# Patent

## Title
Inhibitors of histone deacetylase and prodrugs thereof

## Abstract

The invention relates to the inhibition of histone deacetylase. The invention provides compounds, prodrugs thereof, and methods for inhibiting histone deacetylase enzymatic activity. The invention also provides compositions and methods for treating cell proliferative diseases and conditions.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of priority of U.S. Application No. 60/870,768, filed Dec. 19, 2006.


BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the inhibition of histone deacetylase. More particularly, the invention relates to compounds and prodrugs thereof that inhibit, histone deacetylase enzymatic activity. The invention also relates to methods of inhibiting histone deacetylase enzymatic activity.
2. Summary of the Related Art
In eukaryotic cells, nuclear DNA associates with histones to form a compact complex called chromatin. The histones constitute a family of basic proteins which are generally highly conserved across eukaryotic species. The core histones, termed H2A, H2B, H3, and H4, associate to form a protein core. DNA winds around this protein core, with the basic amino acids of the histones interacting with the negatively charged phosphate groups of the DNA. Approximately 146 base pairs of DNA wrap around a histone core to make up a nucleosome particle, the repeating structural motif of chromatin.
Csordas, Biochem. J., 286: 23-38 (1990) teaches that histones are subject to posttranslational acetylation of the ε-amino groups of N-terminal lysine residues, a reaction that is catalyzed by histone acetyl transferase (HAT1). Acetylation neutralizes the positive charge of the lysine side chain, and is thought to impact chromatin structure. Indeed, Taunton et al., Science, 272: 408-411 (1996), teaches that access of transcription factors to chromatin templates is enhanced by histone hyperacetylation. Taunton et al. further teaches that an enrichment in underacetylated histone H4 has been found in transcriptionally silent regions of the genome.
Histone acetylation is a reversible modification, with deacetylation being catalyzed by a family of enzymes termed histone deacetylases (HDACs). Grozinger et al., Proc. Natl. Acad. Sci. USA, 96: 4868-4873 (1999), teaches that HDACs may be divided into two classes, the first represented by yeast Rpd3-like proteins, and the second represented by yeast Hda1-like proteins.
Histone deacetylases play an important role in gene regulation in mammalian cells. Gray and Ekstrom, Expr. Cell. Res. 262: 75-83 (2001); Zhou et al., Proc. Natl. Acad. Sci. USA 98: 10572-10577 (2001); Kao et al. J. Biol. Chem. 277: 187-193 (2002) and Gao et al. J. Biol. Chem. 277: 25748-25755 (2002) teach that there are 11 members of the histone deacetylase (HDAC) family. Another family of deacetylases involved in gene expression is the Sir2 family. Gray and Ekstrom, supra, teach that there are seven members of the Sir2 family in humans.
Class I human histone deacetylases include HDAC1, HDAC2, HDAC3 and HDAC8. The Class I enzymes are expressed in a wide variety of tissues and are reported to be localized in the nucleus. Class II human histone deacetylases include HDAC4, HDAC5, HDAC6, HDAC7, HDAC9 and HDAC10. The Class II enzymes have been described as limited in tissue distribution and they can shuttle between the nucleus and the cytoplasm. The Class II enzymes are further divided into Class Ia (HDAC4, HDAC5, HDAC7 and HDAC9) and Class IIb (HDAC6 and HDAC10). Recent classifications place HDAC11 in a class of its own.
Richon et al., Proc. Natl. Acad. Sci. USA, 95: 3003-3007 (1998), discloses that HDAC activity is inhibited by trichostatin A (TSA), a natural product isolated from Streptomyces hygroscopicus, and by a synthetic compound, suberoylanilide hydroxamic acid (SAHA). Yoshida and Beppu, Exper. Cell Res., 177: 122-131 (1988), teaches that TSA causes arrest of rat fibroblasts at the G1 and G2 phases of the cell cycle, implicating HDAC in cell cycle regulation. Indeed, Finnin et al., Nature, 401: 188-193 (1999), teaches that TSA and SAHA inhibit cell growth, induce terminal differentiation, and prevent the formation of tumors in mice.
U.S. Pat. No. RE39850, incorporated herein by reference, discloses compounds that inhibit HDAC activity for intervening in cell cycle regulation and therapeutic potential in the treatment of cell proliferative diseases or conditions. However, these compounds can exhibit poor bioavailability, thereby limiting their therapeutic potential. It is therefore desirable to also prepare bioavailable analogs of such active compounds.
SUMMARY OF THE INVENTION
The invention provides compounds, prodrugs and methods for treating diseases or conditions ameliorated by modulating HDAC activity, such as cell proliferative diseases, or fungal infection, by administering such prodrugs. In particular, the invention provides prodrug inhibitors of histone deacetylase enzymatic activity. These prodrugs are cleavable (e.g., hydrolysable) in a mammalian cell, a plant cell or fungal pathogen cell. Thus, also included within the scope of the present invention are products of the cleaved prodrugs, which include novel hydroxamate based compounds. For the purpose of clarity, a “prodrug compound” or “prodrug” of the present invention is intended to mean a non-cleaved compound as defined by Formula (1), (2) and (3). A “cleavage product” of the prodrug is intended to mean a prodrug compound from which the prodrug moiety has been removed.
In a first aspect, therefore, the invention provides prodrugs of inhibitors of histone deacetylase, the prodrugs having the formula (1):

Cy-L1-Ar—Y1—C(O)—N(Rx)—Z  (1)

and pharmaceutically acceptable salts thereof, wherein

    Cy is —H, cycloalkyl, aryl, heteroaryl, or heterocyclyl, any of which may be optionally substituted;
    L1 is —(CH2)m—W—, where m is 0, 1, 2, 3, or 4, and W is selected from the group consisting of —C(O)NH—, —S(O)2NH—, —NHC(O)—, —NHS(O)2—, and —NH—C(O)—NH—;
    Ar is arylene, wherein said arylene optionally may be additionally substituted and optionally may be fused to an aryl or heteroaryl ring, or to a saturated or partially unsaturated cycloalkyl or heterocyclic ring, any of which may be optionally substituted;
    Y1 is a chemical bond or a straight- or branched-chain saturated alkylene, wherein said alkylene may be optionally substituted;
    Z is —R20, —O—R20, —R21, or






     wherein —R20 is selected from the group consisting of —C(O)—R10, —C(O)O—R10, —R11, —CH(R12)—O—C(O)—R10, —C(O)—C[(R10)(R10′)]1-4—NH(R13), —S(O2)R10, —P(O)(OR10)(OR10), —C(O)—(CH2)n—CH(OH)—CH2—O—R10, —C(O)—O—(CH2)n—CH(OH)—CH2—O—R10 and —C(O)—(CH2)n—C(O)OR10, —C(O)—(CH2)1-4—C(OH)(COOR10)—(CH2)1-4—COOR10, —C(O)-[C(R14)(R14)]1-4—P(O)(OH)(OH), —C(O)—(CH2)1-4—N(R14)—C[═N(R10′)]-N(R10′)(R10′), —C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —C(O)—CH(NH2)—(CH2)1-6—COOH (preferably —C(O)—CH(NH2)—(CH2)—COOH), provided that the N to which Z is bound is not directly bonded to two O atoms; and further provided that (a) when Z is —R20 then Rx is —OH, and (b) when Z is —OR20 then Rx is —H;
    Rx is H or —OH;
    or
    Rx is absent and R20 forms an optionally substituted heterocyclic ring with the N to which it is attached;
    n is 0, 1, 2, 3, or 4, preferably 1, 2, 3, or 4;
    each R10 is independently selected from the group consisting of hydrogen, optionally substituted C1-C20 alkyl, optionally substituted C2-C20 alkenyl, optionally substituted C2-C20 alkynyl, optionally substituted C1-C20 alkoxycarbonyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkylalkyl, optionally substituted heterocycloalkylalkyl, optionally substituted arylalkyl, optionally substituted heteroarylalkyl, optionally substituted cycloalkylalkenyl, optionally substituted heterocycloalkylalkenyl, optionally substituted arylalkenyl, optionally substituted heteroarylalkenyl, optionally substituted cycloalkylalkynyl, optionally substituted heterocycloalkylalkynyl, optionally substituted arylalkynyl, optionally substituted heteroarylalkynyl, optionally substituted alkylcycloalkyl, optionally substituted alkylheterocycloalkyl, optionally substituted alkylaryl, optionally substituted alkylheteroaryl, optionally substituted alkenylcycloalkyl, optionally substituted alkenylheterocycloalkyl, optionally substituted alkenylaryl, optionally substituted alkenylheteroaryl, optionally substituted alkynylcycloalkyl, optionally substituted alkynylheterocycloalkyl, optionally substituted alkynylary, optionally substituted alkynylheteroaryl, a sugar residue, and an amino acid residue (preferably bonded through the carboxy terminus of the amino acid);
    each R10′ is independently hydrogen or C1-6alkyl, or
    R10 and R10′ together with the carbon atom to which they are attached form an optionally substituted spirocycloalkyl;
    R21 is a sugar or -amino acid-R3, wherein R13 is covalently bound to the N-terminus;
    R11 is selected from the group consisting of hydrogen, optionally substituted heterocycloalkyl, optionally substituted aryl, and optionally substituted heteroaryl;
    R12 is selected from hydrogen or alkyl; and
    R13 is selected from the group consisting of hydrogen, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-N(R10′)(R10′), —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-aryl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-heteroaryl, —C(O)-aryl, —C(O)-heteroaryl, an amino protecting group, and R10; and
    each R14 is independently selected from the group consisting of H, C1-C6alkyl and cycloalkyl, or two R4, together with the atom to which they are attached, form a cycloalkyl.


In a second embodiment, the invention provides prodrugs of inhibitors of histone deacetylase, the prodrugs having the formula (2):

Cy-L2-Ar—Y2—C(O)N(Rx)—Z  (2)

and pharmaceutically acceptable salts thereof, wherein

    Cy is H or is cycloalkyl, aryl, heteroaryl, or heterocyclyl, any of which may be optionally substituted, provided that Cy is not a (spirocycloalkyl)heterocyclyl;
    L2 is C1-C6 saturated alkylene, C2-C6 alkenylene or C2-C6 alkynylene, wherein the alkylene or alkenylene optionally may be substituted, and wherein one or two of the carbon atoms of the alkylene is optionally replaced by a heteroatomic moiety independently selected from the group consisting of O; NR′, R′ being alkyl, acyl, or hydrogen; S; S(O); or S(O)2;
    Ar is arylene, wherein said arylene optionally may be additionally substituted and optionally may be fused to an aryl or heteroaryl ring, or to a saturated or partially unsaturated cycloalkyl or heterocyclic ring, any of which may be optionally substituted;
    Y2 is a chemical bond or a straight- or branched-chain saturated alkylene, which may be optionally substituted, provided that the alkylene is not substituted with a substituent of the formula —C(O)R wherein R comprises an α-amino acyl moiety;
    Rx is H or —OH;
    Z is —R20, —O—R20, —R21, or






     wherein —R20 is selected from the group consisting of —C(O)—R10, —C(O)O—R10, —R11, —CH(R12)—O—C(O)—R10, —C(O)—C[(R10)(R10′)]1-4—NH(R3), —S(O2)R10, —P(O)(OR10)(OR10), —C(O)—(CH2)n—CH(OH)—CH2—O—R10, —C(O)—(CH2)1-4—C(OH)(COOR10)—(CH2)1-4—COOR10, —C(O)-[C(R14)(R14)]1-4—P(O)(OH)(OH), —C(O)—(CH2)1-4—N(R14)—C[═N(R10′)]-N(R10′)(R10′), —C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —C(O)—CH(NH2)—(CH2)1-6—COOH (preferably —C(O)—CH(NH2)—(CH2)—COOH), —C(O)—O—(CH2)n—CH(OH)—CH2—O—R10 and —C(O)—(CH2)n—C(O)OR10, provided that the N to which Z is bound is not directly bonded to two O atoms; and further provided that (a) when Z is —R20 then Rx is —OH, and (b) when Z is —OR20 then Rx is —H;
    or
    Rx is absent and R20 forms an optionally substituted heterocyclic ring with the N to which it is attached;
    n is 0, 1, 2, 3, or 4, preferably 1, 2, 3, or 4;
    each R10 is independently selected from the group consisting of hydrogen, optionally substituted C1-C20 alkyl, optionally substituted C2-C20 alkenyl, optionally substituted C2-C20 alkynyl, optionally substituted C1-C20 alkoxycarbonyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkylalkyl, optionally substituted heterocycloalkylalkyl, optionally substituted arylalkyl, optionally substituted heteroarylalkyl, optionally substituted cycloalkylalkenyl, optionally substituted heterocycloalkylalkenyl, optionally substituted arylalkenyl, optionally substituted heteroarylalkenyl, optionally substituted cycloalkylalkynyl, optionally substituted heterocycloalkylalkynyl, optionally substituted arylalkynyl, optionally substituted heteroarylalkynyl, optionally substituted alkylcycloalkyl, optionally substituted alkylheterocycloalkyl, optionally substituted alkylaryl, optionally substituted alkylheteroaryl, optionally substituted alkenylcycloalkyl, optionally substituted alkenylheterocycloalkyl, optionally substituted alkenylaryl, optionally substituted alkenylheteroaryl, optionally substituted alkynylcycloalkyl, optionally substituted alkynylheterocycloalkyl, optionally substituted alkynylary, optionally substituted alkynylheteroaryl, a sugar residue, and an amino acid residue (preferably bonded through the carboxy terminus of the amino acid);
    each R10′ is independently hydrogen or C1-6alkyl, or
    R10 and R10′ together with the carbon atom to which they are attached form an optionally substituted spirocycloalkyl;
    R21 is a sugar or -amino acid-R13, wherein R13 is covalently bound to the N-terminus;
    R11 is selected from the group consisting of hydrogen, optionally substituted heterocycloalkyl, optionally substituted aryl, and optionally substituted heteroaryl;
    R12 is selected from hydrogen or alkyl; and
    R13 is selected from the group consisting of hydrogen, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-N(R10′)(R10′), —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-aryl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-heteroaryl, —C(O)-aryl, —C(O)-heteroaryl, an amino protecting group, and R10; and
    each R14 is independently selected from the group consisting of H, C1-C6alkyl and cycloalkyl, or two R14, together with the atom to which they are attached, form a cycloalkyl.


In a third embodiment, the invention provides prodrugs of inhibitors of histone deacetylase, the prodrugs having the formula (3):

Cy-L3-Ar—Y3—C(O)N(Rx)—Z  (3)

and pharmaceutically acceptable salts thereof, wherein

    Cy is —H, cycloalkyl, aryl, heteroaryl, or heterocyclyl, any of which may be optionally substituted, provided that Cy is not a (spirocycloalkyl)heterocyclyl;
    L3 is selected from the group consisting of
    
        (a) —(CH2)m—W—, where m is 0, 1, 2, 3, or 4, and W is selected from the group consisting of —C(O)NH—, —S(O)2NH—, —NHC(O)—, —NHS(O)2—, and —NH—C(O)—NH—; and
        (b) C1-C6 alkylene or C2-C6 alkenylene, wherein the alkylene or alkenylene optionally may be substituted, and wherein one of the carbon atoms of the alkylene optionally may be replaced by O; NR′, R′ being alkyl, acyl, or hydrogen; S; S(O); or S(O)2;
    
    
    Ar is arylene, wherein said arylene optionally may be additionally substituted and optionally may be fused to an aryl or heteroaryl ring, or to a saturated or partially unsaturated cycloalkyl or heterocyclic ring, any of which may be optionally substituted; and
    Y3 is C2 alkenylene or C2 alkynylene, wherein one or both carbon atoms of the alkenylene optionally may be substituted with alkyl, aryl, alkaryl, or aralkyl;
    Rx is H or —OH;
    Z is —R20, —O—R20, —R21, or






     wherein —R20 is selected from the group consisting of —C(O)—R10, —C(O)O—R10, —R11, —CH(R12)—O—C(O)—R10, —C(O)—C[(R10)(R10′)]1-4—NH(R13), —S(O2)R10, —P(O)(OR10)(OR10), —C(O)—(CH2)n—CH(OH)—CH2—O—R10, —C(O)—(CH2)1-4—C(OH)(COOR10)—(CH2)1-4—COOR10, —C(O)-[C(R14)(R14)]1-4—P(O)(OH)(OH), —C(O)—(CH2)1-4—N(R14)—C [═N(R10′)]-N(R10′)(R10′), —C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —C(O)—CH(NH2)—(CH2)1-6—COOH (preferably —C(O)—CH(NH2)—(CH2)—COOH), —C(O)—O—(CH2)n—CH(OH)—CH2—O—R10 and —C(O)—(CH2)n—C(O)OR10, provided that the N to which Z is bound is not directly bonded to two O atoms; and further provided that (a) when Z is —R20 then Rx is —OH, and (b) when Z is —OR20 then Rx is —H;
    or
    Rx is absent and R20 forms an optionally substituted heterocyclic ring with the N to which it is attached;
    n is 0, 1, 2, or 4, preferably 1, 2, 3, or 4;
    each R10 is independently selected from the group consisting of hydrogen, optionally substituted C1-C20 alkyl, optionally substituted C2-C20 alkenyl, optionally substituted C2-C20 alkynyl, optionally substituted C1-C20 alkoxycarbonyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkylalkyl, optionally substituted heterocycloalkylalkyl, optionally substituted arylalkyl, optionally substituted heteroarylalkyl, optionally substituted cycloalkylalkenyl, optionally substituted heterocycloalkylalkenyl, optionally substituted arylalkenyl, optionally substituted heteroarylalkenyl, optionally substituted cycloalkylalkynyl, optionally substituted heterocycloalkylalkynyl, optionally substituted arylalkynyl, optionally substituted heteroarylalkynyl, optionally substituted alkylcycloalkyl, optionally substituted alkylheterocycloalkyl, optionally substituted alkylaryl, optionally substituted alkylheteroaryl, optionally substituted alkenylcycloalkyl, optionally substituted alkenylheterocycloalkyl, optionally substituted alkenylaryl, optionally substituted alkenylheteroaryl, optionally substituted alkynylcycloalkyl, optionally substituted alkynylheterocycloalkyl, optionally substituted alkynylary, optionally substituted alkynylheteroaryl, a sugar residue, and an amino acid residue (preferably bonded through the carboxy terminus of the amino acid);
    each R10′ is independently hydrogen or C1-6alkyl, or
    R10 and R10′ together with the carbon atom to which they are attached form an optionally substituted spirocycloalkyl;
    R21 is a sugar or -amino acid-R13, wherein R13 is covalently bound to the N-terminus;
    R11 is selected from the group consisting of hydrogen, optionally substituted heterocycloalkyl, optionally substituted aryl, and optionally substituted heteroaryl;
    R12 is selected from hydrogen or alkyl; and
    R13 is selected from the group consisting of hydrogen, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-N(R10′)(R10′), —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-aryl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-heteroaryl, —C(O)-aryl, —C(O)-heteroaryl, an amino protecting group, and R10; and
    each R14 is independently selected from the group consisting of H, C1-C6alkyl and cycloalkyl, or two R14, together with the atom to which they are attached, form a cycloalkyl.




DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention provides prodrugs, cleavage products thereof, and methods for inhibiting histone deacetylase enzymatic activity. The invention also provides compositions and methods for treating diseases or conditions ameliorated by modulating HDAC activity, such as cell proliferative diseases and conditions, and fungal infection. The patent and scientific literature referred to herein establishes knowledge that is available to those with skill in the art. The issued patents, applications, and references that are cited herein are hereby incorporated by reference to the same extent as if each was specifically and individually indicated to be incorporated by reference. In the case of inconsistencies, the present disclosure will prevail.
For purposes of the present invention, the following definitions will be used:
Unless otherwise indicated by context, the terms “histone deacetylase” and “HDAC” are intended to refer to any one of a family of enzymes that remove acetyl groups from the ε-amino groups of lysine residues at the N-terminus of a histone. Unless otherwise indicated by context, the term “histone” is meant to refer to any histone protein, including H1, H2A, H2B, H3, H4, and H5, from any species. Preferred histone deacetylases include class I and class II enzymes. Preferably the histone deacetylase is a human HDAC, including, but not limited to, HDAC-1, HDAC-2, HDAC-3, HDAC-4, HDAC-5, HDAC-6, HDAC-7, HDAC-8, HDAC-9, HDAC-10, and HDAC-11. In some other preferred embodiments, the histone deacetylase is derived from a protozoal or fungal source. Preferred fungi include, but are not limited to Saccharomyces cerevisiae, Candida spp. (such as C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, C. lusitaniae, C. dubliniensis), Aspergillus spp. (such as A. fumigatus, A. flavus, A. niger, A. terreus), Fusarium spp., Paecilomyces lilacinus, Rhizopus arrhizus and Coccidioides immitis. In certain preferred embodiments, the histone deacetylase is a fungal HDAC including, but not limited to Rpd3, Hos1, Hos2, Hda1, Hos3, Sir2, Hst, and homologs thereof. In preferred embodiments, a cleavage product of a prodrug compound of the present invention shows synergistic activity with an antifungal agent against a fungal species, preferably at concentrations of inhibitor not toxic to mammalian cells. Preferably such antifungal agents are azole antifungal agents (a large number of active antifungal agents have an azole functionality as part of their structure; such an antifungal agent is generally referred to as an “antifungal azole”, an “azole antifungal agent” or an “azole”). Such combinations, and compositions thereof, can be used to selectively treat fungal infection.
The term “antifungal agent” is intended to mean a substance capable of inhibiting or preventing the growth, viability and/or reproduction of a fungal cell. Preferable antifungal agents are those capable of preventing or treating a fungal infection in an animal or plant. A preferable antifungal agent is a broad spectrum antifungal agent. However, an antifungal agent can also be specific to one or more particular species of fungus.
Preferred antifungal agents are ergosterol synthesis inhibitors, and include, but are not limited to azoles and phenpropimorph. Other antifungal agents include, but are not limited to terbinafine. Preferred azoles include imidazoles and triazoles. Further preferred antifungal agents include, but are not limited to, ketoconazole, itroconazole, fluconazole, voriconazole, posaconazole, ravuconazole and miconazole. Like azoles, phenpropimorph is an ergosterol synthesis inhibitor, but acts on the ergosterol reductase (ERG24) step of the synthesis pathway. Terbinafine, is also an ergosterol inhibitor, but acts on the squalene eposidase (ERG1) step.
The term “histone deacetylase inhibitor” or “inhibitor of histone deacetylase” is used to identify a compound having a structure as defined herein, which is capable of interacting with a histone deacetylase and inhibiting its enzymatic activity. Inhibiting histone deacetylase enzymatic activity means reducing the ability of a histone deacetylase to remove an acetyl group from a histone. In some preferred embodiments, such reduction of histone deacetylase activity is at least about 50%, more preferably at least about 75%, and still more preferably at least about 90%. In other preferred embodiments, histone deacetylase activity is reduced by at least 95% and more preferably by at least 99%.
Preferably, such inhibition is specific, i.e., the histone deacetylase inhibitor reduces the ability of a histone deacetylase to remove an acetyl group from a histone at a concentration that is lower than the concentration of the inhibitor that is required to produce another, unrelated biological effect. Preferably, the concentration of the inhibitor required for histone deacetylase inhibitory activity is at least 2-fold lower, more preferably at least 5-fold lower, even more preferably at least 10-fold lower, and most preferably at least 20-fold lower than the concentration required to produce an unrelated biological effect. In certain preferred embodiments of the present invention, cleavage (e.g., hydrolysis) of the prodrug releases a compound (a cleavage (e.g., hydrolyzation) product) which is an inhibitor of histone deacetylase that is more active against a fungal histone decetylase than against a mammalian histone deacetylase. In certain preferred embodiments of the present invention, the inhibitor of histone deacetylase is specific for a fungal histone deacetylase.
The terms “treating”, “treatment”, or the like, as used herein covers the treatment of a disease-state in an animal and includes at least one of: (i) preventing the disease-state from occurring, in particular, when such animal is predisposed to the disease-state but has not yet developed symptoms of having it; (ii) inhibiting the disease-state, i.e., partially or completely arresting its development; (iii) relieving the disease-state, i.e., causing regression of symptoms of the disease-state, or ameliorating a symptom of the disease; and (iv) reversal or regression of the disease-state, preferably eliminating or curing of the disease. In a preferred embodiment the terms “treating”, “treatment”, or the like, covers the treatment of a disease-state in an animal and includes at least one of (ii), (iii) and (iv) above. In a preferred embodiment of the present invention the animal is a mammal, preferably a primate, more preferably a human. As is known in the art, adjustments for systemic versus localized delivery, age, body weight, general health, sex, diet, time of administration, drug interaction and the severity of the condition may be necessary, and will be ascertainable with routine experimentation by one of ordinary skill in the art.
For simplicity, chemical moieties are defined and referred to throughout primarily as univalent chemical moieties (e.g., alkyl, aryl, etc.). Nevertheless, such terms are also used to convey corresponding multivalent moieties under the appropriate structural circumstances clear to those skilled in the art. For example, while an “alkyl” moiety generally refers to a monovalent radical (e.g. CH3—CH2—), in certain circumstances a bivalent linking moiety can be “alkyl,” in which case those skilled in the art will understand the alkyl to be a divalent radical (e.g., —CH2—CH2—), which is equivalent to the term “alkylene.” (Similarly, in circumstances in which a divalent moiety is required and is stated as being “aryl,” those skilled in the art will understand that the term “aryl” refers to the corresponding divalent moiety, arylene). All atoms are understood to have their normal number of valences for bond formation (i.e., 4 for carbon, 3 for N, 2 for O, and 2, 4, or 6 for S, depending on the oxidation state of the S). On occasion a moiety may be defined, for example, as (A)a-B—, wherein a is 0 or 1. In such instances, when a is 0 the moiety is B— and when a is 1 the moiety is A-B—.
For simplicity, reference to a “Cn—Cm” heterocyclyl or “Cn—Cm” heteroaryl means a heterocyclyl or heteroaryl having from “n” to “m” annular atoms, where “n” and “m” are integers. Thus, for example, a C5-C6-heterocyclyl is a 5- or 6-membered ring having at least one heteroatom, and includes pyrrolidinyl (C5) and piperidinyl (C6); C6-heteroaryl includes, for example, pyridyl and pyrimidyl.
The term “hydrocarbyl” refers to a straight, branched, or cyclic alkyl, alkenyl, or alkynyl, each as defined herein. A “C0” hydrocarbyl is used to refer to a covalent bond. Thus, “C0-C3-hydrocarbyl” includes a covalent bond, methyl, ethyl, ethenyl, ethynyl, propyl, propenyl, propynyl, and cyclopropyl.
The term “alkyl” is intended to mean a straight or branched chain aliphatic group having from 1 to 12 carbon atoms, preferably 1-8 carbon atoms, and more preferably 1-6 carbon atoms. Other preferred alkyl groups have from 2 to 12 carbon atoms, preferably 2-8 carbon atoms and more preferably 2-6 carbon atoms. Preferred alkyl groups include, without limitation, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, and hexyl. A “C0” alkyl (as in “C0-C3-alkyl”) is a covalent bond.
The term “alkenyl” is intended to mean an unsaturated straight or branched chain aliphatic group with one or more carbon-carbon double bonds, having from 2 to 12 carbon atoms, preferably 2-8 carbon atoms, and more preferably 2-6 carbon atoms. Preferred alkenyl groups include, without limitation, ethenyl, propenyl, butenyl, pentenyl, and hexenyl.
The term “alkynyl” is intended to mean an unsaturated straight or branched chain aliphatic group with one or more carbon-carbon triple bonds, having from 2 to 12 carbon atoms, preferably 2-8 carbon atoms, and more preferably 2-6 carbon atoms. Preferred alkynyl groups include, without limitation, ethynyl, propynyl, butynyl, pentynyl, and hexynyl.
The terms “alkylene,” “alkenylene,” or “alkynylene” as used herein are intended to mean an alkyl, alkenyl, or alkynyl group, respectively, as defined hereinabove, that is positioned between and serves to connect two other chemical groups. Preferred alkylene groups include, without limitation, methylene, ethylene, propylene, and butylene. Preferred alkenylene groups include, without limitation, ethenylene, propenylene, and butenylene. Preferred alkynylene groups include, without limitation, ethynylene, propynylene, and butynylene.
The term “cycloalkyl” is intended to mean a saturated or unsaturated mono-, bi, tri- or poly-cyclic hydrocarbon group having about 3 to 15 carbons, preferably having 3 to 12 carbons, preferably 3 to 8 carbons, and more preferably 3 to 6 carbons. In certain preferred embodiments, the cycloalkyl group is fused to an aryl, heteroaryl or heterocyclic group. Preferred cycloalkyl groups include, without limitation, cyclopenten-2-enone, cyclopenten-2-enol, cyclohex-2-enone, cyclohex-2-enol, cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cycloheptyl, and cyclooctyl.
The term “heteroalkyl” is intended to mean a saturated or unsaturated, straight or branched chain aliphatic group, wherein one or more carbon atoms in the chain are independently replaced by a heteroatom selected from the group consisting of O, S(O)0-2, N and N(R33).
The term “aryl” is intended to mean a mono-, bi-, tri- or polycyclic C6-C14 aromatic moiety, preferably comprising one to three aromatic rings. Preferably, the aryl group is a C6-C10 aryl group, more preferably a C6 aryl group. Preferred aryl groups include, without limitation, phenyl, naphthyl, anthracenyl, and fluorenyl.
The terms “aralkyl” or “arylalkyl” is intended to mean a group comprising an aryl group covalently linked to an alkyl group. If an aralkyl group is described as “optionally substituted”, it is intended that either or both of the aryl and alkyl moieties may independently be optionally substituted or unsubstituted. Preferably, the aralkyl group is (C1-C6)alk(C6-C10)aryl, including, without limitation, benzyl, phenethyl, and naphthylmethyl. For simplicity, when written as “arylalkyl” this term, and terms related thereto, is intended to indicate the order of groups in a compound as “aryl-alkyl”. Similarly, “alkyl-aryl” is intended to indicate the order of the groups in a compound as “alkyl-aryl”.
The terms “heterocyclyl”, “heterocyclic” or “heterocycle” are intended to mean a group which is a mono-, bi-, or polycyclic structure having from about 3 to about 14 atoms, wherein one or more atoms are independently selected from the group consisting of N, O, and S. The ring structure may be saturated, unsaturated or partially unsaturated. In certain preferred embodiments, the heterocyclic group is non-aromatic. In a bicyclic or polycyclic structure, one or more rings may be aromatic; for example one ring of a bicyclic heterocycle or one or two rings of a tricyclic heterocycle may be aromatic, as in indan and 9,10-dihydro anthracene. Preferred heterocyclic groups include, without limitation, epoxy, aziridinyl, tetrahydrofuranyl, pyrrolidinyl, piperidinyl, piperazinyl, thiazolidinyl, oxazolidinyl, oxazolidinonyl, and morpholino. In certain preferred embodiments, the heterocyclic group is fused to an aryl, heteroaryl, or cycloalkyl group. Examples of such fused heterocycles include, without limitation, tetrahydroquinoline and dihydrobenzofuran. Specifically excluded from the scope of this term are compounds where an annular O or S atom is adjacent to another O or S atom.
In certain preferred embodiments, the heterocyclic group is a heteroaryl group. As used herein, the term “heteroaryl” is intended to mean a mono-, bi-, tri- or polycyclic group having 5 to 14 ring atoms, preferably 5, 6, 9, or 10 ring atoms; having 6, 10, or 14 pi electrons shared in a cyclic array; and having, in addition to carbon atoms, between one or more heteroatoms independently selected from the group consisting of N, O, and S. For example, a heteroaryl group may be pyrimidinyl, pyridinyl, benzimidazolyl, thienyl, benzothiazolyl, benzofuranyl and indolinyl. Preferred heteroaryl groups include, without limitation, thienyl, benzothienyl, furyl, benzofuryl, dibenzofuryl, pyrrolyl, imidazolyl, pyrazolyl, pyridyl, pyrazinyl, pyrimidinyl, indolyl, quinolyl, isoquinolyl, quinoxalinyl, tetrazolyl, oxazolyl, thiazolyl, and isoxazolyl.
The terms “arylene,” “heteroarylene,” or “heterocyclylene” are intended to mean an aryl, heteroaryl, or heterocyclyl group, respectively, as defined hereinabove, that is positioned between and serves to connect two other chemical groups.
Preferred heterocyclyls and heteroaryls include, but are not limited to, acridinyl, azocinyl, benzimidazolyl, benzofuranyl, benzothiofuranyl, benzothiophenyl, benzoxazolyl, benzthiazolyl, benztriazolyl, benztetrazolyl, benzisoxazolyl, benzisothiazolyl, benzimidazolinyl, carbazolyl, 4aH-carbazolyl, carbolinyl, chromanyl, chromenyl, cinnolinyl, decahydroquinolinyl, 2H,6H-1,5,2-dithiazinyl, dihydrofuro[2,3-b]tetrahydrofuran, furanyl, furyl, furazanyl, imidazolidinyl, imidazolinyl, imidazolyl, 1H-indazolyl, indolenyl, indolinyl, indolizinyl, indolyl, 3H-indolyl, isobenzofuranyl, isochromanyl, isoindazolyl, isoindolinyl, isoindolyl, isoquinolinyl, isothiazolyl, isoxazolyl, methylenedioxyphenyl, morpholinyl, naphthyridinyl, octahydroisoquinolinyl, oxadiazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, oxazolidinyl, oxazolyl, oxazolidinyl, pyrimidinyl, phenanthridinyl, phenanthrolinyl, phenazinyl, phenothiazinyl, phenoxathiinyl, phenoxazinyl, phthalazinyl, piperazinyl, piperidinyl, piperidonyl, 4-piperidonyl, piperonyl, pteridinyl, purinyl, pyranyl, pyrazinyl, pyrazolidinyl, pyrazolinyl, pyrazolyl, pyridazinyl, pyridooxazole, pyridoimidazole, pyridothiazole, pyridinyl, pyridyl, pyrimidinyl, pyrrolidinyl, pyrrolinyl, 2H-pyrrolyl, pyrrolyl, quinazolinyl, quinolinyl, 4H-quinolizinyl, quinoxalinyl, quinuclidinyl, tetrahydrofuranyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl, tetrazolyl, 6H-1,2,5-thiadiazinyl, thiadiazolyl (e.g., 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl), thianthrenyl, thiazolyl, thienyl, thienothiazolyl, thienooxazolyl, thienoimidazolyl, thiophenyl, triazinyl, triazolyl (e.g., 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,5-triazolyl, 1,3,4-triazolyl), and xanthenyl.
Aromatic polycycles include, but are not limited to, bicyclic and tricyclic fused ring systems, including for example naphthyl.
Non-aromatic polycycles include, but are not limited to, bicyclic and tricyclic fused ring systems where each ring can be 4-9 membered and each ring can containing zero, 1 or more double and/or triple bonds. Suitable examples of non-aromatic polycycles include, but are not limited to, decalin, octahydroindene, perhydrobenzocycloheptene and perhydrobenzo-[f]-azulene.
Polyheteroaryl groups include bicyclic and tricyclic fused rings systems where each ring can independently be 5 or 6 membered and contain one or more heteroatom, for example, 1, 2, 3 or 4 heteroatoms, independently chosen from O, N and S such that the fused ring system is aromatic. Suitable examples of polyheteroaryl ring systems include quinoline, isoquinoline, pyridopyrazine, pyrrolopyridine, furopyridine, indole, benzofuran, benzothiofuran, benzindole, benzoxazole, pyrroloquinoline, and the like.
Non-aromatic polyheterocyclic groups include but are not limited to bicyclic and tricyclic ring systems where each ring can be 4-9 membered, contain one or more heteratom, for example 1, 2, 3 or 4 heteratoms, independently chosen from O, N and S, and contain zero, or one or more C—C double or triple bonds. Suitable examples of non-aromatic polyheterocycles include but are not limited to, hexitol, cis-perhydro-cyclohepta[b]pyridinyl, decahydro-benzo[f][1,4]oxazepinyl, 2,8-dioxabicyclo[3.3.0]octane, hexahydro-thieno[3,2-b]thiophene, perhydropyrrolo[3,2-b]pyrrole, perhydronaphthyridine, perhydrop-1H-dicyclopenta[b,e]pyran.
Mixed aryl and non-aryl polyheterocycle groups include but are not limited to bicyclic and tricyclic fused ring systems where each ring can be 4-9 membered, contain one or more heteroatom independently chosen from O, N and S and at least one of the rings must be aromatic. Suitable examples of mixed aryl and non-aryl polyheteorcycles include 2,3-dihydroindole, 1,2,3,4-tetrahydroquinoline, 5,11-dihydro-10H-dibenz[b,e][1,4]diazepine, 5H-dibenzo[b,e][1,4]diazepine, 1,2-dihydropyrrolo[3,4-b][1,5]benzodiazepine, 1,5-dihydropyrido[2,3-b][1,4]diazepin-4-one, 1,2,3,4,6,11-hexhydro-benzo[b]pyrido[2,3-e][1,4]diazepine-5-one, methylenedioxyphenyl, bis-methylenedioxyphenyl, 1,2,3,4-tetrahydronaphthalene, dibenzosuberane dihydroanthracene and 9H-fluorene.
As employed herein, and unless stated otherwise, when a moiety (e.g., alkyl, heteroalkyl, cycloalkyl, aryl, heteroaryl, heterocyclyl, etc.) is described as “optionally substituted” it is meant that the group optionally has from one to four, preferably from one to three, more preferably one or two, non-hydrogen substituents. Suitable substituents include, without limitation, halo, hydroxy, oxo (e.g., an annular —CH— substituted with oxo is —C(O)—) nitro, halohydrocarbyl, hydrocarbyl, alkyl, cycloalkyl, heterocyclyl, aryl, heteroaryl, aralkyl, alkoxy, aryloxy, amino, acylamino, alkylcarbamoyl, arylcarbamoyl, aminoalkyl, acyl, carboxy, hydroxyalkyl, alkanesulfonyl, arenesulfonyl, alkanesulfonamido, arenesulfonamido, aralkylsulfonamido, alkylcarbonyl, acyloxy, cyano, and ureido groups. Preferred substituents, which are themselves not further substituted (unless expressly stated otherwise) are:

    
    
        (a) halo, cyano, oxo, carboxy, formyl, nitro, amino, amidino, guanidino,
        (b) C1-C5 alkyl or alkenyl or arylalkyl imino, carbamoyl, azido, carboxamido, mercapto, hydroxy, hydroxyalkyl, alkylaryl, arylalkyl, C1-C8 alkyl, C1-C8 alkenyl, C1-C8 alkoxy, C1-C8 alkoxycarbonyl, aryloxycarbonyl, C2-C8 acyl, C2-C8 acylamino, C1-C8 alkylthio, arylalkylthio, arylthio, C1-C8 alkylsulfinyl, arylalkylsulfinyl, arylsulfinyl, C1-C8 alkylsulfonyl, arylalkylsulfonyl, arylsulfonyl, C0-C6 N-alkyl carbamoyl, C2-C15 N,N-dialkylcarbamoyl, C3-C7 cycloalkyl, aroyl, aryloxy, arylalkyl ether, aryl, aryl fused to a cycloalkyl or heterocycle or another aryl ring, C3-C7 heterocycle, C5-C15 heteroaryl or any of these rings fused or spiro-fused to a cycloalkyl, heterocyclyl, or aryl, wherein each of the foregoing is further optionally substituted with one more moieties listed in (a), above; and
        (c) —(CR32R33a)s—NR30R31, wherein s is from 0 (in which case the nitrogen is directly bonded to the moiety that is substituted) to 6, R32 and R33a are each independently hydrogen, halo, hydroxyl or C1-C4alkyl, and R30 and R31 are each independently hydrogen, cyano, oxo, hydroxyl, —C1-C8 alkyl, C1-C8 heteroalkyl, C1-C8 alkenyl, carboxamido, C1-C3 alkyl-carboxamido, carboxamido-C1-C3 alkyl, amidino, C2-C8hydroxyalkyl, C1-C3 alkylaryl, aryl-C1-C3 alkyl, C1-C3 alkylheteroaryl, heteroaryl-C1-C3 alkyl, C1-C3 alkylheterocyclyl, heterocyclyl-C1-C3 alkyl C1-C3 alkylcycloalkyl, cycloalkyl-C1-C3 alkyl, C2-C8 alkoxy, C2-C8 alkoxy-C1-C4alkyl, C1-C8 alkoxycarbonyl, aryloxycarbonyl, aryl-C1-C3 alkoxycarbonyl, heteroaryloxycarbonyl, heteroaryl-C1-C3 alkoxycarbonyl, C1-C8 acyl, C0-C8 alkyl-carbonyl, aryl-C0-C8 alkyl-carbonyl, heteroaryl-C0-C8 alkyl-carbonyl, cycloalkyl-C0-C8 alkyl-carbonyl, C0-C8 alkyl-NH-carbonyl, aryl-C0-C8 alkyl-NH-carbonyl, heteroaryl-C0-C8 alkyl-NH-carbonyl, cycloalkyl-C0-C8 alkyl-NH-carbonyl, C0-C8 alkyl-O-carbonyl, aryl-C0-C8 alkyl-O-carbonyl, heteroaryl-C0-C8 alkyl-O-carbonyl, cycloalkyl-C0-C8 alkyl-O-carbonyl, C1-C8 alkylsulfonyl, arylalkylsulfonyl, arylsulfonyl, heteroarylalkylsulfonyl, heteroarylsulfonyl, C1-C8 alkyl-NH-sulfonyl, arylalkyl-NH-sulfonyl, aryl-NH-sulfonyl, heteroarylalkyl-NH-sulfonyl, heteroaryl-NH-sulfonyl aroyl, aryl, cycloalkyl, heterocyclyl, heteroaryl, aryl-C1-C3 alkyl-, cycloalkyl-C1-C3 alkyl-, heterocyclyl-C1-C3 alkyl-, heteroaryl-C1-C3 alkyl-, or protecting group, wherein each of the foregoing is further optionally substituted with one more moieties listed in (a), above; or
    
    


R30 and R31 taken together with the N to which they are attached form a heterocyclyl or heteroaryl, each of which is optionally substituted with from 1 to 3 substituents selected from the group consisting of (a) above, a protecting group, and (X30—Y31—), wherein said heterocyclyl may also be bridged (forming a bicyclic moiety with a methylene, ethylene or propylene bridge); wherein
X30 is selected from the group consisting of C1-C8alkyl, C2-C8alkenyl-, C2-C8alkynyl-, —CO—C3alkyl-C2-C8alkenyl-C0-C3alkyl, C0-C3alkyl-C2-C8alkynyl-C0-C3alkyl, C0-C3alkyl-O—C0-C3alkyl-, HO—C0-C3alkyl-, C0-C4alkyl-N(R30)—C0-C3alkyl-, N(R30)(R31)—C0-C3alkyl-, N(R30)(R31)—C0-C3alkenyl-, N(R30)(R31)—C0-C3alkynyl-, (N(R30)(R31))2—C═N—, C0-C3alkyl-S(O)0-2—C0-C3alkyl-, CF3—C0-C3alkyl-, C1-C8heteroalkyl, aryl, cycloalkyl, heterocyclyl, heteroaryl, aryl-C1-C3alkyl-, cycloalkyl-C1-C3alkyl-, heterocyclyl-C1-C3alkyl-, heteroaryl-C1-C3alkyl-, N(R30)(R31)-heterocyclyl-C1-C3alkyl-, wherein the aryl, cycloalkyl, heteroaryl and heterocycyl are optionally substituted with from 1 to 3 substituents from (a); and Y31 is selected from the group consisting of a direct bond, —O—, —N(R30)—, —C(O)—, —O—C(O)—, —C(O)—O—, —N(R30)—C(O)—, —C(O)—N(R30)—, —N(R30)—C(S)—, —C(S)—N(R30)—, —N(R30)—C(O)—N(R31)—, —N(R30)—C(NR30)—N(R31)—, —N(R30)—C(NR31)—, —C(NR31)—N(R30), —N(R30)—C(S)—N(R31)—, —N(R30)—C(O)—O—, —O—C(O)—N(R31)—, —N(R30)—C(S)—O—, —O—C(S)—N(R3)—, —S(O)0-2—, —SO2N(R31)—, —N(R31)—SO2— and —N(R30)—SO2N(R31)—.
As a non-limiting example, substituted phenyls include 2-fluorophenyl, 3,4-dichlorophenyl, 3-chloro-4-fluoro-phenyl, 2-fluoro-3-propylphenyl. As another non-limiting example, substituted n-octyls include 2,4-dimethyl-5-ethyl-octyl and 3-cyclopentyl-octyl. Included within this definition are methylenes (—CH2—) substituted with oxygen to form carbonyl —CO—.
When there are two optional substituents bonded to adjacent atoms of a ring structure, such as for example phenyl, thiophenyl, or pyridinyl, the substituents, together with the atoms to which they are bonded, optionally form a 5- or 6-membered cycloalkyl or heterocycle having 1, 2, or 3 annular heteroatoms.
In a preferred embodiment, hydrocarbyl, alkyl, alkenyl, alkynyl, heteroalkyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aromatic polycycle, non-aromatic polycycle, polyheteroaryl, non-aromatic polyheterocyclic and mixed aryl and non-aryl polyheterocycle groups are unsubstituted.
In other preferred embodiments, hydrocarbyl, alkyl, alkenyl, alkynyl, heteroalkyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aromatic polycycle, non-aromatic polycycle, polyheteroaryl, non-aromatic polyheterocyclic and mixed aryl and non-aryl polyheterocycle groups are substituted with from 1 to 3 independently selected substituents.
Preferred substituents on alkyl groups include, but are not limited to, hydroxyl, halogen (e.g., a single halogen substituent or multiple halo substituents; in the latter case, groups such as CF3 or an alkyl group bearing more than one Cl), cyano, nitro, alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, heterocycle, aryl, —OR1, —SRu, —S(═O)Ry, —S(═O)2Ry, —P(═O)2Ry, —S(═O)2ORy, —P(═O)2ORy, —NRvRw, —NRvS(═O)2Ry, —NRvP(═O)2Ry, —S(═O)2NRvRw, —P(═O)2NRvRw, —C(═O)ORy, —C(═O)Ru, —C(═O)NRvRw, —OC(═O)Ru, OC(═O)NRvRw, NRvC(═O)ORy, —NRxxC(═O)NRvRw, —NRxxS(═O)2NRvRw, —NRxxP(═O)2NRvRw, —NRvC(═O)Ru or —NRvP(═O)2Ry, wherein Rw is hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, heterocycle or aryl; Rv, Rw and Rxx are independently hydrogen, alkyl, cycloalkyl, heterocycle or aryl, or said Rv and Rw together with the N to which they are bonded optionally form a heterocycle; and Ry is alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, heterocycle or aryl. In the aforementioned exemplary substituents, groups such as alkyl, cycloalkyl, alkenyl, alkynyl, cycloalkenyl, heterocycle and aryl can themselves be optionally substituted.
Preferred substituents on alkenyl and alkynyl groups include, but are not limited to, alkyl or substituted alkyl, as well as those groups recited as preferred alkyl substituents.
Preferred substituents on cycloalkyl groups include, but are not limited to, nitro, cyano, alkyl or substituted alkyl, as well as those groups recited about as preferred alkyl substituents. Other preferred substituents include, but are not limited to, spiro-attached or fused cyclic substituents, preferably spiro-attached cycloalkyl, spiro-attached cycloalkenyl, spiro-attached heterocycle (excluding heteroaryl), fused cycloalkyl, fused cycloalkenyl, fused heterocycle, or fused aryl, where the aforementioned cycloalkyl, cycloalkenyl, heterocycle and aryl substituents can themselves be optionally substituted.
Preferred substituents on cycloalkenyl groups include, but are not limited to, nitro, cyano, alkyl or substituted alkyl, as well as those groups recited as preferred alkyl substituents. Other preferred substituents include, but are not limited to, spiro-attached or fused cyclic substituents, especially spiro-attached cycloalkyl, spiro-attached cycloalkenyl, spiro-attached heterocycle (excluding heteroaryl), fused cycloalkyl, fused cycloalkenyl, fused heterocycle, or fused aryl, where the aforementioned cycloalkyl, cycloalkenyl, heterocycle and aryl substituents can themselves be optionally substituted.
Preferred substituents on aryl groups include, but are not limited to, nitro, cycloalkyl or substituted cycloalkyl, cycloalkenyl or substituted cycloalkenyl, cyano, alkyl or substituted alkyl, as well as those groups recited above as preferred alkyl substituents. Other preferred substituents include, but are not limited to, fused cyclic groups, especially fused cycloalkyl, fused cycloalkenyl, fused heterocycle, or fused aryl, where the aforementioned cycloalkyl, cylcoalkenyl, heterocycle and aryl substituents can themselves be optionally substituted. Still other preferred substituents on aryl groups (phenyl, as a non-limiting example) include, but are not limited to, haloalkyl and those groups recited as preferred alkyl substituents.
Preferred substituents on heterocylic groups include, but are not limited to, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, nitro, oxo (i.e., ═O), cyano, alkyl, substituted alkyl, as well as those groups recited as preferred alkyl substituents. Other preferred substituents on heterocyclic groups include, but are not limited to, spiro-attached or fused cylic substituents at any available point or points of attachement, more preferably spiro-attached cycloalkyl, spiro-attached cycloalkenyl, spiro-attached heterocycle (excluding heteroaryl), fused cycloalkyl, fused cycloakenyl, fused heterocycle and fused aryl, where the aforementioned cycloalkyl, cycloalkenyl, heterocycle and aryl substituents can themselves be optionally substituted.
In a preferred embodiment, a heterocyclic group is substituted on carbon, nitrogen and/or sulfur at one or more positions. Preferred substituents on nitrogen include, but are not limited to N-oxide, alkyl, aryl, aralkyl, alkylcarbonyl, alkylsulfonyl, arylcarbonyl, arylsulfonyl, alkoxycarbonyl, or aralkoxycarbonyl. Preferred substituents on sulfur include, but are not limited to, oxo and C1-6alkyl. In certain preferred embodiments, nitrogen and sulfur heteroatoms may independently be optionally oxidized and nitrogen heteroatoms may independently be optionally quaternized.
Especially preferred substituents on alkyl groups include halogen and hydroxy.
Especially preferred substituents on ring groups, such as aryl, heteroaryl, cycloalkyl and heterocyclyl, include halogen, alkoxy and alkyl.
Preferred substituents on aromatic polycycles include, but are not limited to, oxo, C1-C6alkyl, cycloalkylalkyl (e.g. cyclopropylmethyl), oxyalkyl, halo, nitro, amino, alkylamino, aminoalkyl, alkyl ketones, nitrile, carboxyalkyl, alkylsulfonyl, arylsulfonyl, aminosulfonyl and ORaa, such as alkoxy, wherein Raa is selected from the group consisting of H, C1-C6alkyl, C4-C9cycloalkyl, C4-C9heterocycloalkyl, aryl, heteroaryl, arylalkyl, heteroarylalkyl and (CH2)0-6ZaRbb, wherein Za is selected from the group consisting of O, NRcc, S and S(O), and Rbb is selected from the group consisting of H, C1-C6alkyl, C4-C9cycloalkyl, C4-C9heterocycloalkyl, C4-C9heterocycloalkylalkyl, aryl, mixed aryl and non-aryl polycycle, heteroaryl, arylalkyl, (e.g. benzyl), and heteroarylalkyl (e.g. pyridylmethyl); and Rcc is selected from the group consisting of H, C1-C6alkyl, C4-C9cycloalkyl, C4-C9heterocycloalkyl, aryl, heteroaryl, arylalkyl (e.g. benzyl), heteroarylalkyl (e.g. pyridylmethyl) and amino acyl.
Preferred substituents on non-aromatic polycycles include, but are not limited to, oxo, C3-C9cycloalkyl, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. Unless otherwise noted, non-aromatic polycycle substituents include both unsubstituted cycloalkyl groups and cycloalkyl groups that are substituted by one or more suitable substituents, including but not limited to, C1-C6alkyl, oxo, halo, hydroxy, aminoalkyl, oxyalkyl, alkylamino and ORaa, such as alkoxy. Preferred substituents for such cycloalkyl groups include halo, hydroxy, alkoxy, oxyalkyl, alkylamino and aminoalkyl.
Preferred substituents on carbon atoms of polyheteroaryl groups include but are not limited to, straight and branched optionally substituted C1-C6alkyl, unsaturation (i.e., there are one or more double or triple C—C bonds), acyl, oxo, cycloalkyl, halo, oxyalkyl, alkylamino, aminoalkyl, acylamino, ORaa (for example alkoxy), and a substituent of the formula —O—(CH2CH═CH(CH3)(CH2))1-3H. Examples of suitable straight and branched C1-C6alkyl substituents include but are not limited to methyl, ethyl, n-propyl, 2-propyl, n-butyl, sec-butyl, t-butyl and the like. Preferred substituents include halo, hydroxy, alkoxy, oxyalkyl, alkylamino and aminoalkyl. Preferably substitutions on nitrogen atoms include, for example by N-oxide or Rcc. Preferred substituents on nitrogen atoms include H, C1-C4alkyl, acyl, aminoacyl and sulfonyl. Preferably sulfur atoms are unsubstituted. Preferred substituents on sulfur atoms include but are not limited to oxo and lower alkyl.
Preferred substituents on carbon atoms of non-aromatic polyheterocyclic groups include but are not limited to straight and branched optionally substituted C1-C6alkyl, unsaturation (i.e., there are one or more double or triple C—C bonds), acyl, oxo, cycloalkyl, halo, oxyalkyl, alkylamino, aminoalkyl, acylamino and ORaa, for example alkoxy. Examples of suitable straight and branched C1-C6alkyl substituents include but are not limited to methyl, ethyl, n-propyl, 2-propyl, n-butyl, sec-butyl, t-butyl and the like. Preferred substituents include halo, hydroxy, alkoxy, oxyalkyl, alkylamino and aminoalkyl. Preferably substitutions on nitrogen atoms include, for example, N-oxide or Rcc. Preferred N substituents include H, C1-C4 alkyl, acyl, aminoacyl and sulfonyl. Preferably, sulfur atoms are unsubstituted. Preferred S substituents include oxo and lower alkyl.
Preferred substituents on mixed aryl and non-aryl polyheterocycle groups include, but are not limited to, nitro or as described above for non-aromatic polycycle groups. Preferred substituents on carbon atoms include, but are not limited to, —N—OH, ═N—OH, optionally substituted alkyl, unsaturation (i.e., there are one or more double or triple C—C bonds), oxo, acyl, cycloalkyl, halo, oxyalkyl, alkylamino, aminoalkyl, acylamino and ORaa, for example alkoxy. Preferably substitutions on nitrogen atoms include, for example, N-oxide or Rcc. Preferred N substituents include H, C1-4alkyl, acyl aminoacyl and sulfonyl. Preferably sulfur atoms are unsubstituted. Preferred S substituents include oxo and lower alkyl.
A “halohydrocarbyl” is a hydrocarbyl moiety in which from one to all hydrogens have been replaced with one or more halo.
The term “halogen” or “halo” is intended to mean chlorine, bromine, fluorine, or iodine. As herein employed, the term “acyl” refers to an alkylcarbonyl or arylcarbonyl substituent. The term “acylamino” refers to an amide group attached at the nitrogen atom (i.e., R—CO—NH—). The term “carbamoyl” refers to an amide group attached at the carbonyl carbon atom (i.e., NH2—CO—). The nitrogen atom of an acylamino or carbamoyl substituent is additionally optionally substituted. The term “sulfonamido” refers to a sulfonamide substituent attached by either the sulfur or the nitrogen atom. The term “amino” is meant to include NH2, alkylamino, arylamino, and cyclic amino groups. The term “ureido” as employed herein refers to a substituted or unsubstituted urea moiety.
The term “radical” is intended to mean a chemical moiety comprising one or more unpaired electrons.
Where optional substituents are chosen from “one or more” groups it is to be understood that this definition includes all substituents being chosen from one of the specified groups or the substituents being chosen from two or more of the specified groups.
In addition, substituents on cyclic moieties (i.e., cycloalkyl, heterocyclyl, aryl, heteroaryl) include 5-6 membered mono- and 9-14 membered bi-cyclic moieties fused to the parent cyclic moiety to form a bi- or tri-cyclic fused ring system. Substituents on cyclic moieties also include 5-6 membered mono- and 9-14 membered bi-cyclic moieties attached to the parent cyclic moiety by a covalent bond to form a bi- or tri-cyclic bi-ring system. For example, an optionally substituted phenyl includes, but is not limited to, the following:




