCATTGGTGG 
               
               
                   
               
               
                 AGCGGGCGGCAATTCAGACATCGATGGTGGTGGTGGTGGTGGAGGCGCTG 
               
               
                   
               
               
                 GAATGTTAGGCACGGGAGAAGGTGGTGGCGGCGGTGCCGCCGGTATAATT 
               
               
                   
               
               
                 TGTTCTGGTTTAGTTTGTTCGCGCACGATTGTGGGCACCGGCGCAGGCGC 
               
               
                   
               
               
                 CGCTGGCTGCACAACGGAAGGTCGTCTGCTTCGAGGCAGCGCTTGGGGTG 
               
               
                   
               
               
                 GTGGCAATTCAATATTATAATTGGAATACAAATCGTAAAAATCTGCTATA 
               
               
                   
               
               
                 AGCATTGTAATTTCGCTATCGTTTACCGTGCCGATATTTAACAACCGCTC 
               
               
                   
               
               
                 AATGTAAGCAATTGTATTGTAAAGAGATTGTCTCAAGCTCGGATCGATCC 
               
               
                   
               
               
                 CGCACGCCGATAACAAGCCTTTTCATTTTTACTACAGCATTGTAGTGGCG 
               
               
                   
               
               
                 AGACACTTCGCTGTCGTCGAGGTTTAAACGCTTCCTCGCTCACTGACTCG 
               
               
                   
               
               
                 CTGCGCTCGGTCGTTCGGCTGCGGCGAGCGGTATCAGCTCACTCAAAGGC 
               
               
                   
               
               
                 GGTAATACGGTTATCCACAGAATCAGGGGATAACGCAGGAAAGAACATGT 
               
               
                   
               
               
                 GAGCAAAAGGCCAGCAAAAGGCCAGGAACCGTAAAAAGGCCGCGTTGCTG 
               
               
                   
               
               
                 GCGTTTTTCCATAGGCTCCGCCCCCCTGACGAGCATCACAAAAATCGACG 
               
               
                   
               
               
                 CTCAAGTCAGAGGTGGCGAAACCCGACAGGACTATAAAGATACCAGGCGT 
               
               
                   
               
               
                 TTCCCCCTGGAAGCTCCCTCGTGCGCTCTCCTGTTCCGACCCTGCCGCTT 
               
               
                   
               
               
                 ACCGGATACCTGTCCGCCTTTCTCCCTTCGGGAAGCGTGGCGCTTTCTCA 
               
               
                   
               
               
                 TAGCTCACGCTGTAGGTATCTCAGTTCGGTGTAGGTCGTTCGCTCCAAGC 
               
               
                   
               
               
                 TGGGCTGTGTGCACGAACCCCCCGTTCAGCCCGACCGCTGCGCCTTATCC 
               
               
                   
               
               
                 GGTAACTATCGTCTTGAGTCCAACCCGGTAAGACACGACTTATCGCCACT 
               
               
                   
               
               
                 GGCAGCAGCCACTGGTAACAGGATTAGCAGAGCGAGGTATGTAGGCGGTG 
               
               
                   
               
               
                 CTACAGAGTTCTTGAAGTGGTGGCCTAACTACGGCTACACTAGAAGGACA 
               
               
                   
               
               
                 GTATTTGGTATCTGCGCTCTGCTGAAGCCAGTTACCTTCGGAAAAAGAGT 
               
               
                   
               
               
                 TGGTAGCTCTTGATCCGGCAAACAAACCACCGCTGGTAGCGGTGGTTTTT 
               
               
                   
               
               
                 TTGTTTGCAAGCAGCAGATTACGCGCAGAAAAAAAGGATCTCAAGAAGAT 
               
               
                   
               
               
                 CCTTTGATCTTTTCTACGGGGTCTGACGCTCAGTGGAACGAAAACTCACG 
               
               
                   
               
               
                 TTAAGGGATTTTGGTCATGAGATTATCAAAAAGGATCTTCACCTAGATCC 
               
               
                   
               
               
                 TTTTAAATTAAAAATGAAGTTTTAAATCAATCTAAAGTATATATGAGTAA 
               
               
                   
               
               
                 ACTTGGTCTGACAGTTACCAATGCTTAATCAGTGAGGCACCTATCTCAGC 
               
               
                   
               
               
                 GATCTGTCTATTTCGTTCATCCATAGTTGCCTGACTCCCCGTCGTGTAGA 
               
               
                   
               
               
                 TAACTACGATACGGGAGGGCTTACCATCTGGCCCCAGTGCTGCAATGATA 
               
               
                   
               
               
                 CCGCGAGACCCACGCTCACCGGCTCCAGATTTATCAGCAATAAACCAGCC 
               
               
                   
               
               
                 AGCCGGAAGGGCCGAGCGCAGAAGTGGTCCTGCAACTTTATCCGCCTCCA 
               
               
                   
               
               
                 TCCAGTCTATTAATTGTTGCCGGGAAGCTAGAGTAAGTAGTTCGCCAGTT 
               
               
                   
               
               
                 AATAGTTTGCGCAACGTTGTTGCCATTGCTACAGGCATCGTGGTGTCACG 
               
               
                   
               
               
                 CTCGTCGTTTGGTATGGCTTCATTCAGCTCCGGTTCCCAACGATCAAGGC 
               
               
                   
               
               
                 GAGTTACATGATCCCCCATGTTGTGCAAAAAAGCGGTTAGCTCCTTCGGT 
               
               
                   
               
               
                 CCTCCGATCGTTGTCAGAAGTAAGTTGGCCGCAGTGTTATCACTCATGGT 
               
               
                   
               
               
                 TATGGCAGCACTGCATAATTCTCTTACTGTCATGCCATCCGTAAGATGCT 
               
               
                   
               
               
                 TTTCTGTGACTGGTGAGTACTCAACCAAGTCATTCTGAGAATAGTGTATG 
               
               
                   
               
               
                 CGGCGACCGAGTTGCTCTTGCCCGGCGTCAATACGGGATAATACCGCGCC 
               
               
                   
               
               
                 ACATAGCAGAACTTTAAAAGTGCTCATCATTGGAAAACGTTCTTCGGGGC 
               
               
                   
               
               
                 GAAAACTCTCAAGGATCTTACCGCTGTTGAGATCCAGTTCGATGTAACCC 
               
               
                   
               
               
                 ACTCGTGCACCCAACTGATCTTCAGCATCTTTTACTTTCACCAGCGTTTC 
               
               
                   
               
               
                 TGGGTGAGCAAAAACAGGAAGGCAAAATGCCGCAAAAAAGGGAATAAGGG 
               
               
                   
               
               
                 CGACACGGAAATGTTGAATACTCATACTCTTCCTTTTTCAATATTATTGA 
               
               
                   
               
               
                 AGCATTTATCAGGGTTATTGTCTCATGAGCGGATACATATTTGAATGTAT 
               
               
                   
               
               
                 TTAGAAAAATAAACAAATAGGGGTTCCGCGCACATTTCCCCGAAAAGTGC 
               
               
                   
               
               
                 CACCTGACGCGCCCTGTAGCGGCGCATTAAGCGCGGCGGGTGTGGTGGTT 
               
               
                   
               
               
                 ACGCGCAGCGTGACCGCTACACTTGCCAGCGCCCTAGCGCCCGCTCCTTT 
               
               
                   
               
               
                 CGCTTTCTTCCCTTCCTTTCTCGCCACGTTCGCCGGCTTTCCCCGTCAAG 
               
               
                   
               
               
                 CTCTAAATCGGGGGCTCCCTTTAGGGTTCCGATTTAGTGCTTTACGGCAC 
               
               
                   
               
               
                 CTCGACCCCAAAAAACTTGATTAGGGTGATGGTTCACGTAGTGGGCCATC 
               
               
                   
               
               
                 GCCCTGATAGACGGTTTTTCGCCCTTTGACGTTGGAGTCCACGTTCTTTA 
               
               
                   
               
               
                 ATAGTGGACTCTTGTTCCAAACTGGAACAACACTCAACCCTATCTCGGTC 
               
               
                   
               
               
                 TATTCTTTTGATTTATAAGGGATTTTGCCGATTTCGGCCTATTGGTTAAA 
               
               
                   
               
               
                 AAATGAGCTGATTTAACAAAAATTTAACGCGAATTTTAACAAAATATTAA 
               
               
                   
               
               
                 CGTTTACAATTTCCCATTCGCCATTCAGGCTGCGCAACTGTTGGGAAGGG 
               
               
                   
               
               
                 CGATCGGTGCGGGCCTCTTCGCTATTACGCCA 
               
            
           
         
       
     
     Certain compounds of the disclosure were evaluated in WT STING in vitro binding assay as described above. The following table tabulates the biological data for these compounds as EC 50  values. 
     
       
         
           
               
             
               
                 TABLE 13 
               
             
            
               
                   
               
               
                   3 H-cGAMP filtration binding assay for WT STING 
               
            
           
           
               
               
               
               
               
               
            
               
                 Compound 
                 EC 50  (nM) 
                 Compound 
                 EC 50  (nM) 
                 Compound 
                 EC 50  (nM) 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Example 1 
                 3.5 
                 Example 139 
                 1.2 
                 Example 226 
                 27.8 
               
               
                 Example 2 
                 0.7 
                 Example 141 
                 &lt;1 
                 Example 227 
                 260.6 
               
               
                 Example 3 
                 574.3 
                 Example 142 
                 174.8 
                 Example 228 
                 1005 
               
               
                 Example 4 
                 43.5 
                 Example 144 
                 4.6 
                 Example 229 
                 31% Inh 
               
               
                   
                   
                   
                   
                   
                 @ 20 uM 
               
               
                 Example 5 
                 1.5 
                 Example 145 
                 14 
                 Example 230 
                 382.4 
               
               
                 Example 6 
                 2.9 
                 Example 148 
                 1932 
                 Example 231 
                 540.4 
               