An “unsubstituted” moiety (e.g., unsubstituted cycloalkyl, unsubstituted heteroaryl, etc.) means that moiety as defined above that does not have an optional substituent. Thus, for example, “unsubstituted aryl” does not include phenyl substituted with a halo.
As used herein, “an amino protecting group” refers to any functional group commonly used to protect an α-amino group. Suitable amino protecting groups include, but are not limited to, t-butyloxycarbonyl, isoamyloxycarbonyl, o-nitrophenylsulfenyl, fluoroenylmethyloxycarbonyl, o-nitropyridinylsulfenyl and biphenylpropyloxycarbonyl.
An “amino acid residue” refers to any residue of a natural or unnatural amino acid, non-limiting examples of which are residues of alanine, arginine, asparagine, aspartic acid, cysteine, homocysteine, glutamine, glutamic acid, isoleucine, norleucine, glycine, phenylglycine, leucine, histidine, methionine, lysine, phenylalanine, homophenylalanine, ornithine, praline, serine, homoserine, valine, norvaline, threonine, tryptophane, tyrosine and the like. With the exception of glycine, all amino acids may be in the D-, L- or D,L-form.
The term “radical” is intended to mean a chemical moiety comprising one or more unpaired electrons.
Some compounds of the invention may have one or more chiral centers and/or geometric isomeric centers (E- and Z-isomers), and it is to be understood that the invention encompasses all such optical, diastereoisomers and geometric isomers. The invention also comprises all tautomeric forms of the compounds disclosed herein.
All of the compounds in this application were named using Chemdraw Ultra version 9 or 10, which are available through Cambridgesoft.co, 100 Cambridge Park Drive, Cambridge, Mass. 02140.
Compounds
In a first aspect, the invention provides prodrugs of inhibitors of histone deacetylase, the prodrugs having the formula (1):

Cy-L1-Ar—Y1—C(O)—N(Rx)—Z  (1)

and pharmaceutically acceptable salts thereof, wherein
Cy is —H, cycloalkyl, aryl, heteroaryl, or heterocyclyl, any of which may be optionally substituted;
L1 is —(CH2)m—W—, where m is 0, 1, 2, 3, or 4, and W is selected from the group consisting of —C(O)NH—, —S(O)2NH—, —NHC(O)—, —NHS(O)2—, and —NH—C(O)—NH—;
Ar is arylene, wherein said arylene optionally may be additionally substituted and optionally may be fused to an aryl or heteroaryl ring, or to a saturated or partially unsaturated cycloalkyl or heterocyclic ring, any of which may be optionally substituted;
Y1 is a chemical bond or a straight- or branched-chain saturated alkylene, wherein said alkylene may be optionally substituted;
Rx is H or —OH;

    Z is —R20, —O—R20, —R21, or






     wherein —R20 is selected from the group consisting of —C(O)—R10, —C(O)O—R10, —R10, —CH(R12)—O—C(O)—R10, —C(O)—C[(R10)(R10′)]1-4—NH(R13), —S(O2)R10, —P(O)(OR10)(OR10), —C(O)—(CH2)n—CH(OH)—CH2—O—R10, —C(O)—(CH2)1-4—C(OH)(COOR10)—(CH2)1-4—COOR10, —C(O)-[C(R14)(R14)]1-4—P(O)(OH)(OH), —C(O)—(CH2)1-4—N(R14)—C[═N(R10′)]-N(R10′)(R10′), —C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —C(O)—CH(NH2)—(CH2)1-6—COOH (preferably —C(O)—CH(NH2)—(CH2)—COOH), —C(O)—O—(CH2)n—CH(OH)—CH2—O—R10 and —C(O)—(CH2)n—C(O)OR10, provided that the N to which Z is bound is not directly bonded to two O atoms and further provided that (a) when Z is —R20 then Rx is —OH, and (b) when Z is —OR20 then Rx is —H; or


Rx is absent and R20 forms an optionally substituted heterocyclic ring with the N to which it is attached;
n is 0, 1, 2, 3, or 4, preferably 1, 2, 3, or 4;
each R10 is independently selected from the group consisting of hydrogen, optionally substituted C1-C20 alkyl, optionally substituted C2-C20 alkenyl, optionally substituted C2-C20 alkynyl, optionally substituted C1-C20 alkoxycarbonyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkylalkyl, optionally substituted heterocycloalkylalkyl, optionally substituted arylalkyl, optionally substituted heteroarylalkyl, optionally substituted cycloalkylalkenyl, optionally substituted heterocycloalkylalkenyl, optionally substituted arylalkenyl, optionally substituted heteroarylalkenyl, optionally substituted cycloalkylalkynyl, optionally substituted heterocycloalkylalkynyl, optionally substituted arylalkynyl, optionally substituted heteroarylalkynyl, optionally substituted alkylcycloalkyl, optionally substituted alkylheterocycloalkyl, optionally substituted alkylaryl, optionally substituted alkylheteroaryl, optionally substituted alkenylcycloalkyl, optionally substituted alkenylheterocycloalkyl, optionally substituted alkenylaryl, optionally substituted alkenylheteroaryl, optionally substituted alkynylcycloalkyl, optionally substituted alkynylheterocycloalkyl, optionally substituted alkynylary, optionally substituted alkynylheteroaryl, a sugar residue, and an amino acid residue (preferably bonded through the carboxy terminus of the amino acid);
each R10′ is independently hydrogen or C1-6alkyl, or
R10 and R10′ together with the carbon atom to which they are attached form an optionally substituted spirocycloalkyl;
R21 is a sugar or -amino acid-R13, wherein R13 is covalently bound to the N-terminus;
R11 is selected from the group consisting of hydrogen, optionally substituted heterocycloalkyl, optionally substituted aryl, and optionally substituted heteroaryl;
R12 is selected from hydrogen or alkyl; and
R13 is selected from the group consisting of hydrogen, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-N(R10′)(R10′), —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-aryl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-heteroaryl, —C(O)-aryl, —C(O)-heteroaryl, an amino protecting group, and R10; and
each R14 is independently selected from the group consisting of H, C1-C6alkyl and cycloalkyl, or two R14, together with the atom to which they are attached, form a cycloalkyl.
In certain preferred embodiments, Cy is C6-C14 aryl, more preferably C6-C10 aryl, and most preferably phenyl or naphthyl, any of which may be optionally substituted. In certain other preferred embodiments, Cy is heteroaryl. In some preferred embodiments, the heteroaryl group is selected from the group consisting of thienyl, benzothienyl, furyl, benzofuryl, quinolyl, isoquinolyl, and thiazolyl, any of which may be optionally substituted. In certain particularly preferred embodiments, Cy is selected from the group consisting of phenyl, naphthyl, thienyl, benzothienyl, and quinolyl, any of which may be optionally substituted. In certain other preferred embodiments, Cy is phenyl, pyridine or indole, more preferably phenyl or indole. In certain preferred embodiments, Cy is substituted with one or more substituents selected from the group consisting of trihaloalkyl (preferably trifluoroalkyl), halogen, CN, amidine, sulfone, alkylsulfone, imidate and alkylimidate. In certain preferred embodiments, Cy is phenyl substituted with one or more substituents selected from the group consisting of trihaloalkyl (preferably trifluoroalkyl), halogen, CN, amidine, sulfone, alkylsulfone, imidate and alkylimidate, preferably selected from the group consisting of trihaloalkyl (preferably trifluoroalkyl) and halogen.
L1 is —(CH2)m—W—, where m is 0, 1, 2, 3, or 4, and W is selected from the group consisting of —C(O)NH—, —S(O)2NH—, —NHC(O)—, —NHS(O)2—, and —NH—C(O)—NH—. Preferably, m is 0, 1, or 2, more preferably 0 or 1.
Preferably, Ar is C6-C14 arylene, more preferably C6-C10 arylene, any of which may be additionally substituted. In certain preferred embodiments, Ar is phenylene, preferably 4-phenylene. In some preferred embodiments, the phenylene is fused to an aryl or heteroaryl ring, or to a saturated or partially unsaturated cycloalkyl or heterocyclic ring, any of which groups also may be optionally substituted.
Y1 is a chemical bond or is a straight- or branched-chain alkylene, which may be optionally substituted. In some preferred embodiments, Y1 is a chemical bond, and the group —C(O)NH-Z is directly attached to Ar. In some other preferred embodiments, Y1 is alkylene, preferably saturated alkylene. Preferably, the saturated alkylene is C1-C8 alkylene, more preferably C1-C6 alkylene, still more preferably C1-C3 alkylene, and yet still more preferably C1-C2 alkylene, any of which may be optionally substituted. In some particularly preferred embodiments, Y1 is methylene.
Substituted alkyl, aryl, heterocyclyl, and heteroaryl groups have one or more, preferably between one and about three, more preferably one or two substituents, which are preferably selected from the group consisting of C1-C6 alkyl, preferably C1-C4 alkyl; halo, preferably Cl, Br, or F; haloalkyl, preferably (halo)1-5(C1-C6)alkyl, more preferably (halo)1-5(C1-C3)alkyl, and most preferably CF3; C1-C6 alkoxy, preferably methoxy, ethoxy, or benzyloxy; C6-C10 aryloxy, preferably phenoxy; C1-C6 alkoxycarbonyl, preferably C1-C3 alkoxycarbonyl, most preferably carbomethoxy or carboethoxy; C6-C10 aryl, preferably phenyl; (C6-C10)ar(C1-C6)alkyl, preferably (C6-C10)ar(C1-C3)alkyl, more preferably benzyl, naphthylmethyl or phenethyl; hydroxy(C1-C6)alkyl, preferably hydroxy(C1-C3)alkyl, more preferably hydroxymethyl; amino(C1-C6)alkyl, preferably amino(C1-C3)alkyl, more preferably aminomethyl; (C1-C6)alkylamino, preferably methylamino, ethylamino, or propylamino; di-(C1-C6)alkylamino, preferably dimethylamino or diethylamino; (C1-C6)alkylcarbamoyl, preferably methylcarbamoyl, dimethylcarbamoyl, or benzylcarbamoyl; (C6-C10)arylcarbamoyl, preferably phenylcarbamoyl; (C1-C6)alkaneacylamino, preferably acetylamino; (C6-C10)areneacylamino, preferably benzoylamino; (C1-C6)alkanesulfonyl, preferably methanesulfonyl; (C1-C6)alkanesulfonamido, preferably methanesulfonamido; (C6-C10)arenesulfonyl, preferably benzenesulfonyl or toluenesulfonyl; (C6-C10)arenesulfonamido, preferably benzenesulfonyl or toluenesulfonyl; (C6-C10)ar(C1-C6)alkylsulfonamido, preferably benzylsulfonamido; C1-C6 alkylcarbonyl, preferably C1-C3 alkylcarbonyl, more preferably acetyl; (C1-C6)acyloxy, preferably acetoxy; cyano; amino; carboxy; hydroxy; ureido; and nitro. One or more carbon atoms of an alkyl, cycloalkyl, or heterocyclyl group may also be optionally substituted with an oxo group.
In some particularly preferred embodiments, Cy is a phenyl, naphthyl, thienyl, benzothienyl, or quinolyl moiety which is unsubstituted or is substituted by one or two substituents independently selected from the group consisting of C1-C4 alkyl, C1-C4 haloalkyl, C6-C10 aryl, (C6-C10)ar(C1-C6)alkyl, halo, nitro, hydroxy, C1-C6 alkoxy, C1-C6 alkoxycarbonyl, carboxy, and amino.
In some preferred embodiments, Z is —O—C(O)—R10, —O—C(O)-[C(R10)(R10′)]1-4—NH(R13) or —OR11.
In some preferred embodiments, the amino acid is an L-amino acid.
In certain preferred embodiments, the sugar residue is a saccharide selected from the group consisting of glucose, galactose, mannose, gulose, idose, talose, allose, altrose, fructose, rhamnose, ribose and xylose.
In a second embodiment, the invention provides prodrugs of inhibitors of histone deacetylase, the prodrugs represented by formula (2):

Cy-L2-Ar—Y2—C(O)N(Rx)—Z  (2)

and pharmaceutically acceptable salts thereof, wherein
Cy is H, cycloalkyl, aryl, heteroaryl, or heterocyclyl, any of which may be optionally substituted, provided that Cy is not a (spirocycloalkyl)heterocyclyl;
L2 is C1-C6 saturated alkylene or C2-C6 alkenylene, wherein the alkylene or alkenylene optionally may be substituted, and wherein one or two of the carbon atoms of the alkylene is optionally replaced by a heteroatomic moiety independently selected from the group consisting of O; NR′, R′ being alkyl, acyl, or hydrogen; S; S(O); or S(O)2;
Ar is arylene, wherein said arylene optionally may be additionally substituted and optionally may be fused to an aryl or heteroaryl ring, or to a saturated or partially unsaturated cycloalkyl or heterocyclic ring, any of which may be optionally substituted; and
Y2 is a chemical bond or a straight- or branched-chain saturated alkylene, which may be optionally substituted, provided that the alkylene is not substituted with a substituent of the formula —C(O)R wherein R comprises an α-amino acyl moiety;
Rx is H or —OH;
Z is —R20, —O—R20, —R21, or




wherein —R20 is selected from the group consisting of —C(O)—R10, —C(O)O—R11, —R10, —CH(R12)—O—C(O)—R10, —C(O)—C[(R10)(R10′)]1-4—NH(R13), —S(O2)R10, —P(O)(OR10)(OR10), —C(O)—(CH2)14—C(OH)(COOR10)—(CH2)1-4—COOR10, —C(O)-[C(R14)(R14)]1-4—P(O)(OH)(OH), —C(O)—(CH2)1-4—N(R14)—C[═N(R10′)]-N(R10′)(R10′), —C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —C(O)—CH(NH2)—(CH2)1-6—COOH (preferably —C(O)—CH(NH2)—(CH2)—COOH), —C(O)—(CH2)n—CH(OH)—CH2—O—R10, —C(O)—O—(CH2)n—CH(OH)—CH2—O—R10 and —C(O)—(CH2)n—C(O)OR10, provided that the N to which Z is bound is not directly bonded to two O atoms; and further provided that (a) when Z is —R20 then Rx is —OH, and (b) when Z is —OR20 then Rx is —H; or

Rx is absent and R20 forms an optionally substituted heterocyclic ring with the N to which it is attached;
n is 0, 1, 2, 3, or 4, preferably 1, 2, 3, or 4;
each R10 is independently selected from the group consisting of hydrogen, optionally substituted C1-C20 alkyl, optionally substituted C2-C20 alkenyl, optionally substituted C2-C20 alkynyl, optionally substituted C1-C20 alkoxycarbonyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkylalkyl, optionally substituted heterocycloalkylalkyl, optionally substituted arylalkyl, optionally substituted heteroarylalkyl, optionally substituted cycloalkylalkenyl, optionally substituted heterocycloalkylalkenyl, optionally substituted arylalkenyl, optionally substituted heteroarylalkenyl, optionally substituted cycloalkylalkynyl, optionally substituted heterocycloalkylalkynyl, optionally substituted arylalkynyl, optionally substituted heteroarylalkynyl, optionally substituted alkylcycloalkyl, optionally substituted alkylheterocycloalkyl, optionally substituted alkylaryl, optionally substituted alkylheteroaryl, optionally substituted alkenylcycloalkyl, optionally substituted alkenylheterocycloalkyl, optionally substituted alkenylaryl, optionally substituted alkenylheteroaryl, optionally substituted alkynylcycloalkyl, optionally substituted alkynylheterocycloalkyl, optionally substituted alkynylary, optionally substituted alkynylheteroaryl, a sugar residue, and an amino acid residue (preferably bonded through the carboxy terminus of the amino acid);
each R10′ is independently hydrogen or C1-6alkyl, or
R10 and R10′ together with the carbon atom to which they are attached form an optionally substituted spirocycloalkyl;
R21 is a sugar or -amino acid-R3, wherein R13 is covalently bound to the N-terminus;
R11 is selected from the group consisting of hydrogen, optionally substituted heterocycloalkyl, optionally substituted aryl, and optionally substituted heteroaryl;
R12 is selected from hydrogen or alkyl; and
R13 is selected from the group consisting of hydrogen, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-N(R10′)(R10′), —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-aryl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-heteroaryl, —C(O)-aryl, —C(O)-heteroaryl, an amino protecting group, and R10; and
each R14 is independently selected from the group consisting of H, C1-C6alkyl and cycloalkyl, or two R together with the atom to which they are attached, form a cycloalkyl.
Preferred substituents Cy, Ar, and Z according to this aspect of the invention are as defined above for the first embodiment. Preferred substituents of Y2 are as defined above for Y1. In some preferred embodiments, L2 is saturated C1-C8 alkylene, more preferably C1-C6 alkylene, still more preferably C1-C4 alkylene, any of which groups may be optionally substituted. In some other preferred embodiments, L2 is C2-C8 alkenylene, more preferably C2-C6 alkenylene, and still more preferably C2-C4 alkenylene, any of which groups may be optionally substituted. The alkylene or alkenylene group may be substituted at one or more carbon positions with a substituent preferably selected from the list of preferred substituents recited above. More preferably, L2 is substituted at one or two positions with a substituent independently selected from the group consisting of C1-C6 alkyl, C6-C10 aryl, amino, oxo, hydroxy, C1-C4 alkoxy, and C6-C10 aryloxy. In some particularly preferred embodiments, the alkylene or alkenylene group is substituted with one or two oxo or hydroxy groups.
In some preferred embodiments, L1 is C1-C6 saturated alkylene, wherein on of the carbon atoms of the saturated alkylene is replaced by a heteroatom moiety selected from the group consisting of O; NR′, R′ being alkyl, acyl, or hydrogen; S; S(O); or S(O)2. Preferably, the carbon atom adjacent to Cy is replaced by a heteroatom moiety. In some particularly preferred embodiments, L1 is selected from the group consisting of —S—(CH2)2—, —S(O)—(CH2)2—, —S(O)2—(CH2)2—, —S—(CH2)3—, —S(O)—(CH2)3—, and —S(O)2—(CH2)3—.
In some preferred embodiments, Z is —O—C(O)—R10, —O—C(O)-[C(R10)(R10′)]1-4—NH(R13) or —OR11. Even more preferred embodiments of compound (2) are:




In a third embodiment, the invention provides prodrugs of inhibitors of histone deacetylase, the prodrugs represented by formula (3):

Cy-L3-Ar—Y3—C(O)N(Rx)—Z  (3)

and pharmaceutically acceptable salts thereof, wherein

Cy is —H, cycloalkyl, aryl, heteroaryl, or heterocyclyl, any of which may be optionally substituted, provided that Cy is not a (spirocycloalkyl)heterocyclyl;
L3 is selected from the group consisting of
(a) —(CH2)m—W—, where m is 0, 1, 2, 3, or 4, and W is selected from the group consisting of —C(O)NH—, —S(O)2NH—, —NHC(O)—, —NHS(O)2—, and —NH—C(O)—NH—; and
(b) C1-C6 alkylene or C2-C6 alkenylene, wherein the alkylene or alkenylene optionally may be substituted, and wherein one of the carbon atoms of the alkylene optionally may be replaced by O; NR′, R′ being alkyl, acyl, or hydrogen; S; S(O); or S(O)2;
Ar is arylene, wherein said arylene optionally may be additionally substituted and optionally may be fused to an aryl or heteroaryl ring, or to a saturated or partially unsaturated cycloalkyl or heterocyclic ring, any of which may be optionally substituted; and
Y3 is C2 alkenylene or C2 alkynylene, wherein one or both carbon atoms of the alkenylene optionally may be substituted with alkyl, aryl, alkaryl, or aralkyl;
Rx is H or —OH;
Z is —R20, —O—R20, —R21, or




wherein —R20 is selected from the group consisting of —C(O)—R10, —C(O)O—R10, —R10, —CH(R12)—O—C(O)—R10, —C(O)—(CH2)14—C(OH)(COOR10)—(CH2)1-4—COOR10, —C(O)-[C(R14)(R14)]1-4—P(O)(OH)(OH), —C(O)—(CH2)14—N(R14)—C[═N(R10′)]-N(R10′)(R10′), —C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —C(O)—CH(NH2)—(CH2)1-6—COOH (preferably —C(O)—CH(NH2)—(CH2)—COOH), —C(O)—C[(R10)(R10′)]1-4—NH(R13), —S(O2)R10, —P(O)(OR10)(OR10), —C(O)—(CH2)n—CH(OH)—CH2—O—R10, —C(O)—O—(CH2)n—CH(OH)—CH2—O—R10 and —C(O)—(CH2)n—C(O)OR10, provided that the N to which Z is bound is not directly bonded to two O atoms; and further provided that (a) when Z is —R20 then Rx is —OH, and (b) when Z is —OR20 then Rx is —H; or