               
                 Example 7 
                 &lt;1 
                 Example 149 
                 110.8 
                 Example 232 
                 3283 
               
               
                 Example 8 
                 81.4 
                 Example 152 
                 5.7 
                 Example 233 
                 33.8 
               
               
                 Example 9 
                 12.4 
                 Example 153 
                 6.5 
                 Example 234 
                 275.2 
               
               
                 Example 10 
                 23.2 
                 Example 154 
                 60 
                 Example 235 
                 14.9 
               
               
                 Example 13 
                 0.7 
                 Example 155 
                 &lt;1 
                 Example 236 
                 6963 
               
               
                 Example 14 
                 1.4 
                 Example 156 
                 &lt;1 
                 Example 237 
                 307.2 
               
               
                 Example 20 
                 1.4 
                 Example 157 
                 &lt;1 
                 Example 238 
                 66.3 
               
               
                 Example 21 
                 1.4 
                 Example 158 
                 40 
                 Example 239 
                 3.2 
               
               
                 Example 25 
                 16.1 
                 Example 159 
                 7.1 
                 Example 240 
                 73.6 
               
               
                 Example 26 
                 3.7 
                 Example 160 
                 10.3 
                 Example 241 
                 471.8 
               
               
                 Example 27 
                 10 
                 Example 161 
                 6.2 
                 Example 242 
                 1.1 
               
               
                 Example 28 
                 264.9 
                 Example 162 
                 100.7 
                 Example 243 
                 26.3 
               
               
                 Example 29 
                 5835 
                 Example 163 
                 14.3 
                 Example 247 
                 1.1 
               
               
                 Example 32 
                 25 
                 Example 164 
                 312.4 
                 Example 248 
                 31.7 
               
               
                 Example 38 
                 24.9 
                 Example 165 
                 2.9 
                 Example 249 
                 &lt;1 
               
               
                 Example 41 
                 505.9 
                 Example 166 
                 463.2 
                 Example 250 
                 17.3 
               
               
                 Example 42 
                 219 
                 Example 167 
                 87.7 
                 Example 251 
                 &lt;1 
               
               
                 Example 43 
                 1015 
                 Example 168 
                 8.6 
                 Example 252 
                 768.4 
               
               
                 Example 44 
                 1363 
                 Example 169 
                 186.6 
                 Example 253 
                 54.5 
               
               
                 Example 45 
                 104.8 
                 Example 170 
                 25.5 
                 Example 254 
                 39.7 
               
               
                 Example 46 
                 337 
                 Example 171 
                 18.7 
                 Example 255 
                 301.9 
               
               
                 Example 47 
                 444.1 
                 Example 172 
                 105.9 
                 Example 256 
                 93.5 
               
               
                 Example 51 
                 995.8 
                 Example 176 
                 16.2 
                 Example 257 
                 135.9 
               
               
                 Example 61 
                 378.7 
                 Example 177 
                 7.9 
                 Example 258 
                 5 
               
               
                 Example 62 
                 2.6 
                 Example 178 
                 37.4 
                 Example 259 
                 1.5 
               
               
                 Example 63 
                 68.8 
                 Example 179 
                 111.7 
                 Example 260 
                 7.2 
               
               
                 Example 64 
                 61.6 
                 Example 180 
                 832.1 
                 Example 261 
                 21.8 
               
               
                 Example 65 
                 249.6 
                 Example 181 
                 459.2 
                 Example 262 
                 57.3 
               
               
                 Example 70 
                 19.4 
                 Example 182 
                 3276 
                 Example 263 
                 4.8 
               
               
                 Example 71 
                 4.4 
                 Example 183 
                 3180 
                 Example 264 
                 177.5 
               
               
                 Example 72 
                 &lt;1 
                 Example 184 
                 &lt;1 
                 Example 265 
                 5473 
               
               
                 Example 81 
                 3.1 
                 Example 185 
                 201.1 
                 Example 266 
                 1.9 
               
               
                 Example 82 
                 14.6 
                 Example 186 
                 30.2 
                 Example 267 
                 6267 
               
               
                 Example 84 
                 6.3 
                 Example 187 
                 6.5 
                 Example 268 
                 77 
               
               
                 Example 86 
                 2 
                 Example 188 
                 47.6 
                 Example 269 
                 4837 
               
               
                 Example 89 
                 &lt;1 
                 Example 189 
                 423.9 
                 Example 270 
                 4383 
               
               
                 Example 90 
                 4.4 
                 Example 190 
                 408.7 
                 Example 271 
                 12.8 
               
               
                 Example 93 
                 1.9 
                 Example 191 
                 281.2 
                 Example 272 
                 749.6 
               
               
                 Example 94 
                 523.8 
                 Example 192 
                 3867 
                 Example 273 
                 216.4 
               
               
                 Example 95 
                 64 
                 Example 193 
                 190.5 
                 Example 274 
                 2.3 
               
               
                 Example 96 
                 57.8 
                 Example 194 
                 159.2 
                 Example 275 
                 21.8 
               
               
                 Example 97 
                 0.4 
                 Example 195 
                 1855 
                 Example 276 
                 321.5 
               
               
                 Example 98 
                 151.7 
                 Example 196 
                 1033 
                 Example 277 
                 28.7 
               
               
                 Example 99 
                 1.8 
                 Example 197 
                 1.2 
                 Example 278 
                 477.9 
               
               
                 Example 100 
                 552 
                 Example 198 
                 19.1 
                 Example 279 
                 1235 
               
               
                 Example 101 
                 74.4 
                 Example 199 
                 72 
                 Example 280 
                 1186 
               
               
                 Example 84 
                 6.3 
                 Example 200 
                 15 
                 Example 281 
                 2485 
               
               
                 Example 86 
                 2 
                 Example 201 
                 649.5 
                 Example 282 
                 12190 
               
               
                 Example 102 
                 1 
                 Example 202 
                 813.5 
                 Example 283 
                 17.2 
               
               
                 Example 103 
                 &lt;1 
                 Example 203 
                 7.3 
                 Example 284 
                 128.3 
               
               
                 Example 104 
                 11.6 
                 Example 204 
                 1233 
                 Example 285 
                 277.1 
               
               
                 Example 105 
                 3.9 
                 Example 205 
                 42.7 
                 Example 286 
                 4010 
               
               
                 Example 106 
                 &lt;1 
                 Example 206 
                 259.7 
                 Example 287 
                 80.2 
               
               
                 Example 107 
                 17.9 
                 Example 207 
                 1.4 
                 Example 288 
                 24.9 
               
               
                 Example 108 
                 1784 
                 Example 208 
                 23.3 
                 Example 289 
                 5.3 
               
               
                 Example 109 
                 1393 
                 Example 209 
                 9.5 
                 Example 308 
                 3.3 
               
               
                 Example 110 
                 141.4 
                 Example 210 
                 28.5 
                 Example 323 
                 3.7 
               
               
                 Example 111 
                 155.1 
                 Example 211 
                 1045 
                 Example 324 
                 10.7 
               
               
                 Example 112 
                 1279 
                 Example 212 
                 11.8 
                 Example 325 
                 866.1 
               
               
                 Example 113 
                 44.2 
                 Example 213 
                 135 
                 Example 326 
                 89.7 
               
               
                 Example 114 
                 3.3 
                 Example 214 
                 2.1 
                 Example 327 
                 14 
               
               
                 Example 115 
                 67.9 
                 Example 215 
                 33.1 
                 Example 328 
                 74.4 
               
               
                 Example 116 
                 1624 
                 Example 216 
                 3.4 
                 Example 329 
                 31.7 
               
               
                 Example 117 
                 1.7 
                 Example 217 
                 66.2 
                 Example 330 
                 204 
               
               
                 Example 118 
                 1.6 
                 Example 218 
                 13.8 
                 Example 331 
                 182.9 
               
               
                 Example 119 
                 40 
                 Example 219 
                 530.5 
                 Example 334 
                 110.5 
               
               
                 Example 120 
                 393.7 
                 Example 220 
                 29% Inh 
                 Example 335 
                 5.2 
               
               
                   
                   
                   
                 @ 20 uM 
               
               
                 Example 122 
                 179.2 
                 Example 221 
                 &lt;1 
                 Example 336 
                 422.2 
               
               
                 Example 124 
                 4 
                 Example 222 
                 60 
                 Example 337 
                 29.2 
               
               
                 Example 126 
                 447.4 
                 Example 223 
                 302.5 
                 Example 338 
                 441.7 
               
               
                 Example 128 
                 19.5 
                 Example 224 
                 37.4 
               
               
                 Example 129 
                 973.3 
                 Example 225 
                 779.3 
               
               
                   
               
            
           
         
       
     