Rx is absent and R20 forms an optionally substituted heterocyclic ring with the N to which it is attached;
n is 0, 1, 2, 3, or 4, preferably 1, 2, 3, or 4;
each R10 is independently selected from the group consisting of hydrogen, optionally substituted C1-C20 alkyl, optionally substituted C2-C20 alkenyl, optionally substituted C2-C20 alkynyl, optionally substituted C1-C20 alkoxycarbonyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkylalkyl, optionally substituted heterocycloalkylalkyl, optionally substituted arylalkyl, optionally substituted heteroarylalkyl, optionally substituted cycloalkylalkenyl, optionally substituted heterocycloalkylalkenyl, optionally substituted arylalkenyl, optionally substituted heteroarylalkenyl, optionally substituted cycloalkylalkynyl, optionally substituted heterocycloalkylalkynyl, optionally substituted arylalkynl, optionally substituted heteroarylalkynyl, optionally substituted alkylcycloalkyl, optionally substituted alkylheterocycloalkyl, optionally substituted alkylaryl, optionally substituted alkylheteroaryl, optionally substituted alkenylcycloalkyl, optionally substituted alkenylheterocycloalkyl, optionally substituted alkenylaryl, optionally substituted alkenylheteroaryl, optionally substituted alkynylcycloalkyl, optionally substituted alkynylheterocycloalkyl, optionally substituted alkynylary, optionally substituted alkynylheteroaryl, a sugar residue, and an amino acid residue (preferably bonded through the carboxy terminus of the amino acid);
each R10′ is independently hydrogen or C1-6alkyl, or
R10 and R10′ together with the carbon atom to which they are attached form an optionally substituted spirocycloalkyl;
R21 is a sugar or -amino acid-R13, wherein R13 is covalently bound to the N-terminus;
R11 is selected from the group consisting of hydrogen, optionally substituted heterocycloalkyl, optionally substituted aryl, and optionally substituted heteroaryl;
R12 is selected from hydrogen or alkyl; and
R13 is selected from the group consisting of hydrogen, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-N(R10′)(R10′), —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-aryl, —C(O)—CH[N(R10′)(R10′)]-C1-C6alkyl-heteroaryl, —C(O)-aryl, —C(O)-heteroaryl, an amino protecting group, and R10; and
each R14 is independently selected from the group consisting of H, C1-C6alkyl and cycloalkyl, or two R together with the atom to which they are attached, form a cycloalkyl.
Preferred substituents Cy, Ar, and Z according to this aspect of the invention are as defined above for the first embodiment. Preferred substituents L3 are as defined above for L1 or L2 
Preferably, Y3 is C2 alkenylene or C2 alkynylene, wherein one or both carbon atoms of the alkenylene optionally may be substituted with C1-C6 alkyl, C6-C10 aryl, (C1-C6)alk(C6-C10)aryl, or (C6-C10)ar(C1-C6)alkyl. More preferably, Y3 is C2 alkenylene or C2 alkynylene, wherein one or both carbon atoms of the alkenylene optionally may be substituted with C1-C4 alkyl, C6-C10 aryl, (C1-C4)alk(C6-C10)aryl, or (C6-C10)ar(C1-C4)alkyl. Still more preferably, Y3 is selected from the group consisting of —C≡C—, —CH═CH—, —C(CH3)═CH—, and —CH═C(CH3)—.
In a preferred embodiment of the compounds of formulae (1), (2), and (3), Z is selected from the group consisting of —O—C(O)—(CH2)1-4—C(OH)(COOR10)—(CH2)1-4—COOR10, —O—C(O)-[C(R14)(R14)]1-4—P(O)(OH)(OH), —O—C(O)—(CH2)1-4—N(R14)—C [═N(R10′)]-N(R10′)(R10′), —O—C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —O—C(O)—CH(NH2)—(CH2)1-6—COOH, preferably —O—C(O)—CH(NH2)—(CH2)—COOH.
In a preferred embodiment of the compounds of formulae (1), (2), and (3), Z is selected from the group consisting of —O—C(O)—(CH2)—C(OH)(COOH)—(CH2)—COOH, —O—C(O)—CH2—P(O)(OH)(OH), —O—C(O)—(CH2)—N(CH3)—C(═NH)—NH2, —O—C(O)—(CH2)—CH(OH)—(CH2)—N(CH3)(CH3), —O—C(O)—CH(NH2)—(CH2)—COOH.
In some preferred embodiments, Z is —O—C(O)—R10, —O—C(O)-[C(R10)(R10′)]1-4—NH(R13) or —OR11.
In some preferred embodiments of the prodrugs of inhibitors of histone deacetylase, of formulae (1), (2), and (3), Z is —O—R20 wherein R20 is —C(O)—CR10R10′—NH(R13), R13 and R10′ are H, and R10 is C1-C6-alkyl or an amino acid side chain, or R10 and R10′ together with the carbon to which they are linked form C3-C6 cycloalkyl.
Naturally-occurring or non-naturally occurring amino acids are used to prepare the prodrugs of the invention. In particular, standard amino acids suitable as a prodrug moiety include valine, leucine, isoleucine, methionine, phenylalanine, asparagine, glutamic acid, glutamine, histidine, lysine, arginine, aspartic acid, glycine, alanine, serine, threonine, tyrosine, tryptophan, cysteine and proline. Particularly preferred are L-amino acids. Optionally an included amino acid is an α-, β-, or γ-amino acid. Also, naturally-occurring, non-standard amino acids can be utilized in the compositions and methods of the invention. For example, in addition to the standard naturally occurring amino acids commonly found in proteins, naturally occurring amino acids also illustratively include 4-hydroxyproline, gamma.-carboxyglutamic acid, selenocysteine, desmosine, 6-N-methyllysine, epsilon.-N,N,N-trimethyllysine, 3-methylhistidine, O-phosphoserine, 5-hydroxylysine, epsilon.-N-acetyllysine, omega.-N-methylarginine, N-acetylserine, gamma.-aminobutyric acid, citrulline, ornithine, azaserine, homocysteine, beta.-cyanoalanine and S-adenosylmethionine. Non-naturally occurring amino acids include phenyl glycine, meta-tyrosine, para-amino phenylalanine, 3-(3-pyridyl)-L-alanine-, 4-(trifluoromethyl)-D-phenylalanine, and the like.
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except that R20 of Z is described in U.S. Pat. No. 4,443,435 (incorporated by reference in its entirety) as comprising —CH(R130)—X—C(O)—R131 wherein
X is O, S, or NR132;
R131 is

    
    
        (a) straight or branched chain alkyl having from 1 to 20 carbon atoms especially methyl, ethyl, isopropyl, t-butyl, pentyl or hexyl;
        (b) aryl having from 6 to 10 carbon atoms especially phenyl, substituted pentyl or naphthalene;
        (c) cycloalkyl having from 3 to 8 carbon atoms especially cyclopentyl, or cyclohexyl;
        (d) alkenyl having from 2-20 carbon atoms especially C2-6 alkenyl such as vinyl, allyl, or butenyl;
        (e) cycloalkenyl having from 5 to 8 carbon atoms especially cyclopentenyl or cyclohexenyl;
        (f) alkynyl having from 2 to 20 carbon atoms especially C2-6 alkynyl for example, ethynyl, propynyl or hexynyl;
        (g) aralkyl, alkaryl, aralkenyl, aralkynyl, alkenylaryl or alkynylaryl wherein alkyl, aryl, alkenyl and alkynyl are as previously defined;
        (h) lower alkoxycarbonyl especially C1-6 alkoxycarbonyl such as methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl and cyclopentoxycarbonyl;
        (i) carboxyalkyl or alkanoyloxyalkyl especially carboxy-C1-6 alkyl such as formyloxymethyl and formyloxypropyl; or C1-6 (alkylcarboxyalkyl) such as acetoxymethyl, n-propanoyloxyethyl and pentanoyloxybutyl;
        (j) saturated or unsaturated monoheterocyclic or polyheterocyclic, or fused heterocyclic, either directly bonded to the carbonyl function or linked thereto via an alkylene bridge, containing from 1 to 3 of any one or more of the heteroatoms N, S or O in each heterocyclic ring thereof and each such ring being from 3- to 8-membered; and
        (k) mono- or polysubstituted derivatives of the above, each of said substituents being selected from the group consisting of lower alkyl; lower alkoxy; lower alkanoyl; lower alkanoyloxy; halo especially bromo, chloro, or fluoro; haloloweralkyl especially fluoro, chloro or bromoloweralkyl such as trifluoromethyl and 1-chloropropyl; cyano; carbethoxy; loweralkylthio, especially C1-6 loweralkylthio such as methylthio, ethylthio and n-propylthio; nitro; carboxyl; amino; loweralkylamino especially C1-6 alkylamino, for example, methylamino, ethylamino and n-butylamino; diloweralkylamino especially di(C1-6 loweralkyl)amino such as N,N-dimethylamino, N,N-diethylamino and N,N-dihexylamino; carbamyl; loweralkylcarbamyl especially C1-6 alkylcarbamyl such as methylcarbamyl and ethyl carbamoyl; and R133—X—C(O)-phenyl-, wherein R133 is hydrogen or alkyl having from 1 to 10 carbons;
    
    


R130 is hydrogen, (b) R131, lower alkanoyl, cyano, haloloweralkyl, carbamyl, loweralkylcarbamyl, or diloweralkylcarbamyl, —CH2ONO2, or —CH2OCOR131;
R132 is hydrogen or lower alkyl; and further wherein R131 and R130 may be taken together to form a ring cyclizing moiety selected from the group consisting of:




In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except that R20 of Z is described in U.S. Pat. No. 6,407,235 (incorporated by reference in its entirety) as comprising:
a) —C(O)(CH2)mC(O)OR40, wherein m is 1, 2, 3 or 4,




wherein R41 is —N(R42)(R43) and R42 and R43 are hydrogen or lower alkyl, or is a five or six member heterocyclyl or heteroaryl optionally substituted by lower alkyl, or

c) —C(O)(CH2)NHC(O)(CH2)N(R42)(R43).
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except that R20 of Z is described in U.S. Pat. No. 6,545,131 (incorporated by reference in its entirety) as comprising: CO—(CH═CH)n1—(CH2)n2—Ar—NH2, —CO—(CH2)n2—(CH═CH)n1—Ar—NH2, CO—(CH2)n2—(CH═CH)n1—CO—NH—Ar—NH2 and CO—(CH═CH)n1—(CH2)n2—CO—NH—Ar—NH2 and substituted variations thereof, where n1 and n2 are from 0 to 5, Ar is a substituted or unsubstituted aryl group. In some preferred embodiments, Z is CO—(CH2)n3—NH2, where n3 is from 0 to 15, preferably 3-15, and also preferably 6-12. Particularly preferred substituent groups within this class are 6-aminohexanoyl, 7-aminoheptanoyl, 8-aminooctanoyl, 9-aminononanoyl, 10-aminodecanoyl, 11-aminoundecanoyl, and 12-aminododecanoyl. These substituents are generally synthesized from the corresponding amino acids, 6-aminohexanoic acid, and so forth. The amino acids are N-terminal protected by standard methods, for example Boc protection. Dicyclohexylcarbodiimide (DCCl)-promoted coupling of the N-terminal protected substituent to thapsigargin, followed by standard deprotection reactions produces primary amine-containing thapsigargin analogs.
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except that R20 of Z is described in U.S. Pat. No. 7,115,573 (incorporated by reference in its entirety) as comprising:

    
    
        (1) an oligopeptide of the formula (AA)n-AA3-AA2-AA1, wherein: each AA independently represents an amino acid, n is 0 or 1, and when n is 1, then (AA)n is AA4 which represents any amino acid, AA3 represents isoleucine, AA2 represents any amino acid, and AA1 represents any amino acid,
        (2) a stabilizing group, and
        (3) optionally, a linker group not cleavable by a trouase, such as TOP (described in greater detail below)
    
    


wherein the oligopeptide is directly linked to the stabilizing group at a first attachment site of the oligopeptide and the oligopeptide is directly linked to the therapeutic agent or indirectly linked through the linker group to the therapeutic agent at a second attachment site of the oligopeptide,
wherein the stabilizing group hinders cleavage of the compound by enzymes present in whole blood, and
wherein the compound is cleavable by an enzyme associated with the target cell, the enzyme associated with the target cell being other than TOP (Thimet oligopeptidase). The compound preferably includes an oligopeptide that is resistant to cleavage by a trouase, particularly TOP, i.e., resistant to cleavage under physiological conditions. The optionally present linker group that is not cleavable by a trouase is not cleavable under physiological conditions.
The typical orientation of these portions of the prodrug is as follows: (stabilizing group)-(oligopeptide)-(optional linker group)-(therapeutic agent).
Direct linkage of two portions of the prodrug means a covalent bond exists between the two portions. The stabilizing group and the oligopeptide are therefore directly linked via a covalent chemical bond at the first attachment site of the oligopeptide, typically the N-terminus of the oligopeptide. When the oligopeptide and the therapeutic agent are directly linked then they are covalently bound to one another at the second attachment site of the oligopeptide. The second attachment site of the oligopeptide is typically the C-terminus of the oligopeptide, but may be elsewhere on the oligopeptide.
Indirect linkage of two portions of the prodrug means each of the two portions is covalently bound to a linker group. In an alternative embodiment, the prodrug has indirect linkage of the oligopeptide to the therapeutic agent. Thus, typically, the oligopeptide is covalently bound to the linker group which, in turn, is covalently bound to the therapeutic agent.
In an alternative embodiment, the orientation of the prodrug may be reversed so that a stabilizing group is attached to the oligopeptide at the C-terminus and the therapeutic agent is directly or indirectly linked to the N-terminus of the oligopeptide. Thus, in an alternative embodiment, the first attachment site of the oligopeptide may be the C-terminus of the oligopeptide and the second attachment site by the oligopeptide may be the N-terminus of the oligopeptide. The linker group may optimally be present between the therapeutic agent and the oligopeptide. The alternative embodiment of the prodrug of the invention functions in the same manner as does the primary embodiment.
The stabilizing group typically protects the prodrug from cleavage by proteinases and peptidases present in blood, blood serum, and normal tissue. Particularly, since the stabilizing group caps the N-terminus of the oligopeptide, and is therefore sometimes referred to as an N-cap or N-block, it serves to ward against peptidases to which the prodrug may otherwise be susceptible. A stabilizing group that hinders cleavage of the oligopeptide by enzymes present in whole blood is chosen from the following:

    
    
        (1) other than an amino acid, or
        (2) an amino acid that is either (i) a non-genetically-encoded amino acid or (ii) aspartic acid or glutamic acid attached to the N-terminus of the oligopeptide at the β-carboxyl group of aspartic acid or the γ-carboxyl group of glutamic acid.
    
    


For example, dicarboxylic (or a higher order carboxylic) acid or a pharmaceutically acceptable salt thereof may be used as a stabilizing group. Since chemical radicals having more than two carboxylic acids are also acceptable as part of the prodrug, the end group having dicarboxylic (or higher order carboxylic) acids is an exemplary N-cap. The N-cap may thus be a monoamide derivative of a chemical radical containing two or more carboxylic acids where the amide is attached onto the amino terminus of the peptide and the remaining carboxylic acids are free and uncoupled. For this purpose, the N-cap is preferably succinic acid, adipic acid, glutaric acid, or phthalic acid, with succinic acid and adipic acid being most preferred. Other examples of useful N-caps in the prodrug compound of the invention include diglycolic acid, fumaric acid, naphthalene dicarboxylic acid, pyroglutamic acid, acetic acid, 1- or 2-, naphthylcarboxylic acid, 1,8-naphthyl dicarboxylic acid, aconitic acid, carboxycinnamic acid, triazole dicarboxylic acid, gluconic acid, 4-carboxyphenyl boronic acid, a (PEG)n-analog such as polyethylene glycolic acid, butane disulfonic acid, maleic acid, nipecotic acid, and isonipecotic acid.
Further, a non-genetically encoded amino acid such as one of the following may also be used as the stabilizing group: β-Alanine, Thiazolidine-4-carboxylic acid, 2-Thienylalanine, 2-Naphthylalanine, D-Alanine, D-Leucine, D-Methionine, D-Phenylalanine, 3-Amino-3-phenylpropionic acid, γ-Aminobutyric acid, 3-amino-4,4-diphenylbutyric acid, Tetrahydroisoquinoline-3-carboxylic acid, 4-Aminomethylbenzoic acid, and Aminoisobutyric acid.
A linker group between the oligopeptide and the therapeutic agent may be advantageous for reasons such as the following: 1. As a spacer for steric considerations in order to facilitate enzymatic release of the AA1 amino acid or other enzymatic activation steps. 2. To provide an appropriate attachment chemistry between the therapeutic agent and the oligopeptide. 3. To improve the synthetic process of making the prodrug conjugate (e.g., by pre-derivitizing the therapeutic agent or oligopeptide with the linker group before conjugation to enhance yield or specificity.) 4. To improve physical properties of the prodrug. 5. To provide an additional mechanism for intracellular release of the drug.
Linker structures are dictated by the required functionality. Examples of potential linker chemistries are hydrazide, ester, ether, and sulfhydryl. Amino caproic acid is an example of a bifunctional linker group. When amino caproic acid is used as part of the linker group, it is not counted as an amino acid in the numbering scheme of the oligopeptide.
The oligopeptide moiety is linked at a first attachment site of the oligopeptide to a stabilizing group that hinders cleavage of the oligopeptide by enzymes present in whole blood, and directly or indirectly linked to a therapeutic agent at a second attachment site of the oligopeptide. The linkage of the oligopeptide to the therapeutic agent and the stabilizing group may be performed in any order or concurrently. The resulting conjugate is tested for cleavability by TOP. Test compounds resistant to cleavage by TOP are selected. The resulting conjugate may also be tested for stability in whole blood. Test compounds stable in whole blood are selected.
The combination of oligopeptide, stabilizing group, and optional linker of U.S. Pat. No. 7,115,573 is further described in US 2002-0142955, also incorporated herein by reference.
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except that R20 of Z is described in US 2004-0019017 A1 (incorporated by reference in its entirety and which describes caspase inhibitor prodrugs), as comprising:




wherein R51 is a saturated or unsaturated, straight-chain or branched, substituted or unsubstituted alkyl of 2 to 30, preferably 2 to 24, carbon atoms;
R52 is H or a phospholipid head group, preferably choline;
X is a direct covalent bond or a group C(O)LR53 wherein L is a saturated or unsaturated, straight-chain or branched, substituted or unsubstituted alkyl having from 2 to 15 carbon atoms, which optionally includes cyclic elements, and is optionally interrupted by one or more atoms selected from the group consisting of oxygen, sulfur and N(R54); R53 is selected from the group consisting of O, S and N(R54), wherein R54 is H or a saturated or unsaturated alkyl having 1 to 6 carbon atoms.
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except that R20 of Z is the Y moiety described in U.S. Pat. No. 7,115,573 (incorporated by reference in its entirety).
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except that R20 of Z is described in US 2006-0166903 A1 (incorporated by reference in its entirety, as comprising-X-L-O—P(O)(O−)—O—CH2—CH2—N(CH3)3+, wherein X and L are as described in US 2006-0166903A1.
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, except Z is one of the cleavable prodrug moieties described in U.S. Pat. No. 6,855,702, US 2005-0137141, and US 2006-0135594, all hereby incorporated by reference in their entirety.
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Rx is H or OH; and
        Z is —O—R20 or R21.
    
    


In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (1), (2) and (3) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Rx is H or OH; and
        Z is —O—R20 or R21, wherein
        R20 is —C(O)—C[(R10)(R10′)]1-4—NH(R13) or —C(O)—R10.
    
    


In a preferred embodiment of the present invention, the prodrugs of inhibitors of histone deacetylase comprise those of formula (2).
In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (2) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Rx is H or OH; and
        Z is —O—R20 or R21.
    
    


In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (2) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Rx is H or OH; and
        Z is —O—R20 or R21, wherein
        R20 is —C(O)—C[(R10)(R10′)]1-4—NH(R13) or —C(O)—R10.
    
    


In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (2) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl, wherein the substituents are preferably selected from the group consisting of —CF3, halo, heterocyclyl and fused heterocyclyl;
        L2 is saturated C3alkyl or C4alkyl, preferably unsubstituted;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Y2 is C1alkyl or C2alkyl, preferably C1alkyl, optionally substituted;
        Rx is H or OH, preferably H;
        Z is —O—R20 or R21;
        R20 is —C(O)—C[(R10)(R10′)]1-4—NH(R13) or —C(O)—R10;
        each R10 is independently selected from the group consisting of H, optionally substituted alkyl, optionally substituted-alkylphenyl, optionally substituted-alkylheteroaryl and optionally substituted heteroaryl;
        each R10′ is independently H or alkyl; or
        R10 and R10′ together with the atom to which they are attached form a C3 or C4spirocycloalkyl, preferably a C3spirocycloalkyl;
        R13 is selected from the group consisting of H, —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl-N(R10)(R10′), —C(O)-heteroaryl, —C(O)-aryl, —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl-aryl and —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl-heteroaryl; and
        R21 is amino acid-R13 (preferably the amino acid is lysine or arginine).
    
    


In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (2) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl, wherein the substituents are preferably selected from the group consisting of —CF3, halo, heterocyclyl and fused heterocyclyl;
        L2 is saturated C3alkyl or C4alkyl, preferably unsubstituted;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Y2 is C1alkyl or C2alkyl, preferably C1alkyl, optionally substituted;
        Rx is H or OH, preferably H;
        Z is —O—R20;
        R20 is —C(O)—C[(R10)(R10′)]1-4—NH(R13), preferably —C(O)—C[(R10)(R10′)]1-2—NH(R13), more preferably —C(O)—C[(R10)(R10′)]—NH(R13);
        each R10 is independently selected from the group consisting of H, optionally substituted alkyl and optionally substituted-alkylphenyl;
        each R10′ is independently H or alkyl; or
        R10 and R10′ together with the atom to which they are attached form a C3 or C4spirocycloalkyl, preferably a C3spirocycloalkyl; and
        R13 is H.
    
    


In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (2) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl, wherein the substituents are preferably selected from the group consisting of —CF3, halo, heterocyclyl and fused heterocyclyl;
        L2 is saturated C3alkyl or C4alkyl, preferably unsubstituted;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Y2 is C1alkyl or C2alkyl, preferably C1alkyl, optionally substituted;
        Rx is H or OH, preferably H;
        Z is R21;
        R21 is amino acid-R13 (preferably the amino acid is lysine or arginine); and
        R13 is H.
    
    


In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (2) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl, wherein the substituents are preferably selected from the group consisting of —CF3, halo, heterocyclyl and fused heterocyclyl;
        L2 is saturated C3alkyl or C4alkyl, preferably unsubstituted;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Y2 is C1alkyl or C2alkyl, preferably C1alkyl, optionally substituted;
        Rx is H or OH, preferably H;
        Z is —O—R20;
        R20 is —C(O)—R10; and
        R10 is selected from the group consisting of optionally substituted alkyl, optionally substituted-alkylphenyl, optionally substituted-alkylheteroaryl and optionally substituted heteroaryl.
    
    


In other embodiments, the prodrugs of inhibitors of histone deacetylase of the invention comprise those of formulae (2) as defined above, wherein

    
    
        Cy is optionally substituted aryl, preferably optionally substituted phenyl, wherein the substituents are preferably selected from the group consisting of —CF3, halo, heterocyclyl and fused heterocyclyl;
        L2 is saturated C3alkyl or C4alkyl, preferably unsubstituted;
        Ar is optionally substituted aryl, preferably optionally substituted phenyl;
        Y2 is C1alkyl or C2alkyl, preferably C1alkyl, optionally substituted;
        Rx is H or OH, preferably H;
        Z is —O—R
        R20 is —C(O)—C[(R10)(R10′)]—NH(R13), wherein R10 and R10′ together with the atom to which they are attached form a C3 or C4spirocycloalkyl, preferably a C3spirocycloalkyl; and
        R13 is selected from the group consisting of H, —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl-N(R10)(R10′), —C(O)-heteroaryl, —C(O)-aryl, —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl, —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl-aryl and —C(O)—CH[N(R10)(R10′)]-C1-C6alkyl-heteroaryl, wherein R10 and R10′ are each independently selected from H and C1-C6alkyl, preferably H.
    