     Example 351: IFN-β Secretion in THP1 Cell Culture (5 h) 
     The ability of compounds to stimulate the secretion of interferon-beta from THP1 cells was measured using a human IFN-β AlphaLISA kit (Perkin Elmer, Cat. No. AL265F). The basic protocol is as follows: 
     A Labcyte Echo 550 acoustic dispenser was used to transfer 120 nL of compound dissolved in DMSO into the wells of an empty, sterile 384-well microplate, (Corning, Cat. No. 3712). THP1 cells (American Type Culture Collection, Cat. No. TIB202) previously frozen in Recovery Medium (Life Technologies, Cat. No. 12648-010) were thawed and immediately diluted 10-fold into 37° C. assay medium (RPMI 1640+L-Glutamine &amp; phenol red, Life Technologies, Cat. No. 11875-085; 0.5% heat inactivated fetal bovine serum, Sigma Aldrich, Cat. No. F4135; 1 mM Sodium Pyruvate, Life Technologies, Cat. No. 11360-070; lx non-essential amino acids; Life Technologies, Cat. No. 11140-050). The cell viability and count was ascertained using a Beckman Coulter V-Cell XR cell counter. The cells suspension was centrifuged at 200×g for 5 min at RT. Cells were resuspended to a density of 0.8×10 6 /mL in 37° C. assay medium. Subsequent liquid transfers were performed using either a Matrix electronic multichannel pipette or an Agilent Bravo Automated Liquid Handling Platform. 
     The assay was started by dispensing 40 μL of the previously prepared cell suspension into the wells of the plate containing compounds. After 5 h incubation at 37° C., 5% CO 2  in a humidified atmosphere, the plate of cells and compounds was centrifuged at 200×g for 5 min at RT. From each well, 5 μL of supernatant was transferred into corresponding wells of a white 384-well plate (Perkin Elmer, Cat. No. 6005620). To these supernatant-containing wells was added 10 μL of 5× Anti-Analyte Acceptor beads (50 μg/mL of AlphaLISA HiBlock Buffer) and incubated for 30 min at RT while shaking on an orbital plate shaker. To each well was added 10 μL of 5× Biotinylated Antibody Anti-analyte (5 nM in AlphaLISA HiBlock Buffer) and incubated on an orbital plate shaker for 60 min at RT or overnight at 4° C. To each well was added 25 μL of 2×SA-Donor beads (80 μg/mL in AlphaLISA HiBlock Buffer) and incubated for 30-45 min at RT in the dark while shaking on an orbital plate shaker. The plate was then read on a Perkin Elmer Envision (λ ex =680 nm, λ em =570 nm). The percent effect of the AlphaLISA signal at each compound concentration was calculated based on 30 uM cGAMP positive controls and 0.3% DMSO negative controls. The plot of percent effect versus the log of compound concentration was fit with a 4-parameter concentration response equation to calculate EC 50  values. The test compounds were tested at concentrations 30000, 10000, 3333, 1111, 370.4, 123.4, 41.2, 13.7, 4.6, and 1.5 nM with 0.3% residual DMSO. The control compound, cGAMP was tested at concentrations 100000, 33333, 11111, 3704, 1235, 412, 137, 46, and 15 nM with 0.3% residual DMSO. 
     Compounds of the disclosure were evaluated for IFN-β secretion in THP1 cell culture as described above. The following table tabulates the biological data for these compounds as percent activation relative to 2′3′-cGAMP at the 30 μM concentration. 
     
       
         
           
               
             
               
                 TABLE 14 
               
             
            
               
                   
               
               
                 IFN-β secretion in THP1 cell culture (5 h) 
               
            
           
           
               
               
               
            
               
                   
                   
                 % Effect at 30 μM 
               
               
                   
                 Compound 
                 relative to 2′3′-cGAMP 
               
               
                   
                   
               
            
           
           
               
               
               
            
               
                   
                 Example 1 
                 154 
               
               
                   
                 Example 2 
                 148 
               
               
                   
                 Example 3 
                 149 
               
               
                   
                 Example 4 
                 171 
               
               
                   
                 Example 5 
                 152 
               
               
                   
                 Example 6 
                 114 
               
               
                   
                 Example 7 
                 112 
               
               
                   
                 Example 8 
                 98 
               
               
                   
                 Example 9 
                 143 
               
               
                   
                 Example 10 
                 126 
               
               
                   
                 Example 11 
                 169 
               
               
                   
                 Example 12 
                 89 
               
               
                   
                 Example 13 
                 39 
               
               
                   
                 Example 14 
                 139 
               
               
                   
                 Example 15 
                 39 
               
               
                   
                 Example 16 
                 57 
               
               
                   
                 Example 17 
                 81 
               
               
                   
                 Example 18 
                 74 
               
               
                   
                 Example 19 
                 49 
               
               
                   
                 Example 20 
                 159 
               
               
                   
                 Example 21 
                 142 
               
               
                   
                 Example 22 
                 109 
               
               
                   
                 Example 23 
                 125 
               
               
                   
                 Example 24 
                 90 
               
               
                   
                 Example 25 
                 145 
               
               
                   
                 Example 26 
                 150 
               
               
                   
                 Example 27 
                 164 
               
               
                   
                 Example 28 
                 60 
               
               
                   
                 Example 29 
                 25 
               
               
                   
                 Example 30 
                 131 
               
               
                   
                 Example 31 
                 100 
               
               
                   
                 Example 32 
                 125 
               
               
                   
                 Example 33 
                 200 
               
               
                   
                 Example 34 
                 125 
               
               
                   
                 Example 35 
                 51 
               
               
                   
                 Example 36 
                 120 
               
               
                   
                 Example 37 
                 57 
               
               
                   
                 Example 38 
                 123 
               
               
                   
                 Example 39 
                 74 
               
               
                   
                 Example 40 
                 77 
               
               
                   
                 Example 41 
                 8 
               
               
                   
                 Example 42 
                 101 
               
               
                   
                 Example 43 
                 130 
               
               
                   
                 Example 44 
                 135 
               
               
                   
                 Example 45 
                 161 
               
               
                   
                 Example 46 
                 143 
               
               
                   
                 Example 47 
                 141 
               
               
                   
                 Example 48 
                 104 
               
               
                   
                 Example 49 
                 74 
               
               
                   
                 Example 50 
                 85 
               
               
                   
                 Example 51 
                 36 
               
               
                   
                 Example 52 
                 143 
               
               
                   
                 Example 53 
                 127 
               
               
                   
                 Example 54 
                 83 
               
               
                   
                 Example 55 
                 83 
               
               
                   
                 Example 56 
                 64 
               
               
                   
                 Example 57 
                 7 
               
               
                   
                 Example 58 
                 92 
               
               
                   
                 Example 59 
                 76 
               
               
                   
                 Example 60 
                 12 
               
               
                   
                 Example 61 
                 34 
               
               
                   
                 Example 62 
                 68 
               
               
                   
                 Example 63 
                 83 
               
               
                   
                 Example 64 
                 93 
               
               
                   
                 Example 65 
                 87 
               
               
                   
                 Example 66 
                 54 
               
               
                   
                 Example 67 
                 111 
               
               
                   
                 Example 68 
                 72 
               
               
                   
                 Example 69 
                 31 
               
               
                   
                 Example 70 
                 100 
               
               
                   
                 Example 71 
                 113 
               
               
                   
                 Example 72 
                 102 
               
               
                   
                 Example 73 
                 5 
               
               
                   
                 Example 74 
                 57 
               
               
                   
                 Example 75 
                 96 
               
               
                   
                 Example 76 
                 39 
               
               
                   
                 Example 77 
                 39 
               
               
                   
                 Example 78 
                 162 
               
               
                   
                 Example 79 
                 145 
               
               
                   
                 Example 80 
                 234 
               
               
                   
                 Example 81 
                 138 
               
               
                   
                 Example 82 
                 111 
               
               
                   
                 Example 83 
                 133 
               
               
                   
                 Example 84 
                 128 
               
               
                   
                 Example 85 
                 154 
               
               
                   
                 Example 86 
                 137 
               
               
                   
                 Example 87 
                 99 
               
               
                   
                 Example 88 
                 54 
               
               
                   
                 Example 89 
                 119 
               
               
                   
                 Example 90 
                 117 
               
               
                   
                 Example 91 
                 106 
               
               
                   
                 Example 92 
                 62 
               
               
                   
                 Example 93 
                 155 
               
               
                   
                 Example 94 
                 138 
               
               
                   
                 Example 95 
                 118 
               
               
                   
                 Example 96 
                 67 
               
               
                   
                 Example 97 
                 113 
               
               
                   
                 Example 98 
                 54 
               
               
                   
                 Example 99 
                 135 
               
               
                   
                 Example 100 
                 35 
               
               
                   
                 Example 101 
                 129 
               
               
                   
                 Example 102 
                 132 
               
               
                   
                 Example 103 
                 114 
               
               
                   
                 Example 104 
                 154 
               
               
                   
                 Example 105 
                 137 
               
               
                   
                 Example 106 
                 208 
               
               
                   
                 Example 107 
                 171 
               
               
                   
                 Example 108 
                 15 
               
               
                   
                 Example 109 
                 151 
               
               
                   
                 Example 110 
                 181 
               
               
                   
                 Example 111 
                 200 
               
               
                   
                 Example 112 
                 33 
               
               
                   
                 Example 113 
                 154 
               
               
                   
                 Example 114 
                 163 
               
               
                   
                 Example 115 
                 177 
               
               
                   
                 Example 116 
                 149 
               
               
                   
                 Example 117 
                 211 
               
               
                   
                 Example 118 
                 174 
               
               
                   
                 Example 119 
                 151 
               
               
                   
                 Example 120 
                 72 
               
               
                   
                 Example 121 
                 108 
               
               
                   
                 Example 122 
                 75 
               
               
                   
                 Example 123 
                 128 
               
               
                   
                 Example 124 
                 128 
               
               
                   
                 Example 125 
                 138 
               
               
                   
                 Example 126 
                 167 
               
               
                   
                 Example 127 
                 145 
               
               
                   
                 Example 128 
                 146 
               
               
                   
                 Example 129 
                 33 
               
               
                   
                 Example 130 
                 215 
               
               
                   
                 Example 131 
                 238 
               
               
                   
                 Example 132 
                 150 
               
               
                   
                 Example 133 
                 117 
               
               
                   
                 Example 134 
                 138 
               
               
                   
                 Example 135 
                 43 
               
               
                   
                 Example 136 
                 131 
               
               
                   
                 Example 137 
                 124 
               
               
                   
                 Example 138 
                 51 
               
               
                   
                 Example 139 
                 110 
               
               
                   
                 Example 140 
                 96 
               
               
                   
                 Example 141 
                 111 
               
               
                   
                 Example 142 
                 111 
               
               
                   
                 Example 143 
                 157 
               
               
                   
                 Example 144 
                 114 
               
               
                   
                 Example 145 
                 141 
               
               
                   
                 Example 146 
                 59 
               
               
                   
                 Example 147 
                 146 
               
               
                   
                 Example 148 
                 13 
               
               
                   
                 Example 149 
                 8 
               
               
                   