    


Preferred prodrugs of the invention include those in Table A:







TABLE A







 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 








 















Preferred prodrug compounds of the invention are cleavable (e.g., hydrolysable) in mammalian and/or fungal pathogen cells into compounds (cleavage products) in which Z in formulae (1), (2), and (3) is —OH. Such cleavage products are active histone deacetylase inhibitors. Thus, according to another aspect, the invention provides compounds of formulae (1), (2), and (3) as defined above (and pharmaceutically acceptable salts thereof) with the exception that Z is —OH. Among the preferred cleavage compounds are those with structure:




Preferred cleavage products of the prodrug compounds of the invention include those in Table A in which Z is —OH.
All compounds of the invention, whether prodrug or corresponding cleavage product, can be racemic or diastereomerically or enantiomerically enriched. In addition, compounds of the invention, whether prodrug or corresponding cleavage product, can be in the form of a hydrate, solvate, pharmaceutically acceptable salt, and/or complex.
Synthesis
Compounds of formula Cy-L1-Ar—Y1—C(O)—NH—O—H, wherein L1 is —S(O)2NH—, preferably may be prepared according to the synthetic routes depicted in Schemes 1-5. Accordingly, in certain preferred embodiments, compounds I are preferably prepared according to the general synthetic route depicted in Scheme 1. Thus, a sulfonyl chloride (II) is treated with an amine (III) in a solvent such as methylene chloride in the presence of an organic base such as triethylamine. Treatment of the crude product with a base such as sodium methoxide in an alcoholic solvent such as methanol effects cleavage of any dialkylated material and affords the sulfonamide (IV). Hydrolysis of the ester function in IV can be effected by treatment with a hydroxide base, such as lithium hydroxide, in a solvent mixture such as tetrahydrofuran and methanol to afford the corresponding acid (V).




In some embodiments, conversion of the acid V to the hydroxamic acid I may be accomplished by coupling V with a protected hydroxylamine, such as tetrahydropyranylhydroxylamine (NH2OTHP), to afford the protected hydroxamate VI, followed by acidic hydrolysis of VI to provide the hydroxamic acid I. The coupling reaction is preferably accomplished with the coupling reagent dicyclohexylcarbodiimide (DCC) in a solvent such as methylene chloride (Method A) or with the coupling reagent 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide in presence of N-hydroxy benzotriazole in an aprotic solvent such as dimethylformamide (Method D). Other coupling reagents are known in the art and may also be used for this reaction. Hydrolysis of VI is preferably effected by treatment with an organic acid such as camphorsulfonic acid in a protic solvent such as methanol.
Alternatively, in some other embodiments, acid V is converted to the corresponding acid chloride, preferably by treatment with oxalic chloride, followed by the addition of a protected hydroxylamine such as O-trimethylsilylhydroxylamine in a solvent such as methylene chloride, which then provides the hydroxylamine I upon workup (Method C).
In still other embodiments, the ester IV is preferably treated with hydroxylamine in a solvent such as methanol in the presence of a base such as sodium methoxide to furnish the hydroxylamine I directly (Method B).




Compounds of formula X and XIV preferably are prepared according to the general procedure outlined in Scheme 2. Thus, an aminoaryl halide (VII) is treated with a sulfonyl chloride in presence of a base such as triethylamine, followed by treatment with an alkoxide base, to furnish the sulfonamide VIII. One of skill in the art will recognize that reverse sulfonamide analogs can be readily prepared by an analogous procedure, treating a haloarenesulfonyl halide with an arylamine.
Compound VIII is coupled with a terminal acetylene or olefinic compound in the presence of a palladium catalyst such as tetrakis(triphenylphosphine)palladium(0) in a solvent such as pyrrolidine to afford IX.
Oxidation of the compound of formula IX (X═CH2OH), followed by homologation of the resulting aldehyde using a Wittig type reagent such as carbethoxymethylenetriphenylphosphorane in a solvent such as acetonitrile, gives the compound of formula XI. Basic hydrolysis of XI, such as by treatment with lithium hydroxide in a mixture of THF and water, provides the acid XII. Hydrogenation of XII may preferably be performed over a palladium catalyst such as Pd/C in a protic solvent such as methanol to afford the saturated acid XIII. Coupling of the acid XIII with an O-protected hydroxylamine such as O-tetrahydropyranylhydroxylamine is effected by treatment with a coupling reagent such as 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide in the presence of N-hydroxybenzotriazole (HOBT), or N,N-dicyclohexylcarbodiimide (DCC), in a solvent such as DMF, followed by deprotection to furnish the compound of general formula XIV.
The acid IX, wherein X═COOH, may be coupled directly with an O-protected hydroxylamine such as O-tetrahydropyranylhydroxylamine, followed by deprotection of the hydroxy protecting group to furnish the hydroxamic acid X.
Compounds of formula Cy-L1-Ar—Y1—C(O)—NH—O—H, wherein L1 is —C(O)NH—, preferably may be prepared according to the synthetic routes analogous to those depicted in Schemes 1-2, substituting acid chloride starting materials for the sulfonyl chloride starting materials in those Schemes.




Compounds of the formula Cy-L2-Ar—Y2—C(O)—NH—O—H are preferably prepared according to the synthetic routes outlined in Schemes 3-5. Accordingly, in certain preferred embodiments, compounds of formulae XIX and XXI (L2=—C(O)—CH═CH— or —C(O)—CH2CH2—) preferably are prepared according to the route described in Scheme 3. Thus, a substituted aryl acetophenone (XV) is treated with an aryl aldehyde (XVI) in a protic solvent such as methanol in the presence of a base such as sodium methoxide to afford the enone XVII.
The acid substituent of XVII (R═H) is coupled with an O-protected hydroxylamine such as O-tetrahydropyranylhydroxylamine (R1=tetrahydropyranyl) to afford the O-protected-N-hydroxybenzamide XVIII. The coupling reaction is preferably performed by treating the acid and hydroxylamine with dicyclohexylcarbodiimide in a solvent such as methylene chloride or with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide in the presence of N-hydroxybenzotriazole in a solvent such as dimethylformamide. Other coupling reagents are known in the art and may also be used in this reaction. O-Deprotection is accomplished by treatment of XVIII with an acid such as camphorsulfonic acid in a solvent such as methanol to afford the hydroxamic acid XIX (L2=—C(O)—CH═CH—).
Saturated compounds of formula XXI (L=—C(O)—CH2CH2—) are preferably prepared by hydrogenation of XVII (R=Me) over a palladium catalyst, such as 10% Pd/C, in a solvent such as methanol-tetrahydrofuran. Basic hydrolysis of the resultant product XIX with lithium hydroxide, followed by N-hydroxy amide formation and acid hydrolysis as described above, then affords the hydroxamic acid XXI.




Compounds of formula XXVI (L2=—(CH2)o+2—) are preferably prepared by the general procedures described in Schemes 4 and 5. Thus, in some embodiments, a terminal olefin (XXII) is coupled with an aryl halide (XXIII) in the presence of a catalytic amount of a palladium source, such as palladium acetate or tris(dibenzylideneacetone)dipalladium(0), a phosphine, such as triphenylphosphine, and a base, such as triethylamine, in a solvent such as acetonitrile to afford the coupled product XXIV. Hydrogenation, followed by N-hydroxyamide formation and acid hydrolysis, as described above, affords the hydroxamic acid XXVI.




Alternatively, in some other embodiments, a phosphonium salt of formula XXVII is treated with an aryl aldehyde of formula XXVIII in the presence of base, such as lithium hexamethyldisilazide, in a solvent, such as tetrahydrofuran, to produce the compound XXIV. Hydrogenation, followed by N-hydroxyamide formation and acidic hydrolysis, then affords the compounds XXVI.




Compounds of formula Cy-L-Ar—Y—C(O)—NH—Z, wherein L is L1 or L2, Y is Y1 or Y2, and Z is anilinyl or pyridyl, are preferably prepared according to synthetic routes outlined in Scheme 6. An acid of formula Cy-L-Ar—Y—C(O)—OH (XXIX), prepared by one of the methods shown in Schemes 1-5, is converted to the corresponding acid chloride XXX according to standard methods, e.g., by treatment with sodium hydride and oxalyl chloride. Treatment of XXX with 2-aminopyridine and a tertiary base such as N-methylmorpholine, preferably in dichloromethane at reduced temperature, then affords the pyridyl amide XXXI. In a similar fashion, the acid chloride XXX may be treated with 1,2-phenylenediamine to afford the anilinyl amide XXXII. Alternatively, the acid chloride XXX may be treated with a mono-protected 1,2-phenylenediamine, such as 2-(t-BOC-amino)aniline, followed by deprotection, to afford XXXII.
In another alternative procedure, the acid XXIX may be activated by treatment with carbonyldiimidazole (CDI), followed by treatment with 1,2-phenylenediamine and trifluoroacetic acid to afford the anilinyl amide XXXII.




Compounds of formula XXXVIII (L2=—C(O)-alkylene-) preferably are prepared according to the general procedure depicted in Scheme 7. Thus, Aldol condensation of ketone XXXIII (R1═H or alkyl) with aldehyde XXXIV affords the adduct XXXV. The adduct XXXV may be directly converted to the corresponding hydroxamic acid XXXVI, or may first undergo hydrogenation to afford the saturated compound XXVII and then be converted to the hydroxamic acid XXXVIII.




Compounds of formula Cy-L2-Ar—Y2—C(O)—NH—O—H, wherein one of the carbon atoms in L is replaced with S, S(O), or S(O)2 preferably are prepared according to the general procedure outlined in Scheme 8. Thus, thiol XXXIX is added to olefin XL to produce XL1. The reaction is preferably conducted in the presence of a radical initiator such as 2,2′-azobisisobutyronitrile (AIBN) or 1,1′-azobis(cyclohexanecarbonitrile) (VAZOTM). Sulfide oxidation, preferably by treatment with m-chloroperbenzoic acid (mCPBA), affords the corresponding sulfone, which is conveniently isolated after conversion to the methyl ester by treatment with diazomethane. Ester hydrolysis then affords the acid XLII, which is converted to the hydroxamic acid XLIII according to any of the procedures described above. The sulfide XL1 also may be converted directly to the corresponding hydroxamic acid XLIV, which then may be selectively oxidized to the sulfoxide XLV, for example, by treatment with hydrogen peroxide and tellurium dioxide.
Alternatively, compounds of Cy-L2-Ar—Y2—C(O)—NH—O—H can be prepared according to Scheme 9. In Scheme 9, haloaryl acetic acid XLVI is esterified, by, for example, treatment with HCl in dioxane in the presence of an alcohol such as methanol, to afford acetate XLVII. Paladium coupling of acetate XLVII with alkyne XLVIII with, for example (Ph3P)4Pd in DME and diethylamine in the presence of CuI, produces XLVIX, which is subsequently reduced under H2 and, for example, Pd/C in methanol, to afford XLVX. N-hydroxyamide formation and acid hydrolysis, as described above, then leads to XLVXI.




Compounds of formulas (1)-(3) can be prepared as depicted in Scheme 10. XLVXI is treated with an amino acid XLVXII under standard peptide coupling conditions, such as, for example, EDC and HOBt in DMF, to afford the protected acetamide XLVXIII, which is subsequently deprotected to yield the prodrug XLVXIV.




Other compounds of formula (1)-(3) can be prepared by methods known by those skilled in the art. Examples of such methods can be found in U.S. Pat. Nos. 4,443,435; 6,407,235; 6,545,131; 6,855,702; 7,115,573; United States Patent Application Nos. US 2002-0142955, US 2004-0019017, US 2005-0137141, US 2006-0135594, US 2006-0166903 and international publication WO 2005/097747, all of which are incorporated herein by reference.
Pharmaceutical Compositions
In a second aspect, the invention provides pharmaceutical compositions comprising a prodrug of an inhibitor of histone deacetylase represented by any one of formulae (1)-(3) and a pharmaceutically acceptable carrier, excipient, or diluent. Compounds of the invention (whether a prodrug or a hydrolzyation product) or compositions thereof may be formulated by any method well known in the art and may be prepared for administration by any route, including, without limitation, parenteral, oral, sublingual, transdermal, topical, intranasal, intratracheal, or intrarectal. In certain preferred embodiments, compounds of the invention (whether a prodrug or a hydrolzyation product) or compositions thereof are administered intravenously in a hospital setting. In certain other preferred embodiments, administration may preferably be by the oral route.
The characteristics of the carrier will depend on the route of administration. As used herein, the term “pharmaceutically acceptable” means a non-toxic material that is compatible with a biological system such as a cell, cell culture, tissue, or organism, and that does not interfere with the effectiveness of the biological activity of the active ingredient(s). Thus, compositions according to the invention may contain, in addition to the inhibitor, diluents, fillers, salts, buffers, stabilizers, solubilizers, and other materials well known in the art. The preparation of pharmaceutically acceptable formulations is described in, e.g. Remington's Pharmaceutical Sciences, 18th Edition, ed. A. Gennaro, Mack Publishing Co., Easton, Pa., 1990.
Inhibition of Histone Deacetylase
In a third aspect, the invention provides a method of inhibiting histone deacetylase in a cell, comprising contacting a cell in which inhibition of histone deacetylase is desired with a prodrug of an inhibitor of histone deacetylase according to any of formulas (1)-(3).
Measurement of the enzymatic activity of a histone deacetylase can be achieved using known methodologies. For example, Yoshida et al., J. Biol. Chem., 265: 17174-17179 (1990), describes the assessment of histone deacetylase enzymatic activity by the detection of acetylated histones in trichostatin A treated cells. Taunton et al., Science, 272: 408-411 (1996), similarly describes methods to measure histone deacetylase enzymatic activity using endogenous and recombinant HDAC-1. Both of these references are hereby incorporated by reference in their entirety.
In some preferred embodiments, the histone deacetylase inhibitor interacts with and reduces the activity of all histone deacetylases in the cell. In some other preferred embodiments according to this aspect of the invention, the histone deacetylase inhibitor interacts with and reduces the activity of fewer than all histone deacetylases in the cell. In certain preferred embodiments, the inhibitor interacts with and reduces the activity of one histone deacetylase (e.g., HDAC-1), but does not interact with or reduce the activities of other histone deacetylases (e.g., HDAC-2, HDAC-3, HDAC-4, HDAC-5, HDAC-6, HDAC-7, HDAC-8, HDAC-9, HDAC-10, and HDAC-11). As discussed below, certain particularly preferred histone deacetylase inhibitors are those that interact with and reduce the enzymatic activity of a histone deacetylase that is involved in tumorigenesis. Certain other preferred histone deacetylase inhibitors interact with and reduce the enzymatic activity of a fungal histone deacetylase.
Preferably, the method according to the third aspect of the invention causes an inhibition of cell proliferation of the contacted cells. The phrase “inhibiting cell proliferation” is used to denote an ability of an inhibitor of histone deacetylase to retard the growth of cells contacted with the inhibitor as compared to cells not contacted. An assessment of cell proliferation can be made by counting contacted and non-contacted cells using a Coulter Cell Counter (Coulter, Miami, Fla.) or a hemacytometer, or other appropriate method (which may depend on the cell type being counted) known to those of skill in the art. Where the cells are in a solid growth (e.g., a solid tumor or organ), such an assessment of cell proliferation can be made by measuring the growth with calipers and comparing the size of the growth of contacted cells with non-contacted cells.
Preferably, growth of cells contacted with the prodrug of the inhibitor is retarded by at least 50% as compared to growth of non-contacted cells. More preferably, cell proliferation is inhibited by 100% (i.e., the contacted cells do not increase in number). Most preferably, the phrase “inhibiting cell proliferation” includes a reduction in the number or size of contacted cells, as compared to non-contacted cells. Thus, a cleavage (e.g., hydrolyzation) product of a prodrug of an inhibitor of histone deacetylase according to the invention that inhibits cell proliferation in a contacted cell may induce the contacted cell to undergo growth retardation, to undergo growth arrest, to undergo programmed cell death (i.e., to apoptose), or to undergo necrotic cell death.
The cell proliferation inhibiting ability of the histone deacetylase inhibitors according to the invention allows the synchronization of a population of asynchronously growing cells. For example, the hydrolyzation products of the prodrugs of histone deacetylase inhibitors of the invention may be used to arrest a population of non-neoplastic cells grown in vitro in the G1 or G2 phase of the cell cycle. Such synchronization allows, for example, the identification of gene and/or gene products expressed during the G1 or G2 phase of the cell cycle. Such a synchronization of cultured cells may also be useful for testing the efficacy of a new transfection protocol, where transfection efficiency varies and is dependent upon the particular cell cycle phase of the cell to be transfected. Use of the prodrugs of histone deacetylase inhibitors of the invention allows the synchronization of a population of cells, thereby aiding detection of enhanced transfection efficiency.
In some preferred embodiments, the contacted cell is a neoplastic cell. The term “neoplastic cell” is used to denote a cell that shows aberrant cell growth. Preferably, the aberrant cell growth of a neoplastic cell is increased cell growth. A neoplastic cell may be a hyperplastic cell, a cell that shows a lack of contact inhibition of growth in vitro, a benign tumor cell that is incapable of metastasis in vivo, or a cancer cell that is capable of metastasis in vivo and that may recur after attempted removal. The term “tumorigenesis” is used to denote the induction of cell proliferation that leads to the development of a neoplastic growth. In some embodiments, the cleavage product of a prodrug of a histone deacetylase inhibitor of the invention induces cell differentiation in the contacted cell. Thus, a neoplastic cell, when contacted with a prodrug of an inhibitor of histone deacetylase of the invention may be induced to differentiate, resulting in the production of a daughter cell that is phylogenetically more advanced than the contacted cell. In certain other preferred embodiments, the contacted cell is a fungal cell.
In some preferred embodiments, the contacted cell is in an animal. Thus, the invention provides a method for treating a cell proliferative disease or condition in an animal, or treating a fungal infection, comprising administering to an animal in need of such treatment a therapeutically effective amount of a prodrug of a histone deacetylase inhibitor of the invention. Preferably, the animal is a mammal, more preferably a domesticated mammal. Most preferably, the animal is a human.
The term “cell proliferative disease or condition” is meant to refer to any condition characterized by aberrant cell growth, preferably abnormally increased cellular proliferation. Examples of such cell proliferative diseases or conditions include, but are not limited to, cancer, restenosis, and psoriasis. In particularly preferred embodiments, the invention provides a method for inhibiting neoplastic cell proliferation in an animal comprising administering to an animal having at least one neoplastic cell present in its body a therapeutically effective amount of a prodrug of a histone deacetylase inhibitor of the invention.
It is contemplated that some cleavage products of the prodrugs of the invention have inhibitory activity against a histone deacetylase from a protozoal source. Thus, the invention also provides a method for treating or preventing a protozoal disease or infection, comprising administering to an animal in need of such treatment a therapeutically effective amount of a prodrug of a histone deacetylase inhibitor of the invention. Preferably the animal is a mammal, more preferably a human. Preferably, the histone deacetylase inhibitor used according to this embodiment of the invention inhibits a protozoal histone deacetylase to a greater extent than it inhibits mammalian histone deacetylases, particularly human histone deacetylases.
The present invention further provides a method for treating a fungal disease or infection comprising administering to an animal in need of such treatment a therapeutically effective amount of a prodrug of a histone deacetylase inhibitor of the invention. Preferably the animal is a mammal, more preferably a human. Preferably, the histone deacetylase inhibitor used according to this embodiment of the invention inhibits a fungal histone deacetylase to a greater extent than it inhibits mammalian histone deacetylases, particularly human histone deacetylases.
The term “therapeutically effective amount” is meant to denote a dosage sufficient to cause inhibition of histone deacetylase activity in the cells of the subject, or a dosage sufficient to inhibit cell proliferation or to induce cell differentiation in the subject. Administration may be by any route, including, without limitation, parenteral, oral, sublingual, transdermal, topical, intranasal, intratracheal, or intrarectal. In certain particularly preferred embodiments, prodrugs of the invention are administered intravenously in a hospital setting. In certain other preferred embodiments, administration may preferably be by the oral route.
When administered systemically, the prodrug of an histone deacetylase inhibitor is preferably administered at a sufficient dosage to attain a blood level of the inhibitor from about 0.01 μM to about 100 μM, more preferably from about 0.05 μM to about 50 μM, still more preferably from about 0.1 μM to about 25 μM, and still yet more preferably from about 0.5 μM to about 25 μM. For localized administration, much lower concentrations than this may be effective, and much higher concentrations may be tolerated. One of skill in the art will appreciate that the dosage of histone deacetylase inhibitor necessary to produce a therapeutic effect may vary considerably depending on the tissue, organ, or the particular animal or patient to be treated.
In certain preferred embodiments of the third aspect of the invention, the method further comprises contacting the cell with an antisense oligonucleotide that inhibits the expression of a histone deacetylase. The combined use of a nucleic acid level inhibitor (i.e., antisense oligonucleotide) and a protein level inhibitor (i.e., inhibitor of histone deacetylase enzyme activity) results in an improved inhibitory effect, thereby reducing the amounts of the inhibitors required to obtain a given inhibitory effect as compared to the amounts necessary when either is used individually. Antisense oligonucleotides according to this aspect of the invention, when directed to mammalian HDAC, are complementary to regions of RNA or double-stranded DNA that encode HDAC-1, HDAC-2, HDAC-3, HDAC-4, HDAC-5, HDAC-6, HDAC7, HDAC-8, HDAC-9, HDAC-10 and/or HDAC-11.
For purposes of the invention, the term “oligonucleotide” includes polymers of two or more deoxyribonucleosides, ribonucleosides, or 2′-O-substituted ribonucleoside residues, or any combination thereof. Preferably, such oligonucleotides have from about 6 to about 100 nucleoside residues, more preferably from about 8 to about 50 nucleoside residues, and most preferably from about 12 to about 30 nucleoside residues. The nucleoside residues may be coupled to each other by any of the numerous known internucleoside linkages. Such internucleoside linkages include without limitation phosphorothioate, phosphorodithioate, alkylphosphonate, alkylphosphonothioate, phosphotriester, phosphoramidate, siloxane, carbonate, carboxymethylester, acetamidate, carbamate, thioether, bridged phosphoramidate, bridged methylene phosphonate, bridged phosphorothioate and sulfone internucleoside linkages. In certain preferred embodiments, these internucleoside linkages may be phosphodiester, phosphotriester, phosphorothioate, or phosphoramidate linkages, or combinations thereof. The term oligonucleotide also encompasses such polymers having chemically modified bases or sugars and/or having additional substituents, including without limitation lipophilic groups, intercalating agents, diamines and adamantane. For purposes of the invention the term “2′-O-substituted” means substitution of the 2′ position of the pentose moiety with an —O-lower alkyl group containing 1-6 saturated or unsaturated carbon atoms, or with an —O-aryl or allyl group having 2-6 carbon atoms, wherein such alkyl, aryl or allyl group may be unsubstituted or may be substituted, e.g. with halo, hydroxy, trifluoromethyl, cyano, nitro, acyl, acyloxy, alkoxy, carboxyl, carbalkoxyl, or amino groups; or such 2′ substitution may be with a hydroxy group (to produce a ribonucleoside), an amino or a halo group, but not with a 2′-H group. The term “oligonucleotide” also encompasses linked nucleic acid and peptide nucleic acid.
Particularly preferred antisense oligonucleotides utilized in this aspect of the invention include chimeric oligonucleotides and hybrid oligonucleotides.
For purposes of the invention, a “chimeric oligonucleotide” refers to an oligonucleotide having more than one type of internucleoside linkage. One preferred example of such a chimeric oligonucleotide is a chimeric oligonucleotide comprising a phosphorothioate, phosphodiester or phosphorodithioate region, preferably comprising from about 2 to about 12 nucleotides, and an alkylphosphonate or alkylphosphonothioate region (see e.g., Pederson et al. U.S. Pat. Nos. 5,635,377 and 5,366,878). Preferably, such chimeric oligonucleotides contain at least three consecutive internucleoside linkages selected from phosphodiester and phosphorothioate linkages, or combinations thereof.
For purposes of the invention, a “hybrid oligonucleotide” refers to an oligonucleotide having more than one type of nucleoside. One preferred example of such a hybrid oligonucleotide comprises a ribonucleotide or 2′-O-substituted ribonucleotide region, preferably comprising from about 2 to about 122′-O-substituted nucleotides, and a deoxyribonucleotide region. Preferably, such a hybrid oligonucleotide will contain at least three consecutive deoxyribonucleosides and will also contain ribonucleosides, 2′-O-substituted ribonucleosides, or combinations thereof (see e.g. Metelev and Agrawal, U.S. Pat. No. 5,652,355).
The exact nucleotide sequence and chemical structure of an antisense oligonucleotide utilized in the invention can be varied, so long as the oligonucleotide retains its ability to inhibit expression of the gene of interest. This is readily determined by testing whether the particular antisense oligonucleotide is active by quantitating the mRNA encoding a product of the gene, or in a Western blotting analysis assay for the product of the gene, or in an activity assay for an enzymatically active gene product, or in a soft agar growth assay, or in a reporter gene construct assay, or an in vivo tumor growth assay, all of which are described in detail in this specification or in Ramchandani et al. (1997) Proc. Natl. Acad. Sci. USA 94: 684-689.
Antisense oligonucleotides utilized in the invention may conveniently be synthesized on a suitable solid support using well known chemical approaches, including H-phosphonate chemistry, phosphoramidite chemistry, or a combination of H-phosphonate chemistry and phosphoramidite chemistry (i.e., H-phosphonate chemistry for some cycles and phosphoramidite chemistry for other cycles). Suitable solid supports include any of the standard solid supports used for solid phase oligonucleotide synthesis, such as controlled-pore glass (CPG) (see, e.g. Pon, R. T. (1993) Methods in Molec. Biol. 20: 465-496).
Particularly, preferred oligonucleotides have nucleotide sequences of from about 13 to about 35 nucleotides which include the nucleotide sequences shown in Tables 1-3. Yet additional particularly preferred oligonucleotides have nucleotide sequences of from about 15 to about 26 nucleotides of the nucleotide sequences shown in Tables 1-3.









TABLE 1





SEQ ID

TARGET


NO.
SEQUENCE
(**)







 1
5′-GAG ACA GCA GCA CCA GCG GG-3′
17-36


 


 2
5′-ATG ACC GAG TGG GAG ACA GC-3′
21-49


 


 3
5′-GGA TGA CCG AGT GGG AGA CA-3′
31-50


 


 4
5′-CAG GAT GAC CGA GTG GGA GA-3′
33-52


 


 5
5′-TGT GTT CTC AGG ATG ACC GA-3′
41-60


 


 6
5′-GAG TGA CAG AGA CGC TCA GG-3′
62-81


 


 7
5′-TTC TGG CTT CTC CTC CTT GG-3′
1504-1523


 


 8
5′-CTT GAC CTC CTC CTT GAC CC-3′
1531-1550


 


 9
5′-GGA AGC CAG AGC TGG AGA GG-3′
1565-1584


 


10
5′-GAA ACG TGA GGG ACT CAG CA-3′
1585-1604


 


11
5′-CCG TCG TAG TAG TAA CAG ACT
138-160



TT-3′



 


12
5′-TGT CCA TAA TAG TAA TTT CCA
166-187



A-3′



 


13
5′-CAG CAA ATT ATG AGT CAT GCG
211-236



GAT TC-3′





(**) target reference numbering is in accordance with HDAC-1, GenBank Accession Number U50079.















TABLE 2





SEQ ID

TARGET


NO.
SEQUENCE
(***)







14
5′-CTC CTT GAC TGT ACG CCA TG-3′
 1-20


 


15
5′-TGC TGC TGC TGC TGC TGC CG-3′
121-141


 


16
5′-CCT CCT GCT GCT GCT GCT GC-3′
132-152


 


17
5′-CCG TCG TAG TAG TAG CAG ACT
138-160



TT-3′



 


18
5′-TGT CCA TAA TAA TAA TTT CCA
166-187



A-3′



 


19
5′-CAG CAA GTT ATG GGT CAT GCG
211-236



GAT TC-3′



 


20
5′-GGT TCC TTT GGT ATC TGT TT-3′
1605-1625





(***) target reference numbering is in accordance with HDAC-2, GenBank Accession Number U31814.















TABLE 3





SEQ ID

TARGET


NO.
SEQUENCE
(***)







21
5′-GCT GCC TGC CGT GCC CAC CC-3′
514-533





(***) target reference numbering is in accordance with HDAC-4






The following examples are intended to further illustrate certain preferred embodiments of the invention, and are not intended to limit the scope of the invention.
EXAMPLES
Preparation of Amines
Methyl-3-aminophenylacetate (1)




To a solution of 3-aminophenylacetic acid (3 g, 19.85 mmol) in methanol (50 mL) at room temperature was added HCl conc. (37%, 7.5 mL). The mixture was stirred 6 h at room temperature then treated with a saturated aqueous solution of NaHCO3. The solvent was removed under reduced pressure then the aqueous phase was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) and evaporated. The crude mixture was purified by flash chromatography using hexane/AcOEt (1:1) yielding 1 as a yellow oil (3.06 g, 79%).
1H NMR: (300 MHz, CDCl3): δ 7.10 (t, J=8 Hz, 1H), 6.68-6.58 (m, 3H), 3.69-3.65 (m, 5H), 3.53 (s, 2H).
Methyl-4-aminophenyl benzoate (2)




To a solution of 4-aminobenzoic acid (10 g, 72.92 mmol) in methanol (200 mL) at room temperature was added HCl conc. (37%, 25 mL). The solution mixture was heated overnight at 70° C. Once the solution was clear (completed) the reaction was treated with a saturated aqueous solution of NaHCO3 and Na2CO3 powder until pH 9. The solvent was then evaporated under reduced pressure and the aqueous phase was extracted several times with AcOEt. The combined organic extracts were dried over (MgSO4) and evaporated. The crude product 2 (9.30 g 85%) was obtained as a beige solid and was clean enough to use without further purification.
1H NMR: (300 MHz, CDCl3): δ 7.85 (d, J=8 Hz, 2H), 6.63 (d, J=8 Hz, 2H), 4.04 (broad s. 2H), 3.85 (s. 3H).
Methyl-4-aminophenylacetate (3)




To a solution of 4-aminophenylacetic acid (10 g, 66.2 mmol) in methanol (150 mL) at room temperature was added HCl conc. (37% 25 mL). The mixture became yellow and was stirred overnight. The reaction mixture was then quenched with a saturated aqueous solution of NaHCO3. The methanol was evaporated under reduced pressure and the aqueous layer was extracted several times with AcOEt. The combined organic extracts were dried over (MgSO4) and evaporated. The crude residue was purified by flash chromatography using hexane/AcOEt (4:1) as solvent mixture yielding 3 as a yellow oil (9.44 g, 74%).
1H NMR: (300 MHz, CDCl3): δ 7.05 (d, J=10 Hz, 2H), 6.65 (d, J=10 Hz, 2H), 3.65 (s, 3H), 3.63 (broad s, 2H), 3.51 (s, 2H).
Example 1
2-[4-benzo[b]thiophene-2-sulfonylamino)-phenyl]-N-hydroxy-acetamide (4)




Step 1: Methyl-2-[4-benzo[b]thiophene-2-sulfonylamino)-phenyl]-acetate (5)





To a solution of 3 (500 mg, 2.56 mmol), in CH2Cl2 (8 mL) at room temperature were added Et3N (712 μμL, 5.12 mmol) followed by 2-benzothiophenesulfonyl chloride (712 mg, 3.07 mmol). The mixture was stirred overnight at room temperature then quenched with a saturated aqueous solution of NaHCO3. The phases were separated and the aqueous layer was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) and evaporated. The mixture of the mono and bis alkylated products were dissolved in methanol ( ̃8 mL) and NaOMe was added (691 mg, 12.8 mmol). The resulting mixture was heated at 60° C. for 30 min the HCl 1N was added until pH 2. Then a saturated aqueous solution of NaHCO3 was added until pH 7-8. The solvent was evaporated under reduced pressure then the aqueous layer was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) and evaporated. The residue was purified by flash chromatography using toluene/AcOEt 7:3 as solvent mixture and a second flash chromatography using CH2Cl2/acetone 98:2 as solvent yielding the title compound 5 as yellowish powder (487 mg, 53%).
1H NMR: (300 MHz, CDCl3): δ 7.80 (d, J=8 Hz, 2H), 7.75 (s, 1H), 7.44 (m, 2H), 7.14 (m, 4H), 6.79 (broad s, 1H) 3.67 (s, 3H), 3.56 (s, 2H)




Step 2: 2-[4-benzo[b]thiophene-2-sulfonylamino)-phenyl]-acetic acid (6)

To a solution of 5 from step 1 (451 mg, 1.25 mmol) in a solvent mixture of THF (20 mL) and H2O (20 mL) at room temperature was added LiOH (524 mg, 12.5 mmol). The mixture was stirred for 2 h at room temperature and then was treated with a saturated aqueous solution of NH4Cl. The resulting solution was extracted several times with AcOEt. The combined organic extracts were dried over (MgSO4). The crude residue was then purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture yielding the title compound 6 as white solid (404 mg, 93%).
1H NMR: (300 MHz, DMSO-d6): δ 8.03 (d, J=8 Hz, 1H), 7.97 (d, J=7 Hz, 1H), 7.92 (s, 1H), 7.50-7.45 (m, 2H), 7.13-7.06 (m, 4H), 3.44 (s, 2H).
Step 3: 2-[4-benzo[b]thiophene-2-sulfonylamino)-phenyl]-N-hydroxy-acetamide (4)




Method A:

To a solution of 6 (150 mg, 0.432 mmol) in a solvent mixture of CH2Cl2 (10 mL) and THF (5 mL) was added at room temperature 1,3-dicyclohexylcarbodiimide (DCC, 116 mg, 0.563 mmol). The reaction mixture was stirred 30 min at room temperature then NH2OTHP (76 mg, 0.650 mmol) and dimethylaminopyridine (DMAP, 5 mg) were added. The solution was stirred over night at room temperature and the solvents were evaporated under reduced pressure. The crude material was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent. The residue was dissolved in MeOH ( ̃10 mL) and 10-camphorsulfonic acid (CSA, 100 mg, 0.432 mmol) was added. The mixture was stirred at room temperature overnight then treated with a saturated aqueous solution of NaHCO3. The solvent was evaporated under reduced pressure and the aqueous phase was extracted several times with CH2Cl2 (3×) and AcOEt (3×). The combined organic extracts were dried over (MgSO4) and evaporated. The crude product was purified by preparative high pressure liquid chromatography on reversed phase silica gel using a gradient of water/CH3CN (10-65%) yielding the title compound 4 as yellowish solid (70 mg, 45%).
1H NMR (300 MHz, CD3OD): δ 7.92-7.88 (m, 2H), 7.80 (s, 1H), 7.50-7.45 (m, 2H), 7.23-7.16 (m, 4H) 3.35 (s, 2H).
Except where otherwise indicated, the following compounds were prepared by procedures analogous to those described in Example 1, but substituting the sulfonyl chloride indicated for 2-benzothiophenesulfonyl chloride in step 1.
Example 2
2-[4-(2-nitrobenzenesulfonylamino)-phenyl]-N-hydroxy-acetamide (7)




Sulfonyl chloride: 2-nitrobenzenesulfonyl chloride
Yield: Step 1: 82%
Yield: Step 2: 99%
Yield: Step 3: 19%
1H NMR (300 MHz, DMSO-d6); δ 10.59 (s, 1H); 8.78 (s, 1H); 7.94 (s, 2H), 7.81 (s, 2H), 7.20-7.02 (m, 4H); 3.13 (s, 2H).
Example 3
2-[4-(2,5-dichlorobenzenesulfonylamino)-phenyl]-N-hydroxy-acetamide (8)




Sulfonyl Chloride: 2,5-Dichlorobenzenesulfonyl chloride
Yield: Step 1: 66%
Yield: Step 2: 96%
Yield: Step 3: 66%
1H NMR (300 MHz, DMSO-d6); δ 10.68 (s, 1H), 8.88 (s, 1H), 7.95 (s, 1H), 7.67 (s, 2H); 7.13 (d, 2H, J=8 Hz), 7.02 (d, 2H, J=8 Hz), 3.16 (s, 2H)
Example 4
2-[4-(4-methylbenzenesulfonylamino)-phenyl]-N-hydroxy-acetamide (9)




Sulfonyl Chloride: 4-methylbenzenesulfonyl chloride
Step 1: Yield 100%
Step 2: 2-[4-(4-methylbenzenesulfonylamino)-phenyl]-N-hydroxy-acetamide (9)
Method B:
To a solution of methyl-2-[4-(4-methylbenzenesulfonylamino)]phenylacetate (459 mg, 1.44 mmol) in methanol (10 mL), at room temperature were added hydroxylamine hydrochloride (200 mg, 2.88 mmol) followed by sodium methoxide (389 mg, 7.19 mmol). The resulting mixture was heated overnight at 60° C. then treated with HCl (1N) until pH 2. The solvent was evaporated under reduced pressure then the aqueous phase was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) then evaporated. The crude mixture was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture yielding the title compound 9 (244 mg, 53%) as a white powder.
1H NMR (300 MHz, acetone-d6); δ 7.68 (d, J=8 Hz, 2H); 7.29 (d, J=8 Hz, 2H), 7.15 (br. s, 4H), 3.33 (s, 2H, CH2), 2.33 (s, 3H, CH3).
The following compounds were prepared following procedures analogous to those described in Example 1, step 1, and Example 4, step 2 (Method B), but substituting the sulfonyl chloride indicated for 2-benzothiophenesulfonyl chloride in step 1.
Example 5
2-[4-(3-trifluoromethylbenzenesulfonylamino)-phenyl]-N-hydroxy acetamide (10)




Sulfonyl Chloride: 3-trifluoromethylbenzenesulfonyl chloride
Yield: Step 1: 70%
Yield: Step 2: 49%
1H NMR (300 MHz, acetone-d6); δ=8.09 (s, 1H), 8.05 (d, 1H, J=8 Hz), 7.95 (d, 1H, J=8 Hz); 7.77 (t, 1H, J=8 Hz); 7.21 (d, 2H, J=8 Hz), 7.13 (d, 2H, J=8 Hz); 3.35 (s, 2H, CH2)
Example 6
2-[4-(tert-butylsulfonylamino)-phenyl]-N-hydroxy-acetamide (11)




Sulfonyl chloride: 4-tert-butylsulfonyl chloride
Yield: Step 1: 76%
Yield: Step 2: 40%
1H NMR (300 MHz, acetone-d6); δ 7.75 (d, 2H, J=9 Hz), 7.56 (d, 2H, J=9 Hz); 7.17 (s, 4H); 3.34 (s, 2H), 1.29 (s, 9H)
The following compound was prepared following procedures analogous to those described in Example 1, steps 1-2, substituting the sulfonyl chloride indicated for 2-benzothiophenesulfonyl chloride in step 1, followed by hydroxamic acid formation using
Method C
Example 7
2-[2-(naphthylsulfonylamino)-phenyl]-N-hydroxy-acetamide (12)




Sulfonyl Chloride: 2-naphthylsulfonyl chloride
Yield: Step 1: 100%
Yield: Step 2: 100%
Step 3: 2-[2-(naphthylsulfonylamino)-phenyl]-N-hydroxy-acetamide (12)
Method C:
To a solution of 2-[2-(naphthylsulfonylamino)]-phenylacetic acid (191 mg, 563 mmol) in CH2Cl2 (20 mL) at room temperature were added DMF (1 drop) followed by (COCl)2 (250 μL, 2.81 mmol). The mixture became yellow and solidification appeared. The reaction was stirred 90 min at room temperature then (COCl)2 was added until no bubbling ( ̃1 mL). Then the solvents were evaporated under reduced pressure. The crude material was dissolved in CH2Cl2 and TMSONH2 (3 mL) was added to the solution. The reaction was exothermic and the resulting mixture was stirred 2 h at room temperature then treated with HCl (1N) until pH 2. The phases were separated and the aqueous layer was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) then evaporated. The crude compound was purified 3 times by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture then another purification using preparative high pressure liquid chromatography using reversed phase chromatography with a gradient of water/CH3CN (10-70%) yielding the title compound 12 as a white powder (29 mg, 15%).
1H NMR (300 MHz, acetone-d6); δ 9.13 (s, 1H), 8.42 (s, 1H), 8.08-7.97 (m, 3H), 7.82 (dd, 1H, J=9 Hz, 1.5 Hz), 7.70-7.63 (m, 2H), 7.21-7.14 (m, 4H), 3.50 (s, 2H)
The following compound was prepared following procedures analogous to those described in Example 1, steps 1-2, substituting the indicated sulfonyl chloride and amine indicated for 2-benzothiophenesulfonyl chloride and 3 in step 1, followed by hydroxamic acid formation using Method D.
Example 8
N-hydroxy-[4-benzo[b]thiophene-2-sulfonylamino)-phenyl]-benzamide (13)




Sulfonyl Chloride: 2-Benzothiophenesulfonyl chloride
Amine: Methyl-4-aminobenzoate (2)
Yield: Step 1: 80%
Yield: Step 2: 69%
Step 3: N-hydroxy-[4-benzo[b]thiophene-2-sulfonylamino)-phenyl]-benzamide (13)
Method D:
To a solution of 2-[4-benzo[b]thiophene-2-sulfonylamino]benzoic acid (300 mg, 90 mmol) in DMF (20 mL) at room temperature were added 1-(3-dimethyl-aminopropyl)-3-ethylcarbodiimide hydrochloride (EDC, 207 mg, 1.08 mmol), and 1-Hydroxybenzotriazole hydrate (HOBT, 182 mg, 1.35 mmol). The mixture was stirred 20 min. at room temperature then NH2OTHP (158 mg, 1.35 mmol) was added. The resulting mixture was heated at 50° C. for 24 h then stirred at room temperature for 24 h. The DMF solvent was evaporated under reduced pressure and the residue was dissolved in CH2Cl2 and washed with brine or a saturated aqueous solution of NaHCO3. The combined organic extracts were dried over (MgSO4) then condensed. The crude compound was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture. The residue was then dissolved in methanol (20 mL) then 10-camphorsulfonic acid (CSA, 100 mg, 45 mmol) was added. The mixture was stirred 2 h at room temperature then the solvents were evaporated under reduced pressure at room temperature to avoid thermal decomposition. The crude was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture. A second purification was performed using a preparative high pressure liquid chromatography using a gradient of water/CH3CN (10-85%) as solvent giving the title compound 13 as a red solid (212 mg, 68%).
1H NMR (300 MHz, acetone-d6); δ 10.69 (s, 1H), 9.70 (s, 1H); 8.01-7.97 (m, 3H), 7.77 (d, 2H, J=9 Hz); 7.55-7.39 (m, 4H).
Example 9
2-[3-benzo[b]thiopene-2-sulfonylamino)-phenyl]N-hydroxy-acetamide (14)




Sulfonyl Chloride: 2-Benzothiophenesulfonyl chloride
Amine: Methyl-3-aminophenyl acetate (1)
Yield: Step 1: 88%
Yield: Step 2: 89%
Yield: Step 3: 32%
1H NMR (300 MHz, Acetoned6); δ 10.20 (s, 1H), 8.33 (s, 1H), 7.99-7.95 (m, 3H), 7.53-7.43 (m, 2H), 7.35 (s, 1H), 7.21-7.17 (m, 2H), 7.06-7.03 (m, 1H), 3.38 (s, 2H)
Example 10
2-[4-(3,4-dichlorobenzenesulfonylamino)-phenyl]-N-hydroxy-acetamide (15)




Sulfonyl Chloride: 3,4-Dichlorobenzenesulfonyl chloride
Yield: Step 1: 80%
Yield: Step 2: 67%
Yield: Step 3: 81%
1H NMR (300 MHz, acetone-d6); δ 10.12 (s, 1H), 9.15 (s, 1H), 7.92 (s, 1H), 7.74-7.71 (m, 2H), 7.23 (d, 2H, J=9 Hz), 7.14 (d, 2H, J=9 Hz), 3.36 (s, 2H)
Example 11
2-[4-(2-Thiophenesulfonylamino)-phenyl]-N-hydroxy-acetamide (16)




Sulfonyl Chloride: 2-Thiophenesulfonyl chloride
Yield: Step 1: 84%
Yield: Step 2: 83%
Yield: Step 3: 9%
1H NMR (300 MHz, acetone-d6); δ 7.78 (s, 1H), 7.53 (s, 1H), 7.21 (s, 4H), 7.09 (s, 1H), 3.37 (s, 2H)
Example 12
2-[4-(3-nitrobenzenesulfonylamino)-phenyl]-N-hydroxy-acetamide (17)




Sulfonyl Chloride: 3-Nitrobenzenesulfonyl Chloride
Yield: Step 1: 47%
Yield: Step 2: 34%
Yield: Step 3: 16%
1H NMR (300 MHz, acetone-d6); δ 9.31 (s, 1H), 8.59 (s, 1H), 8.45 (d, 1H, J=8 Hz), 8.16 (d, 1H, J=8 Hz), 7.85 (t, 1H, J=8 Hz), 7.20-7.14 (m, 4H), 3.35 (s, 2H)
Example 13
2-[4-(8-quinolinesulfonylamino)-phenyl]-N-hydroxy-acetamide (18)




Sulfonyl Chloride: 8-quinolinesulfonyl chloride
Yield: Step 1: 83%
Yield: Step 2: 78%
Yield: Step 3: 42%
1H NMR (300 MHz, acetone-d6); δ 9.17 (s, 1H), 8.50 (d, 1H, J=8 Hz), 8.33 (d, 1H, J=8 Hz), 8.21 (d, 1H, J=8 Hz), 7.71-7.68 (m, 3H), 7.05 (broad s., 4H), 3.22 (s, 2H)
Example 14
2-[4-(4-bromobenzenesulfonylamino)-phenyl]-N-hydroxy-acetamide (19)




Sulfonyl Chloride: 4-Bromobenzenesulfonyl chloride
Yield: Step 1: 80%
Yield: Step 2: 81%
Yield: Step 3: 48%
1H NMR (300 MHz, acetone-d6); δ 9.17 (s, 1H), 7.72 (s, 4H), 7.19-7.14 (m, 4H), 3.35 (s, 2H)
Example 15
N-Hydroxy-5-[3-benzenesulfonylamino)-phenyl]-pentanamide (26)




Step 1: 3-(benzenesulfonylamino)-phenyl iodide (21)

To a solution of 3-iodoaniline (5 g, 22.8 mmol), in CH2Cl2 (100 mL), were added at room temperature Et3N (6.97 mL) followed by benzenesulfonyl chloride (5.84 mL). The mixture was stirred 4 h then a white precipitate was formed. A saturated aqueous solution of NaHCO3 was added and the phases were separated. The aqueous layer was extracted several times with CH2Cl2 and the combined extracts were dried over (MgSO4) then evaporated. The crude mixture was dissolved in MeOH (100 mL) and NaOMe (6 g), was added and the mixture was heated 1 h at 60° C. The solution became clear with time and HCl (1N) was added. The solvent was evaporated under reduced pressure then the aqueous phase was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) and evaporated. The crude material was purified by flash chromatography using (100% CH2Cl2) as solvent yielding the title compound 21 (7.68 g, 94%) as yellow solid.
1H NMR: (300 MHz, CDCl3): δ 7.82-7.78 (m, 2H), 7.60-7.55 (m, 1H), 7.50-7.42 (m, 4H), 7.10-7.06 (m, 1H), 6.96 (t, J=8 Hz, 1H), 6.87 (broad s, 1H).
Step 2: 3-(benzenesulfonylamino)-phenyl-propargylic alcohol (22)
To a solution of 21 (500 mg, 1.39 mmol) in pyrrolidine (5 mL) at room temperature was added Pd(PPh3)4 (80 mg, 0.069 mmol), followed by CuI (26 mg, 0.139 mmol). The mixture was stirred until complete dissolution. Propargylic alcohol (162 μL, 2.78 mmol) was added and stirred 6 h at room temperature. Then the solution was treated with a saturated aqueous solution of NH4Cl and extracted several times with AcOEt. The combined organic extracts were dried over (MgSO4) then evaporated. The residue was purified by flash chromatography using hexane/AcOEt (1:1) as solvent mixture yielding 22 (395 mg, 99%) as yellow solid.
1H NMR: (300 MHz, CDCl3): δ 7.79-7.76 (m, 2H), 7.55-7.52 (m, 1H), 7.45 (t, J=8 Hz, 2H), 7.19-7.15 (m, 3H), 7.07-7.03 (m, 1H), 4.47 (s, 2H).
Step 3: 5-[3-(benzenesulfonylamino)-phenyl]-4-yn-2-pentenoate (23)
To a solution of 22 (2.75 g, 9.58 mmol) in CH3CN (150 mL) at room temperature were added 4-methylmorpholine N-oxide (NMO, 1.68 g, 14.37 mmol) followed by tetrapropylammonium perruthenate (TPAP, 336 mg, 958 mmol). The mixture was stirred at room temperature 3 h, and then filtrated through a Celite pad with a fritted glass funnel. To the filtrate carbethoxymethylenetriphenyl-phosphorane (6.66 g, 19.16 mmol) was added and the resulting solution was stirred 3 h at room temperature. The solvent was evaporated and the residue was dissolved in CH2Cl2 and washed with a saturated aqueous solution of NH4Cl. The aqueous layer was extracted several times with CH2Cl2 then the combined organic extract were dried over (MgSO4) and evaporated. The crude material was purified by flash chromatography using hexane/AcOEt (1:1) as solvent mixture giving 23 (1.21 g, 36%) as yellow oil.
1H NMR: (300 MHz, CDCl3): δ 7.81 (d, J=8 Hz, 2H), 7.56-7.43 (m, 3H), 7.26-7.21 (m, 3H), 7.13-7.11 (m, 1H), 6.93 (d, J=16 Hz, 1H), 6.29 (d, J=16 Hz, 1H), 4.24 (q, J=7 Hz, 2H), 1.31 (t, J=7 Hz, 3H).
Step 4: 5-[3-(benzenesulfonylamino)-phenyl]-4-yn-2-pentenic acid (24)
To a solution of 23 (888 mg, 2.50 mmol) in a solvent mixture of THF (10 mL) and water (10 mL) at room temperature was added LiOH (1.04 g, 25.01 mmol). The resulting mixture was heated 2 h at 60° C. and treated with HCl (1N) until pH 2. The phases were separated and the aqueous layer was extracted several times with AcOEt. The combined organic extracts were dried over (MgSO4) then evaporated. The crude residue was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture yielding 24 (712 mg, 88%), as white solid.
1H NMR: (300 MHz, DMSO-d6): δ 7.78-7.76 (m, 2H), 7.75-7.53 (m, 3H), 7.33-7.27 (m, 1H), 7.19-7.16 (m, 3H), 6.89 (d, J=16 Hz, 1H), 6.33 (d, J=16 Hz, 1H).
Step 5: 5-[3-(benzenesulfonylamino)-phenyl]-pentanoic acid (25)
To a solution 24 (100 mg, 306 mmol), in MeOH (6 mL) at room temperature was added a solution of Pd/C (10%, 20 mg, 1 mL MeOH). The reaction mixture was degassed and purged several times with H2 gas with a final pressure of 60 psi. The mixture was stirred 2 h at room temperature then the resulting solution was filtrated over a silica gel pad with a fritted glass funnel. The solvent was evaporated yielding 25 (68 mg, 96%) and it was used directly for the next step without further purification.
1H NMR: (300 MHz, acetone-d6): δ 7.81-7.78 (m, 2H), 7.56-7.46 (m, 3H), 7.11-7.01 (m, 3H), 6.87 (d, J=8 Hz, 1H), 2.49 (broad s, 2H), 2.25 (broad s, 2H), 1.52 (broad s, 4H)
Step 6: N-Hydroxy-5-[3-benzenesulfonylamino)-phenyl]-pentanamide (26)
To a solution of 25 (100 mg, 300 mmol) in DMF (10 mL) at room temperature were added 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDC, 69 mg, 320 mmol), and 1-hydroxybenzotriazole hydrate (HOBT, 61 mg, 45 mmol). The mixture was stirred 20 min. at room temperature then NH2OTHP (53 mg, 45 mmol) was added. The resulting mixture was heated overnight at 50° C. The DMF solvent was evaporated under reduced pressure and the residue was dissolved in CH2Cl2 and washed with brine or a saturated aqueous solution of NaHCO3. The combined organic extracts were dried over (MgSO4) then evaporated. The crude compound was purified by flash chromatography using hexane/acetone (7:3) as solvent mixture. The residue was then dissolved in MeOH (20 mL) then 10-camphorsulfonic acid (CSA, 35 mg, 150 mmol) was added. The mixture was stirred 2 h at room temperature then the solvents were evaporated under reduced pressure at room temperature to avoid thermal decomposition. The crude mixture was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture giving 26 as a yellowish solid (62 mg, 60%).
1H NMR: (300 MHz, acetone-d6): δ=7.80-7.78 (m, 2H), 7.56-7.52 (m, 3H), 7.13-6.89 (m, 4H), 2.52 (broad s, 2H), 2.10 (broad s, 2H), 1.53 (broad s, 4H)
Example 16
N-Hydroxy-5-[4-(benzenesulfonylamino)-phenyl]-4-yn-2-pentanamide (32)