                 Example 150 
                 89 
               
               
                   
                 Example 151 
                 57 
               
               
                   
                 Example 152 
                 16 
               
               
                   
                 Example 153 
                 234 
               
               
                   
                 Example 154 
                 198 
               
               
                   
                 Example 155 
                 139 
               
               
                   
                 Example 156 
                 119 
               
               
                   
                 Example 157 
                 151 
               
               
                   
                 Example 158 
                 123 
               
               
                   
                 Example 159 
                 140 
               
               
                   
                 Example 160 
                 12 
               
               
                   
                 Example 161 
                 130 
               
               
                   
                 Example 162 
                 116 
               
               
                   
                 Example 163 
                 127 
               
               
                   
                 Example 164 
                 41 
               
               
                   
                 Example 165 
                 245 
               
               
                   
                 Example 166 
                 143 
               
               
                   
                 Example 167 
                 278 
               
               
                   
                 Example 168 
                 164 
               
               
                   
                 Example 169 
                 117 
               
               
                   
                 Example 170 
                 134 
               
               
                   
                 Example 171 
                 142 
               
               
                   
                 Example 172 
                 26 
               
               
                   
                 Example 173 
                 142 
               
               
                   
                 Example 174 
                 5 
               
               
                   
                 Example 175 
                 120 
               
               
                   
                 Example 176 
                 114 
               
               
                   
                 Example 177 
                 180 
               
               
                   
                 Example 178 
                 111 
               
               
                   
                 Example 179 
                 66 
               
               
                   
                 Example 180 
                 143 
               
               
                   
                 Example 181 
                 178 
               
               
                   
                 Example 182 
                 47 
               
               
                   
                 Example 183 
                 23 
               
               
                   
                 Example 184 
                 108 
               
               
                   
                 Example 185 
                 61 
               
               
                   
                 Example 186 
                 179 
               
               
                   
                 Example 187 
                 134 
               
               
                   
                 Example 188 
                 251 
               
               
                   
                 Example 189 
                 93 
               
               
                   
                 Example 190 
                 200 
               
               
                   
                 Example 191 
                 516 
               
               
                   
                 Example 192 
                 50 
               
               
                   
                 Example 193 
                 399 
               
               
                   
                 Example 194 
                 258 
               
               
                   
                 Example 195 
                 61 
               
               
                   
                 Example 196 
                 14 
               
               
                   
                 Example 197 
                 237 
               
               
                   
                 Example 198 
                 205 
               
               
                   
                 Example 199 
                 139 
               
               
                   
                 Example 200 
                 219 
               
               
                   
                 Example 201 
                 222 
               
               
                   
                 Example 202 
                 171 
               
               
                   
                 Example 203 
                 194 
               
               
                   
                 Example 204 
                 101 
               
               
                   
                 Example 205 
                 132 
               
               
                   
                 Example 206 
                 166 
               
               
                   
                 Example 207 
                 189 
               
               
                   
                 Example 208 
                 163 
               
               
                   
                 Example 209 
                 170 
               
               
                   
                 Example 210 
                 178 
               
               
                   
                 Example 211 
                 114 
               
               
                   
                 Example 212 
                 285 
               
               
                   
                 Example 213 
                 255 
               
               
                   
                 Example 214 
                 224 
               
               
                   
                 Example 215 
                 277 
               
               
                   
                 Example 216 
                 170 
               
               
                   
                 Example 217 
                 70 
               
               
                   
                 Example 218 
                 152 
               
               
                   
                 Example 219 
                 142 
               
               
                   
                 Example 220 
                 6 
               
               
                   
                 Example 221 
                 405 
               
               
                   
                 Example 222 
                 171 
               
               
                   
                 Example 223 
                 11 
               
               
                   
                 Example 224 
                 288 
               
               
                   
                 Example 225 
                 467 
               
               
                   
                 Example 226 
                 439 
               
               
                   
                 Example 227 
                 290 
               
               
                   
                 Example 228 
                 6 
               
               
                   
                 Example 229 
                 6 
               
               
                   
                 Example 230 
                 116 
               
               
                   
                 Example 231 
                 189 
               
               
                   
                 Example 232 
                 21 
               
               
                   
                 Example 233 
                 254 
               
               
                   
                 Example 234 
                 75 
               
               
                   
                 Example 235 
                 262 
               
               
                   
                 Example 236 
                 5 
               
               
                   
                 Example 237 
                 222 
               
               
                   
                 Example 238 
                 183 
               
               
                   
                 Example 239 
                 164 
               
               
                   
                 Example 240 
                 141 
               
               
                   
                 Example 241 
                 300 
               
               
                   
                 Example 242 
                 156 
               
               
                   
                 Example 243 
                 165 
               
               
                   
                 Example 244 
                 96 
               
               
                   
                 Example 245 
                 234 
               
               
                   
                 Example 246 
                 217 
               
               
                   
                 Example 247 
                 166 
               
               
                   
                 Example 248 
                 42 
               
               
                   
                 Example 249 
                 106 
               
               
                   
                 Example 250 
                 6 
               
               
                   
                 Example 251 
                 175 
               
               
                   
                 Example 252 
                 23 
               
               
                   
                 Example 253 
                 73 
               
               
                   
                 Example 254 
                 131 
               
               
                   
                 Example 255 
                 49 
               
               
                   
                 Example 256 
                 149 
               
               
                   
                 Example 257 
                 8 
               
               
                   
                 Example 258 
                 120 
               
               
                   
                 Example 259 
                 91 
               
               
                   
                 Example 260 
                 113 
               
               
                   
                 Example 261 
                 90 
               
               
                   
                 Example 262 
                 108 
               
               
                   
                 Example 263 
                 114 
               
               
                   
                 Example 264 
                 123 
               
               
                   
                 Example 265 
                 25 
               
               
                   
                 Example 266 
                 168 
               
               
                   
                 Example 267 
                 5 
               
               
                   
                 Example 268 
                 181 
               
               
                   
                 Example 269 
                 109 
               
               
                   
                 Example 270 
                 235 
               
               
                   
                 Example 271 
                 229 
               
               
                   
                 Example 272 
                 44 
               
               
                   
                 Example 273 
                 85 
               
               
                   
                 Example 274 
                 124 
               
               
                   
                 Example 275 
                 157 
               
               
                   
                 Example 276 
                 45 
               
               
                   
                 Example 277 
                 174 
               
               
                   
                 Example 278 
                 68 
               
               
                   
                 Example 279 
                 160 
               
               
                   
                 Example 280 
                 191 
               
               
                   
                 Example 281 
                 8 
               
               
                   
                 Example 282 
                 39 
               
               
                   
                 Example 283 
                 288 
               
               
                   
                 Example 284 
                 260 
               
               
                   
                 Example 285 
                 195 
               
               
                   
                 Example 286 
                 16 
               
               
                   
                 Example 287 
                 202 
               
               
                   
                 Example 288 
                 153 
               
               
                   
                 Example 289 
                 58 
               
               
                   
                 Example 290 
                 90 
               
               
                   
                 Example 291 
                 98 
               
               
                   
                 Example 292 
                 114 
               
               
                   
                 Example 293 
                 86 
               
               
                   
                 Example 294 
                 84 
               
               
                   
                 Example 295 
                 70 
               
               
                   
                 Example 296 
                 92 
               
               
                   
                 Example 297 
                 176 
               
               
                   
                 Example 298 
                 121 
               
               
                   
                 Example 299 
                 5 
               
               
                   
                 Example 300 
                 86 
               
               
                   
                 Example 301 
                 107 
               
               
                   
                 Example 302 
                 103 
               
               
                   
                 Example 303 
                 106 
               
               
                   
                 Example 304 
                 104 
               
               
                   
                 Example 305 
                 50 
               
               
                   
                 Example 306 
                 153 
               
               
                   
                 Example 307 
                 174 
               
               
                   
                 Example 308 
                 132 
               
               
                   
                 Example 309 
                 232 
               
               
                   
                 Example 310 
                 117 
               
               
                   
                 Example 311 
                 9 
               
               
                   
                 Example 312 
                 90 
               
               
                   
                 Example 313 
                 117 
               
               
                   
                 Example 314 
                 143 
               
               
                   
                 Example 315 
                 92 
               
               
                   
                 Example 316 
                 12 
               
               
                   
                 Example 317 
                 107 
               
               
                   
                 Example 318 
                 150 
               
               
                   
                 Example 319 
                 143 
               
               
                   
                 Example 320 
                 115 
               
               
                   
                 Example 321 
                 36 
               
               
                   
                 Example 322 
                 41 
               
               
                   
                 Example 323 
                 92 
               
               
                   
                 Example 324 
                 99 
               
               
                   
                 Example 325 
                 10 
               
               
                   
                 Example 326 
                 34 
               
               
                   
                 Example 327 
                 126 
               
               
                   
                 Example 328 
                 99 
               
               
                   
                 Example 329 
                 105 
               
               
                   
                 Example 330 
                 67 
               
               
                   
                 Example 331 
                 116 
               
               
                   
                 Example 332 
                 113 
               
               
                   
                 Example 333 
                 10 
               
               
                   
                 Example 334 
                 66 
               
               
                   
                 Example 335 
                 60 
               
               
                   
                 Example 336 
                 85 
               
               
                   
                 Example 337 
                 204 
               
               
                   
                 Example 338 
                 219 
               
               
                   
                 Example 339 
                 175 
               
               
                   
                 Example 340 
                 306 
               
               
                   
                 Example 341 
                 7 
               
               
                   
                 Example 342 
                 23 
               
               
                   
                 Example 343 
                 255 
               
               
                   
                 Example 344 
                 337 
               
               
                   
                 Example 345 
                 144 
               
               
                   
                 Example 346 
                 182 
               
               
                   
                 Example 347 
                 225 
               
               
                   
                 Example 348 
                 8 
               
               
                   
                   
               
            
           
         
       
     
     It will be appreciated that various of the above-discussed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.