Step 1: 4-(benzenesulfonylamino)-phenyl iodide (28)

Compound 28 was prepared using the procedure described in Example 15, step 1, but substituting 4-iodoaniline for 3-iodoaniline.
Yield: 97%
1H NMR: (300 MHz, CDCl3): δ 9.15 (broad s, 1H), 7.82 (d, J=8 Hz, 2H), 7.68-7.51 (m, 5H), 7.05 (d, J=8 Hz, 2H).
Step 2: 4-(benzenesulfonylamino)-phenyl-propargylic alcohol (29)
Compound 29 was prepared using the procedure described in Example 15, step 2 but substituting compound 21 for compound 28.
Yield: 61%
1H NMR: (300 MHz, acetone-d6): δ 7.83-7.80 (m, 2H), 7.62-7.51 (m, 3H), 7.30 (d, J=8 Hz, 2H), 7.21 (d, J=8 Hz, 2H), 4.36 (s, 2H), 2.80 (broad s, 2H).
Step 3: 5-[4-(benzenesulfonylamino)-phenyl]-4-yn-2-pentenoate (30)
Compound 30 was prepared using the procedure described in Example 15, step 3 but substituting compound 22 for compound 29
Yield: 16%
1H NMR: (300 MHz, CDCl3): δ 7.81-7.78 (m, 2H), 7.59-7.43 (m, 3H), 7.34 (d, J=8 Hz, 2H), 7.05 (d, J=8 Hz, 2H), 6.93 (d, J=16 Hz, 1H), 6.26 (d, J=16 Hz, 1H), 4.23 (q, J=7 Hz, 2H), 1.30 (t, J=7 Hz, 3H).
Step 4: 5-[4-(benzenesulfonylamino)-phenyl]-4-yn-2-pentenic acid (31)
Compound 31 was prepared using the procedure described in Example 15 step 4 but substituting compound 23 for compound 30
Yield: 92%
1H NMR: (300 MHz, acetone-d6): δ 7.87-7.84 (m, 2H), 7.62 (m, 3H), 7.42 (d, J=8 Hz, 2H), 7.28 (d, J=8 Hz, 2H), 6.94 (d, J=16 Hz, 1H), 6.29 (d, J=16 Hz, 1H).
Step 5: N-hydroxy-5-[4-(benzenesulfonylamino)-phenyl]-4-yn-2-pentanamide (32)
Compound 32 was prepared using the procedure described in Example 15 step 6 but substituting compound 25 for compound 31
Yield: 78%
1H NMR: (300 MHz, acetone-d6): δ 7.84 (broad s, 2H), 7.60-7.55 (m, 3H), 7.38-7.30 (m, 4H), 6.84 (d, J=16 Hz, 1H), 6.40 (d, J=16 Hz, 1H).
Example 17
N-Hydroxy-5-[4-benzenesulfonylamino)-phenyl]-pentanamide (34)
Step 1: 5-[4-(benzenesulfonylamino)-phenyl]-pentanoic acid (33)
Compound 33 was prepared using the procedure described in Example 15 step 5 but substituting compound 24 for compound 31.
Yield: 100%
1H NMR: (300 MHz, acetone-d6): δ=7.78-7.75 (m, 2H), 7.56-7.46 (m, 3H), 7.16-7.05 (m, 4H), 2.52 (broad s, 2H), 2.29-2.25 (m, 2H), 1.56 (broad s, 4H).
Step 2: N-Hydroxy-5-[4-benzenesulfonylamino)-phenyl]-pentanamide (34)
Compound 34 was prepared using the procedure described in Example 15 step 6 but substituting compound 25 for compound 33.
Yield: 62%
1H NMR: (300 MHz, acetone-d6): δ 7.78-7.75 (m, 2H), 7.59-7.51 (m, 3H), 7.09 (broad s, 4H), 2.85 (broad s, 1H), 2.53 (broad s, 2H), 2.05 (broad s, 2H), 1.56 (broad s, 4H).
Example 18
N-Hydroxy-3-[4-(benzenesulfonylamino)-phenyl]-2-propenamide (36)




Step 1: 3-[4-(benzenesulfonylamino)-phenyl]-2-propenoic acid (35)

To a solution of 28 (500 mg, 1.39 mmol), in DMF (10 mL) at room temperature were added tris(dibenzylideneacetone)dipalladium(0) (Pd2(dba)3; 38 mg, 1.67 mmol), tri-o-tolylphosphine (P(o-tol)3, 25 mg, 0.83 mmol), Et3N (483 μμL, 3.48 mmol) and finally acrylic acid (84 μμL, 1.67 mmol). The resulting solution was degassed and purged several times with N2 then heated overnight at 100° C. The solution was filtrated through a Celite pad with a fritted glass funnel then the filtrate was evaporated. The residue was purified by flash chromatography using CH2Cl2/MeOH (95:5) as solvent mixture yielding the title compound 35 (415 mg, 99%) as yellowish solid.
1H NMR: (300 MHz, acetone-d6): δ 7.88-7.85 (m, 2H), 7.62-7.55 (m, 6H), 7.29 (d, J=9 Hz, 2H), 6.41 (d, J=16 Hz, 1H), 2.95 (s, 1H), 2.79 (s, 1H).
Step 2: N-Hydroxy-3-[4-(benzenesulfonylamino)-phenyl]-2-propenamide (36)
To a solution of 35 (200 mg, 0.660 mmol) in DMF (10 mL) at room temperature were added 1-(3-Dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDCI, 151 mg, 0.79 mmol), and 1-Hydroxybenzotriazole hydrate (HOBT, 134 mg, 0.99 mmol). The mixture was stirred 20 min. at room temperature then NH2OTHP (116 mg, 0.99 mmol) was added. The resulting mixture was heated at 50° C. for 24 h then the DMF solvent was evaporated under reduced pressure and the residue was dissolved in CH2Cl2, washed with a saturated aqueous solution of NaHCO3. The combined organic extracts were dried over (MgSO4) then condensed. The crude compound was purified by flash chromatography using Hexane/acetone (7:3) as solvent mixture. The residue was then dissolved in MeOH (10 mL) then 10-camphorsulfonic acid (CSA, 77 mg, 0.33 mmol) was added. The mixture was stirred 2 h at room temperature then the solvents were evaporated under reduced pressure at room temperature to avoid thermal decomposition. The crude product was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture giving compound 36 (116 mg, 55%) as a orange solid.
1H NMR: (300 MHz, acetone-d6): δ 7.85-7.83 (m, 2H), 7.64-7.47 (m, 6H), 7.26 (d, J=8 Hz, 2H), 6.48 (m, 1H), 2.82 (s, 1H), 2.79 (s, 1H).
Example 19
N-Hydroxy-3-[4-(benzenesulfonylamino)-phenyl]-2-propanamide (38)
Step 1: 3-[4-(benzenesulfonylamino)-phenyl]-2-propionic acid (37)
To a solution of 35 (350 mg, 1.16 mmol) in MeOH (15 mL) at room temperature was added a solution of Pd/C 10% (50 mg. in MeOH  ̃3 mL). Then the resulting solution was purged several times with H2 with a final pressure of 60 psi. The solution was stirred 4 h then filtrated through a Celite pad with a fritted glass funnel. The filtrate was evaporated and the residue compound 37 was pure enough to use for the next step without further purification.
1H NMR: (300 MHz, acetone-d6): δ 8.92 (broad s, 1H), 7.79-7.76 (m, 2H), 7.60-7.47 (m, 3H), 7.12 (s, 4H), 3.32 (s, 1H), 2.81 (t, J=8 Hz, 2H), 2.53 (t, J=8 Hz, 2H).
Step 2: N-Hydroxy-3-[4-(benzenesulfonylamino)-phenyl]-2-propanamide (38)
To a solution of 37 (1.16 mmol) in DMF (10 mL) at room temperature were added 1-(3-Dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDC, 266 mg, 1.39 mmol), and 1-Hydroxybenzotriazole hydrate (HOBT, 235 mg, 1.74 mmol). The mixture was stirred 20 min. at room temperature then NH2OTHP (204 mg, 1.74 mmol) was added. The resulting mixture was heated at 50° C. for 24 h then the DMF solvent was condensed under reduced pressure and the residue was dissolved in CH2Cl2, washed with a saturated aqueous solution of NaHCO3. The combined organic extracts were dried over (MgSO4) then evaporated. The crude compound was purified by flash chromatography using Hexane/acetone (7:3) as solvent mixture. The residue was then dissolved in MeOH (10 mL) then 10-camphorsulfonic acid (CSA, 135 mg, 0.58 mmol) was added. The mixture was stirred 2 h at room temperature then the solvents were evaporated under reduced pressure at room temperature to avoid thermal decomposition. The crude was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture giving the title compound 38 (237 mg, 64%, for the last 3 steps) as a yellow solid.
1H NMR: (300 MHz, acetone-d6): δ 8.91 (broad s, 1H), 7.78-7.76 (m, 2H), 7.57-7.51 (m, 3H), 7.10 (broad s, 4H), 2.82 (broad s, 2H), 2.34 (broad s, 2H), 1.07 (s, 1H), 0.85 (s, 1H).
Example 20
N-Hydroxy-4-[4-(benzenesulfonylamino)-phenyl]-butanamide (42)




Step 1: Methyl-4-(4-aminophenyl)-butanoate (40)

To a solution of 4-(4-aminophenyl)-butyric acid (5 g, 27.90 mmol) in MeOH (100 mL) at room temperature was added HCl conc. (37% 15 mL). The resulting mixture was stirred overnight at 50° C. then treated with a saturated aqueous solution NaHCO3 and Na2CO3 solid until pH 9. The solvent was evaporated under reduced pressure then the aqueous phase was extracted several times with CH2Cl2. The crude material was purified by flash chromatography using CH2Cl2/MeOH as solvent mixture yielding 40 (4.93 g, 91%) as orange solid.
1H NMR: (300 MHz, acetone-d6): δ 6.89 (d, J=8 Hz, 2H), 6.59 (d, J=8 Hz, 2H), 4.40 (broad s, 1H), 3.60 (s, 3H), 2.48 (t, J=7 Hz, 2H), 2.28 (t, J=7 Hz, 2H), 1.82 (qt, J=7 Hz, 2H).
Step 2: 4-[4-(benzenesulfonylamino)-phenyl]-butyric acid (41)
To a solution of 40 (500 mg, 2.59 mmol) in CH2Cl2 at room temperature were added Et3N (901 μμL, 6.48 mmol) followed by benzenesulfonyl chloride (661 μL, 5.18 mmol). The mixture was stirred overnight at room temperature then treated with a saturated aqueous solution of NH4Cl. The phases were separated and the organic layer was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) then evaporated under reduced pressure. The residue was dissolved in a solvent mixture of THF (25 mL) and water (25 mL) then LiOH (1.08 g, 25.9 mmol) was added. The mixture was heated at 50° C. for 1 h then treated with HCl (1N) until pH2. The phases were separated and the aqueous layer was extracted several times with AcOEt. The combined organic extracts were dried over (MgSO4) then evaporated. The crude was purified by flash chromatography using CH2Cl2/MeOH (95:5) as solvent mixture yielding 41 (800 mg, 96%) as a white solid
1H NMR: (300 MHz, CDCl3): δ 8.82 (1H, s broad), 7.77-7.74 (2H, m), 7.55-50 (1H, m), 7.44-7.39 (2H, m), 7.05-6.97 (4H, m), 2.58 (2H, t, J=7 Hz), 2.31 (2H, t, J=7 Hz), 2.17 (1H, s), 1.94-1.84 (2H, m).
Step 3: N-Hydroxy-4-[4-(benzenesulfonylamino)-phenyl]-butanamide (42)
To a solution 41 (800 mg, 2.59 mmol) in DMF (20 mL) at room temperature were added 1-(3-Dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDC, 593 mg, 3.12 mmol), and 1-Hydroxybenzotriazole hydrate (HOBT, 524 mg, 3.89 mmol). The mixture was stirred 20 min. at room temperature then NH2OTHP (455 mg, 3.89 mmol) was added. The resulting mixture was heated at 50° C. for 24 h then the DMF solvent was evaporated under reduced pressure and the residue was dissolved in CH2Cl2, washed with a saturated aqueous solution of NaHCO3. The combined organic extracts were dried over (MgSO4) then evaporated. The crude compound was purified by flash chromatography using Hexane/acetone (7:3) as solvent mixture. The residue was then dissolved in MeOH (30 mL) then 10-camphorsulfonic acid (CSA, 300 mg, 1.30 mmol) was added. The mixture was stirred 2 h at 50° C. then the solvents were condensed under reduced pressure at room temperature to avoid thermal decomposition. The crude was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture giving the title compound 42 (115 mg, 13%) as a yellowish solid.
1H NMR: (300 MHz, CDCl3): δ 7.79-7.76 (m, 2H), 7.61-7.48 (m, 3H), 7.13-7.05 (m, 4H), 2.83 (broad s, 1H), 2.53 (t, J=7 Hz, 2H), 2.14-2.04 (m, 2H), 1.83 (t, J=7 Hz, 2H).
Example 21
N-Hydroxy-4-(3-oxo-3-phenylpropenyl)-benzamide (45)




Step 1: 4-(3-oxo-3-phenylpropenyl)-benzoic acid (43)

Sodium methoxide (1.8 g, 33.3 mmol) was added to a stirred suspension of 4-carboxybenzaldehyde (2.5 g, 16.6 mmol) and acetophenone (2.0 g uL, 16.6 mmol) in methanol (50 mL) at room temperature. The mixture was stirred at room temperature for 16 hours, and half of the volume of methanol was removed under reduced pressure. The mixture was poured into HCl 1M (50 mL) (until pH=2) and ethyl acetate was added. The separated aqueous layer was extracted with ethyl acetate (3×30 mL) dried (MgSO4 anh.), filtered and evaporated. The residue was triturated with dichloromethane-hexanes (1:1) to afford 3 g of 43 (72% yield).
1H NMR (300 MHz, CDCl3); δ 7.50-7.87 (m, 7H), 8.04 (d, 2H, J=8 Hz), 8.16 (d, 2H, J=8 Hz)
Step 2: 4-(3-oxo-3-phenylpropenyl)-N—(O-tetrahydropyranyl)-benzamide (44)
The carboxylic acid 43 (260 mg, 1.0 mmol) was dissolved in anhydrous CH2Cl2 (10 mL) and DCC (256 mg, 1.2 mmol) followed by NH2OTHP (145 mg, 1.2 mmol) were added. The mixture was allowed to stir at room temperature for 2 h. Added NH4Cl sat. and extracted with EtOAc. The organic layer was dried over MgSO4, filtered and the solvent was evaporated under vacuum. (Purification by column chromatography using 1% MeOH/CH2Cl2 give the title compound which was used directly in the next step.
Step 3: N-Hydroxy-4-(3-oxo-3-phenylpropenyl)-benzamide (45)
The protected hydroxamic acid 44 (234 mg, 0.67 mmol) was dissolved in MeOH (7 mL) then CSA (31 mg, 0.13 mmol) was added. The mixture was allowed to stir at reflux for 2 hours or until the reaction was complete by TLC. Added HCl 1N, extracted with EtOAc, dried the organic layer over anhydrous MgSO4 and filtered. The solvent was evaporated under vacuum. Purification by column chromatography using 5% MeOH/CH2Cl2, gave the title compound.
1H NMR (300 MHz, DMSO-d6), δ 7.53-8.20 (m, 11H); 9.12 (br. s, 1H); 11.35 (br. s, 1H)
Example 22
N-Hydroxy-4-(3-oxo-3-phenylpropyl)-benzamide (50)




Step 1: Methyl-4-(3-oxo-3-phenylpropenyl)-benzoate (46)

To 4-carbomethoxybenzaldehyde (79 mg, 0.48 mmol) and acetophenone (56 L, 0.48 mmol) in anhydrous methanol (1.6 mL), was added neat sodium methoxide (26 mg, 0.48 mmol). The mixture was stirred at room temperature overnight then heated to reflux for 1 hour, cooled down to room temperature and added HCl 1N and EtOAc. The layers were separated and the organic layer dried over anhydrous MgSO4 and filtered. The solvent was evaporated under vacuum to afford a yellow solid, which was recrystallized from acetonitrile/water to give a pale yellow crystalline solid.
1H NMR (300 MHz, CDCl3); δ 3.95 (s, 3H), 7.50-8.12 (m, 11H)
Step 2: Methyl-4-(3-oxo-3-phenylpropyl)-benzoate (47)
The aromatic enone 46 (321 mg, 1.20 mmol) was dissolved in anhydrous THF (6 mL) and anhydrous MeOH (6 ml). Added 2 small scoops of Pd 10% on activated C, placed under an atmosphere of hydrogen and allowed to stir for 2 hours at room temperature. Purged with nitrogen, filtered through Celite and removed solvent by evaporation under vacuum. The benzylic alcohol is reoxidized to the ketone by the following procedure. The crude was taken back in anhydrous CH2Cl2 (10 mL), with 3 Å molecular sieves, TPAP (1 scoop) was added followed by NMO (212 mg, 1.8 mmol). Stirred at room temperature for 30 minutes and filtered through a plug of silica gel. Solvent was evaporated under vacuum and purified by column chromatography using 10% EtOAc/Hexane.
1H NMR (300 MHz, CDCl3); δ 3.14 (t, 2H), 3.34 (t, 2H), 3.90 (s, 3H), 7.30-7.60 (m, 6H), 7.92-7.99 (m, 4H).
Step 3: 4-(3-oxo-3-phenylpropyl)-benzoic acid (48)
To a solution of methyl ester 47 (195 mg, 0.73 mmol) in water/THF (1:1, 0.07M) was added LiOH (46 mg, 1.1 mmol). The resulting solution was stirred overnight at room temperature or until no starting material was detected by TLC. HCl 1N was added and the solution was extracted with EtOAc and the organic layer was dried over anhydrous MgSO4. Filtration and evaporation of the solvent under vacuum followed by purification by column chromatography using 10% MeOH/CH2Cl2, gave the title compound.
1H NMR (300 MHz, CDCl3); δ 3.16 (t, 2H), 3.36 (t, 2H), 7.33-7.60 (m, 5H), 7.93-8.06 (m, 4H).
Step 4: N-hydroxy-4-(3-oxo-3-phenylpropyl)-benzamide (50)
Following the procedure described in Example 21, Steps 2-3, but substituting compound 48 for carboxylic acid 4, the title compound was obtained.
1H NMR (300 MHz, DMSO-d6); δ 2.97 (t, 2H), 3.38 (t, 2H), 7.34 (d, 2H, J=8 Hz), 7.45-7.70 (m, 5H), 7.96 (dd, 2H, J=8 Hz, 1 Hz), 11.14 (br. s, 1H)
Example 23
N-Hydroxy-4-(3-oxo-3-phenyl-1-hydroxypropyl)-benzamide (53)




Step 1: 4-Carboxy-N—(O-tetrahydropyranyl)-benzamide (51)

Hydroxylamine-O-THP (3.9 g, 33.2 mmol) was added to a suspension of 4-formylbenzoic acid (4.2 g, 27.7 mmol) and DCC (6.8 g, 33.2 mmol) in dichloromethane (200 mL). The mixture was stirred at room temperature overnight and quenched with saturated ammonium chloride. The separated aqueous layer was extracted with ethyl acetate (3×100 ml) and the combined organic layers were washed with brine, dried (MgSO4 anh), filtered and evaporated. Flash chromatography of the residue (10% methanol in CH2Cl2), afforded (51).
1H NMR (300 MHz, CDCl3); δ ppm. 10.04 (s, 1H), 8.95 (s, 1H), 7.99 (d, 2H, J=7.0 Hz), 7.93 (d, 2H, J=7.0 Hz), 5.1 (s, 1H), 3.60 (m, 2H), 1.60 (m, 6H)
Step 2: 4-(3-oxo-3-phenyl-1-hydroxypropyl)-N—(O-tetrahydropyranyl)-benzamide (52)
n-BuLi (1.4M/hexane, 1.6 mL, 2.2 mmol) was added to a 0° C. solution of diisopropylamine (337 μL, 2.4 mmol) in anhydrous THF (15 mL). Stirred at 0° C. 10 minutes, then cooled to −78° C. Added acetophenone, then stirred 30 minutes at −78° C. Cannulated into a −78° C. solution of the aldehyde 9 (50 mg, 2.0 mmol) in anhydrous THF (10 mL). Stirred 3 hours at −78° C., then added NH4Cl. Warmed to room temperature, extracted with EtOAc, dried over MgSO4, filtered and evaporated solvent under vacuum. Purification by HPLC CH3CN:H2O: TFA 0.1%; 10-95% gave the title compound 52.
Step 3: N-Hydroxy-4-(3-oxo-3-phenyl-1-hydroxypropyl)-benzamide (53)
Following the same procedure as described in Example 21, Step 3, but substituting compound 52 for compound 44, the title compound was obtained.
1H NMR (300 MHz, DMSO-d6); δ 3.20 (dd, 1H, J=4 Hz, J=16 Hz), 3.42 (dd, 1H=16 Hz, 8 Hz), 5.20 (m, 1H), 7.44-8.18 (m, 9H), 11.15 (br. s, 1H), 11.32 (br. s, 1H)
Example 24
N-Hydroxy-4-(3-phenylpropyl)-benzamide (56)




Step 1: 4-(3-phenylpropenyl)-benzoic acid/4-(3-phenyl-2-propenyl)-benzoic acid (54)

Allylbenzene (255 μμL, 1.9 mmol), 4-bromobenzoic acid (523 mg, 2.6 mmol), Et3N (0.91 mL, 6.5 mmol), Palladium (II) Acetate (16 mg, 0.052 mmol), triphenylphosphine (60 mg, 0.21 mmol) and acetonitrile (5 mL) were stirred at reflux overnight in a round bottom flask. Added HCl 1N, extracted with EtOAc, dried the organic layer on anhydrous MgSO4, filtered, evaporated solvent under vacuum. Purified by column chromatography using 10% MeOH/CH2Cl2 yielded 90 mg (14%) of mixture of two regioisomers 54. The mixture was then submitted for hydrogenation without further characterization.
Step 2: 4-(3-phenylpropyl)-benzoic acid (55)
A mixture of regioisomeric olefins 54 (100 mg, 0.42 mmol) and Pd 10% on C (10 mg) in methanol (4 mL) was vigorously stirred under H2 atmosphere (14 psi). The mixture was stirred for 2 hours at room temperature, filtered through Celite and evaporated to afford 55 as an oil. Flash chromatography of the residue gave 55 (88 mg, 88%).
1H NMR (300 MHz, CDCl3); δ ppm 8.10 (d, 2H, J=8.0 Hz), 7.35 (m, 7H), 2.73 (m, 4H), 2.00 (m, 2H)
Step 3: N-Hydroxy-4-(3-phenylpropyl)-benzamide (56)
Following the same procedure as described in Example 21, Steps 2-3, but substituting compound 55 for compound 43, the title compound was obtained as a beige solid. (24 mg, 26% yield)
1H NMR (300 MHz, CD3OD); δ (ppm) 7.63 (d, 2H, J=8.0 Hz); 7.38-7.05 (m, 7H), 2.63 (m, 4H), 1.91 (m, 2H)
Example 25
N-Hydroxy-4-(4-phenylbutyl)-benzamide (61)




Step 1: 4-(1-butenyl-4-phenyl)-benzoic acid/4-(2-butenyl-4-phenyl)-benzoic acid (57/58)

Under nitrogen atmosphere in a 25 mL round bottomed flask were mixed: 4-phenyl-1-butene (568 μL, 3.8 mmol), 4-bromobenzoic acid (634 mg, 3.2 mmol), tris(dibenzylideneacetone)dipalladium(0) (87 mg, 0.1 mmol), tri-o-tolylphosphine (58 mg, 0.2 mmol), triethylamine (1.1 mL, 7.9 mmol) in N,N-dimethylformamide (7 mL, 0.5 M solution). The mixture was stirred for 22 hours at 100° C. Then, the resulting suspension was cooled to room temperature, filtered through Celite and rinsed with ethyl acetate. The filtrate was acidified with 1N HCl, the phases were separated and the aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with water, brine, dried over MgSO4, filtered and concentrated. The resulting solid was triturated with hexane:dichloromethane (9:1) to give 367 mg (46%) of beige solid 57/58.
1H NMR (300 MHz, (CD3)2CO): δ (ppm) 2.50-2.60 (m, 2H), 2.80 (t, 2H, J=9.0 Hz), 6.40-6.50 (m, 2H), 7.12-7.35 (m, 5H), 7.41 (d, 2H, J=9.0 Hz), 7.92 (d, 2H, J=9.0 Hz).
Step 2: 4-(4-phenylbutyl)-benzoic acid (59)
Following the procedure described in Example 24, Step 2, but substituting compound 57/58 for compounds 54, the title compound was obtained as a white solid in 92% yield.
1H NMR (300 MHz, CD3OD); δ (ppm) 1.60-1.75 (m, 4H), 2.65 (t, 2H, J=9.0 Hz), 2.72 (t, 2H, J=9.0 Hz), 7.12-7.30 (m, 5H), 7.33 (d, 2H, J=9.0 Hz), 7.96 (d, 2H, J=9.0 Hz)
Step 3: 4-(4-phenylbutyl)-N—(O-tetrahydropyranyl)-benzamide (60)
Under nitrogen atmosphere in a 25 mL round bottomed flask, to 4-(4-phenylbutyl)benzoic acid 59 (341 mg, 1.3 mmol) in 5 mL of N,N-dimethylformamide (0.3 M solution) was added the 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (308 mg, 1.6 mmol) and the 1-hydroxybenzotriazole hydrate (272 mg, 2.0 mmol) at room temperature. The mixture was stirred for 30 minutes then, the 2-(tetrahydropyranyl)hydroxylamine (235 mg, 2.0 mmol) was added and the mixture was stirred for 4 days. The N,N-dimethylformamide was removed under vacuum, the resulting oil was dissolved in ethyl acetate, washed with water and brine, dried over MgSO4, filtered and concentrated to give 95% yield of crude title compound 60.
1H NMR (300 MHz, CD3OD); δ (ppm) 1.50-1.75 (m, 10H), 2.65 (t, 2H, J=9.0 Hz), 2.72 (t, 2H, J=9.0 Hz), 3.51 (d, 1H, J=15 Hz), 4.05 (t, 1H, J=15 Hz), 5.05 (s, 1H), 7.10-7.35 (m, 7H), 7.75 (d, 2H, J=9.0 Hz), 10.60 (s, 1H)
Step 4: N-Hydroxy-4-(4-phenylbutyl)-benzamide (61)
Under nitrogen atmosphere, to the crude oil in a 25 mL round bottomed flask, were added 5 mL of methyl alcohol (0.3 M solution) and camphorsulfonic acid (333 mg, 1.4 mmol). The mixture was stirred for 2 hours at room temperature. The methyl alcohol was removed under vacuum without heating and the resulting oil was purified by flash chromatography eluting methyl alcohol and dichloromethane (1:19). The solid was with hexane:dichloromethane (9:1) to give 212 mg (59%) of beige solid 61.
1H NMR (300 MHz, (CD3)2CO): δ 1.66 (m, 4H), 2.65 (t, 2H, J=7.2 Hz), 2.70 (t, 2H, J=7.1 Hz), 7.15-7.31 (m, 7H), 7.75 (d, 2H, J=7.8 Hz), 8.18 (broad s, 1H), 10.68 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 31.6 (t), 31.8 (t), 36.1 (t), 36.2 (t), 2×126.4 (d), 127.8 (d), 2×129.1 (d), 2×129.2 (d), 2×129.3 (d), 130.6 (s), 143.3 (s), 147.3 (s), 165.9 (s).
Example 26
N-Hydroxy-3-(3-phenylpropyl)-benzamide (64)
Step 1: 3-(3-phenylpropenyl)-benzoic acid (62)
Following the same procedure as described in Example 24, step 1, but substituting 4-bromobenzoic acid for 3-bromobenzoic acid, the title compound was obtained as mixture of olefins. The mixture was submitted to the next step without purification.
1H NMR (300 MHz, CDCl3); δ (ppm); 3.6 (dd, 2H, CH2); 6.4 (dd, 2H, vinylic); 7.0-7.5 (m, 8H, CHAr); 8.0 (s, 1H, CHAr)
Step 2: 3-(3-phenylpropyl)-benzoic acid (63)
Following the same procedure as described in Example 24, Step 2, but substituting compound 62 for compound 54, the title compound was obtained in 52% yield and submitted to the next step without further purification.
1H NMR (300 MHz, CDCl3); δ (ppm); 2.0 (m, 2H, CH2); 2.7 (m, 4H, 2CH2); 7.0-7.4 (m, 8H, CHAr); 8.0 (s, 1H, CHAr)
Step 3: N-Hydroxy-3-(3-phenylpropyl)-benzamide (64)
Following the procedure described in Example 25, Step 3-4, but substituting compound 63 for compound 59, the title compound was obtained. Purification by flash chromatography using CH2Cl2:MeOH (9.5:0.5) gave compound 64 in 20% yield.
1H NMR (300 MHz, DMSO-d6); δ 1.8 (m, 2H, CH2); 2.8 (m, 4H, CH2); 7.0-7.4 (m, 7H, CHAr); 7.6 (s, CHAr); 9.0 (s, NH); 11.2 (s, OH)
Example 27
N-Hydroxy-3-(2-phenylethyl)-benzamide (68)




Step 1: 3-(2-phenylethenyl)-benzoic acid (65/66)

A 1.0 M solution of lithium bis(trimethylsilyl) amide (3.3 mL, 3.3 mmol) in THF was added to a stirred suspension of benzyltriphenylphosphonium bromide (1.44 g, 3.6 mmol) in THF (35 mL) at 0° C. The resulting orange solution was added via cannula to a mixture of 3-carboxybenzaldehyde (500 mg, 3.3 mmol) and lithium bis(trimethylsilyl)amide (3.3 mL, 3.3 mmol) in THF (10 mL). The mixture was stirred overnight at room temperature. A 1N solution of HCl (75 mL) and ethyl acetate (75 mL) were added and the separated aqueous layer was extracted with ethyl acetate (3×50 mL), dried (MgSO4 anh.) filtered and evaporated. The residue was purified by HPLC (10:95 CH3CN:H2O, TFA 0.1%) to afford 130 mg of the title compound (17%)
1H NMR (300 MHz, CDCl3); δ (ppm) (1:1) E:Z mixture 8.22 (s, 1H), 7.98 (s, 1H), 7.90-7.10 (m, 16H), 6.70 (d, 1H, J=15.0 Hz), 6.62 (d, 1H, J=15.0 Hz)
Step 2: 3-(2-phenylethyl)-benzoic acid (67)
Following the same procedure as described in Example 24, Step 2, but substituting compounds 65/66 for compound 54, the title compound was obtained quantitatively.
1H NMR (300 MHz, CDCl3); δ (ppm) 2.98 (m, 4H); 7.30 (m, 7H); 7.99 (m, 2H)
Step 3: N-Hydroxy-3-(2-phenylethyl)-benzamide (68)
Following the same procedure as described in Example 25, Step 3 and 4, but substituting compound 67 for compound 59, the title compound was obtained in 22% yield.
1H NMR (300 MHz, DMSO-d6); δ (ppm) 2.82 (s, 4H); 7.03-7.08 (m, 8H); 7.62 (s, 1H); 8.98 (br. s, 1H); 11.15 (br. s, 1H)
Example 28
N-Hydroxy-4-(2-thiophenyl)-ethyl benzamide (70)




Step 1: 4-(2-thiophenyl)-ethyl benzoic acid (69)

According to the published procedure (Gareau et al., Tet. Lett., 1994, 1837), under nitrogen atmosphere in a 50 mL round bottomed flask containing 4-vinylbenzoic acid (1.0 g, 6.75 mmoles) in 10 mL of benzene (0.7 M) was added benzenethiol (797 μL, 7.76 mmoles) followed by VAZOTM (Aldrich Chemical Company, 495 mg, 2.02 mmoles). The mixture was stirred for 12 hours at reflux. The resulting solution was cooled at room temperature and the solvent was evaporated under vacuo. The solid was purified by trituration using hexane and dichloromethane to afford 1.94 g (85%) of white solid.
1H NMR (300 MHz, CDCl3): δ 3.01 (t, 2H, J=8.4 Hz), 3.28 (dd, 2H, J=7.2, 7.8 Hz), 7.21 (tt, 1H, J=1.2, 7.2 Hz), 7.34 (t, 2H, J=8.1 Hz), 7.38-7.43 (m, 1H), 7.41 (d, 2H, J=8.4 Hz), 7.97 (d, 2H, J=8.1 Hz).
Step 2: N-Hydroxy-4-(2-thiophenyl)-ethyl benzamide (70)
Under nitrogen atmosphere in a 50 mL round bottomed flask containing 4-(2-thiophenyl)-ethyl benzoic acid (600 mg, 2.32 mmoles) in 12 mL of N,N-dimethyl-formamide (0.2 M) was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (579 mg, 3.02 mmoles) and 1-hydroxybenzotriazole hydrate (377 mg, 2.79 mmoles) at room temperature. The mixture was stirred 30 minutes then, hydroxylamine hydrochloride (242 mg, 3.48 mmoles) and triethylamine (971 μL, 6.97 mmoles) was added and the mixture was stirred for 12 hours at 50° C. The N,N-dimethylformamide was removed under vacuo and the resulting oil was dissolved in ethyl acetate, washed with water, saturated sodium hydrogen carbonate solution, water and brine. The organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under vacuo. The crude solid was purified by trituration using hexane and dichloromethane to afford 450 mg (71%) of a beige solid.
RP-HPLC (Hewlett-Packard 1100, column C18 HP 4.6×250 mm, flow 1 mL/min, 10-95% CH3CN/H2O in 42 min with 0.1% TFA); Purity: 95.8% (220 nm), 93.2% (254 nm).
1H NMR (300.072 MHz, (CD3)2CO): δ 2.98 (t, 2H, J=7.2 Hz), 3.26 (dd, 2H, J=6.6, 8.4 Hz), 7.21 (tt, 1H, J=1.5, 6.9 Hz), 7.31-7.42 (m, 6H), 7.77 (d, 2H, J=9.3 Hz), 8.08 (broad s, 1H), 10.69 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 34.8 (t), 35.9 (t), 126.7 (d), 127.9 (d), 2×129.6 (d), 2×129.7 (d), 2×129.9 (d), 131.3 (s), 137.3 (s), 145.0 (s).
Elemental Analysis; Calc for C15H15O2NS X 0.1H2O: % C=75.31, % H=7.14, % N=5.17. Found: % C=75.2±0.1, % H=7.41±0.07, % N=5.17±0.01.
N-Hydroxy-4-(2-benzenesulfonyl)-ethyl benzamide (73)
Step 1: 4-(2-benzenesulfonyl)-ethyl benzoic acid (72)
Under nitrogen atmosphere in a 100 mL round bottomed flask containing 4-(2-thiophenyl)-ethyl benzoic acid (69) (600 mg, 2.32 mmoles) in 20 mL of dichloromethane (0.1 M) at 0° C. was added portionwise 3-chloroperbenzoic acid (Aldrich Chemical Co., 57-86% pure solid by, 2 g, 6.97 mmoles), as described by Nicolaou et al., J. Am. Chem. Soc., 114: 8897 (1992). The mixture was allowed to reach room temperature and was stirred for 1 hour. Dimethyl sulfide (5 mL) was added, the mixture was diluted in dichloromethane and washed 3 times with water. The organic layer was dried over anhydrous magnesium sulfate, filtered and the solvent were evaporated in vacuo to afford 3 g of white solid. This mixture of 3-chlorobenzoic acid and the desired 4-(2-benzenesulfonyl)-ethyl benzoic acid was placed in a 125 mL Erlenmeyer flask, dissolved in 30 mL of dichloromethane and treated with an excess of freshly prepared diazomethane solution in diethyl ether (0.35 M). Nitrogen was bubbled to removed the excess of diazomethane and solvents were evaporated under vacuum. The resulting solid was purified by flash chromatography, eluting with 20% ethyl acetate: 80% hexane to afford 341.6 mg (48%) of the corresponding ester. Saponification of this ester was done using the same procedure as described in Example 1, step 2, to afford 312.4 mg (96%) of 4-(2-benzenesulfonyl)-ethyl benzoic acid (72)
1H NMR (300 MHz, CDCl3): δ 3.06-3.11 (m, 2H), 3.56-3.61 (m, 2H), 7.37 (d, 2H, J=8.4 Hz), 7.67 (tt, 2H, J=1.5, 7.2 Hz), 7.76 (tt, 1H, J=1.2, 7.5 Hz), 7.93 (d, 2H, J=8.7 Hz), 7.97 (dd, 2H, J=1.8, 6.9 Hz).
Step 2: N-Hydroxy-4-(2-benzenesulfonyl)-ethyl benzamide (73)
Following the procedure described for N-hydroxy-4-(2-thiophenyl)-ethyl benzamide, but substituting 4-(2-benzenesulfonyl)-ethyl benzoic acid for 4-(2-thiophenyl)-ethyl benzoic acid, the title compound was obtained as a beige solid.
RP-HPLC (Hewlett-Packard 1100, column C18 HP 4.6×250 mm, flow 1 mL/min, 10-95% CH3CN/H2O in 42 min with 0.1% TFA); Purity: 98.8% (220 nm), 97.6% (254 nm).
1H NMR (300.072 MHz, (CD3)2CO): δ 2.98 (t, 2H, J=7.2 Hz), 3.26 (dd, 2H, J=6.6, 8.4 Hz), 7.21 (tt, 1H, J=1.5, 6.9 Hz), 7.31-7.42 (m, 6H), 7.77 (d, 2H, J=9.3 Hz), 8.08 (broad s, 1H), 10.69 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 25.2 (t), 34.3 (t), 55.6 (t), 128.0 (d), 2×128.8 (d), 129.4 (d), 2×130.2 (d), 131.1 (s), 134.5 (d), 140.7 (s), 145.5 (s), 165.8 (s).
N-Hydroxy-4-(2-benzenesulfoxide)-ethyl benzamide (71)
According to the procedure described by Van Der Borght et al., J. Org. Chem., 65: 288 (2000), under a nitrogen atmosphere in a 10 mL round bottomed flask containing N-hydroxy-4-(2-thiophenyl)-ethyl benzamide (70) (50 mg, 0.18 mmol) in 2 mL of methanol (0.1 M) was added tellurium dioxide (3 mg, 0.018 mmol) followed by a solution 35% in water of hydrogen peroxide (32 μL, 0.36 mmol). The mixture was stirred for five days and then brine was added. The aqueous layer was extracted 3 times with ethyl acetate and the combined organic layers were dried over anhydrous magnesium sulfate, filtered and the solvent were evaporated under vacuo. The resulting solid (43.3 mg) was purified by trituration using acetonitrile to afford 10 mg (20%) of beige solid.
RP-HPLC (Hewlett-Packard 1100, column C18 HP 4.6×250 mm, flow 1 mL/min, 10-95% CH3CN/H2O in 42 min with 0.1% TFA); Purity: 98.8% (220 nm), 97.9% (254 nm).
1H NMR (300.072 MHz, (CD3)2CO): δ 2.76-2.91 (m, 1H), 3.00-3.29 (m, 3H), 7.34 (d, 2H, J=8.4 Hz), 7.55-7.62 (m, 3H), 7.70 (dd, 2H, J=1.5, 8.1 Hz), 7.76 (d, 2H, J=8.1 Hz), 8.08 (broad s, 1H), 10.70 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 28.3 (t), 57.8 (t), 2×124.8 (d), 128.0 (d), 2×129.6 (d), 2×130.0 (d), 131.5 (d), 144.1 (s), 145.7 (s).
Example 29
N-Hydroxy-3-[4-(3-phenylpropyl)-phenyl]-propanamide (77)




Step 1: 3-(4-bromophenyl)-propanoic acid (74)

Under nitrogen atmosphere in a 250 mL round bottomed flask containing 4-bromocinnamic acid (5.0 g, 22 mmoles) in 45 mL of N,N-dimethylformamide (0.5 M) was added benzenesulfonylhydrazide (7.6 g, 44 mmoles). The mixture was stirred at reflux for 12 hours. The solution was cooled at room temperature, aqueous saturated ammonium chloride was added and the aqueous layer was extracted with ethyl acetate 3 times. Combined organic layers were washed with water and brine, dried over anhydrous magnesium sulfate, filtered and concentrated under vacuo. The resulting solid was purified by flash chromatography eluting with 5% methanol: 95% dichloromethane to afford 3.66 g (73%) of beige solid.
1H NMR (300 MHz, CDCl3): δ 2.66 (t, 2H, J=7.5 Hz), 2.91 (d, 2H, J=7.5 Hz), 7.08 (d, 2H, J=8.4 Hz), 7.41 (d, 2H, J=8.4 Hz).
Step 2: N-Hydroxy-3-(4-bromophenyl)-propanamide (75)
Following a procedure analogous to that described for the preparation of 70, 1.54 g (39%) of the title compound was obtained.
1H NMR (300 MHz, CDCl3): δ 2.39 (t, 2H, J=7.8 Hz), 2.89 (d, 2H, J=7.2 Hz), 7.18 (d, 2H, J=8.1 Hz), 7.42 (d, 2H, J=8.7 Hz), 8.18 (broad s, 1H), 9.98 (broad s, 1H).
Step 3: N-Hydroxy-3-[4-(3-phenyl-1-propenyl)-phenyl]-propanamide and N-Hydroxy-3-[4-(3-phenyl-2-propenyl)-phenyl]-propanamide (76)
Following a procedure analogous to that described in Example 25, step 1, but substituting N-hydroxy-3-(4-bromophenyl)-propanamide (75) (250 mg, 1.02 mmol) for 4-bromobenzoic acid and allyl benzene (163 μL, 1.2 mmol) for 4-phenyl-1-butene, to yield 155.4 mg (54%) of the mixed title compounds.
1H NMR (300 MHz, CDCl3): δ 2.39 (m, 2H), 2.88 (t, 2H, J=8.4 Hz), 3.51 (t, 2H, J=8.1 Hz), 6.32-6.53 (m, 2H), 7.14-7.44 (m, 9H), 8.60 (broad s, 1H), 10.04 (broad s, 1H).
Step 4: N-Hydroxy-3[4-(3-phenylpropyl)-phenyl]-propanamide (77)
Following a procedure analogous to that described in Example 24, step 2, but substituting the mixture of N-hydroxy-3-[4-(3-phenyl-1-propenyl)-phenyl]-propanamide and N-hydroxy-3-[4-(3-phenyl-2-propenyl)-phenyl]-propanamide (155 mg, 0.55 mmol) for olefins 54, 155.4 mg (99%) of the title compound was obtained.
RP-HPLC: (Hewlett-Packard 1100, column C18 HP 4.6×250 mm, flow 1 mL/min, 10-95% CH3CN/H2O in 42 min with 0.1% TFA); Purity: 99.9% (220 nm) (2 peaks but same compound proven by LCMS, 99.9% (254 nm). 1H NMR (300.072 MHz, (CD3)2CO): δ 1.91 (quintuplet, 2H, J=8.1 Hz), 2.38 (t, 2H, J=7.8 Hz), 2.61 (q, 4H, J=9.6 Hz), 2.87 (t, 2H, J=7.2 Hz), 7.12-7.29 (m, 9H), 8.42 (broad s, 1H), 10.01 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 26.3 (t), 28.7 (t), 29.8 (t), 30.3 (t), 30.7 (t), 121.1 (d), 3×123.7 (d), 3×123.8 (d), 133.9 (s), 133.4 (s), 137.8 (s), 164.9 (s).
Elemental Analysis; Calc for C18H21O2N X 0.1H2O: % C=75.81, % H=7.49, % N=4.91. Found: % C=75.7±0.3, % H=7.54±0.02, % N=4.85±0.03.
Example 30




Step 1: Ethyl 3-(4-nitrophenyl)-2-isopropyl propanoate (78)

To a precooled solution of diisopropylamine (34.7 mmol) in THF (30 mL) under nitrogen was added dropwise a 1.0 M solution of n-butyllithium (33.3 mmol). The resulting light yellow solution was stirred at −78° C. over 30 minutes and transferred via canula to a precooled (−78° C.) solution of ethyl isovalerate (34.7 mmol) in THF (50 mL). The mixture was stirred at −78° C. over 1 hour and a 4-nitrobenzyl bromide (13.9 mmol) solution in THF (20 mL) at room temperature was transferred dropwise via canula to the enolate solution which turned deep red. The mixture was stirred over 15 minutes and the reaction was quenched with aqueous saturated ammonium chloride solution (NH4Cl). The mixture was allowed to warm to room temperature over 1 hour and turned brown upon warming. It was poured into a large volume of saturated NH4Cl solution and the layers were separated. The aqueous layer was extracted twice with diethyl ether and the combined organic layers were washed with brine, dried over magnesium sulfate and concentrated in vacuo. The residue was purified by flash chromatography on silica gel using ethyl acetate and hexanes (10:90) as the eluent, yielding 73% of the pure title compound 78 as a light yellow oil.
Step 2: Ethyl 3-(4-aminophenyl), 2-isopropyl propanoate (79)
To a hydrogen flushed (vacuum/H2, 3 times) solution of 1 (1.88 mmol) in methanol (10 mL) was added 10% palladium on charcoal (0.018 mmol) previously quenched with methanol in a separate flask. The black heterogeneous resulting mixture was stirred at room temperature under hydrogen atmosphere (1 atm) over 20 hours. The hydrogen was then evacuated by vacuum and replaced with air. Then, the mixture was filtered through celite, rinsing with methanol while making sure the pad never gets dry. The filtrate was concentrated to a red oil. The residue was purified by flash chromatography on silica gel using ethyl acetate and hexanes (30:70) as the eluent, yielding 73% of the pure title compound 79 as a light red oil.
Steps 3-5: (81)
Compound 79 was coupled with benzenesulfonyl chloride in the presence of triethylamine according to the procedure described in Example 1, step 1, to afford the sulfonamide 80. Ester hydrolysis and coupling with hydroxylamine were then accomplished as described in Example 28 to afford the hydroxamic acid 81.
1H NMR: (Acetone-d6) δ (ppm): 9.76 (bs, 1H), 8.83 (bs, 1H), 7.74 (d, J=8.2 Hz, 2H), 7.59-7.49 (m, 3H), 7.04 (s, 4H), 2.83-2.73 (m, 3H), 1.83 (sext, J=6.9 Hz, 1H), 1.00 (d, J=6.9 Hz, 3H), 0.93 (d, J=6.9 Hz, 3H).
HRMS: 344.1195 (M+-H2O) (calc.); 344.1200±0.0010 (found).
Example 31




Compound 82 was obtained in good yield from commercially available bromoaminopyridine through a palladium catalyzed coupling with tert-butyl acrylate. Treatment of 82 with 4-phenylbenzenesulfonyl chloride afforded a mixture of sulfonamide 84 and bis-sulfonamide 83, which was converted to 84 upon chromatographic isolation followed by basic methanolysis. Acidic cleavage of the t-butyl ester was effected by treatment of 84 with aqueous formic acid and a tert-butyl cation scavenger to afford the acrylic acid 85 in quantitative yield. Finally, coupling of 85 with o-phenylenediamine in the presence of benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP) afforded the anilide 86.
Data for 86:
1H NMR: (300.07 MHz; CD3OD): δ (ppm): 8.23 (d, J=1.9, 1H); 8.03 (bd, J=8.5; 2H); 7.96 (dd, J=1.9, 9.1; 1H); 7.76 (bd, J=8.5, 2H); 7.63 (dd, J=1.4, 8.2); 7.53 (J=15.5; 1H), 7.48-7.36 (m, 3H); 7.29 (d, J=9.1, 1H) 7.18 (dd, J=1.4, 8.0, 1H); 7.03 (dt, J=1.4, 7.8, 1H); 6.86 (d, J=1.4, 7.9, 1H) 6.76 (d, J=15.6, 1H) 6.75-6.69 (m, 1H); 4.85 (bs, 4H).
13C NMR: (75.5 MHz; CD3OD) δ (ppm): 166.4; 154.7; 146.9; 146.2; 143.1; 141.1; 140.6; 138.6; 137.9; 130.1; 129.5; 128.8; 128.5; 128.3; 126.7; 125.6; 125.0; 122.1; 120.8; 119.5; 118.6; 114.9
MS: calc for C26H22O3N4S: 470.556. found: 471.5 for [M+H] (low resolution MS).
By procedures analogous to those described in Examples 1-31 above, the following compounds were synthesized:




1H NMR: (300 MHz, CD3OD): δ=7.76-7.74 (1H, m), 7.58-7.48 (4H, m), 7.22 (2H, d, J=7.5 Hz), 7.10 (1H, t, J=5.1 Hz), 6.41 (1H, d broad, J=14.7 Hz).




1H NMR: (300 MHz, CD3OD): δ=7.79 (2H, d, J=8.1 Hz), 7.56-7.46 (5H, m), 7.17 (2H, d, J=8.1 Hz), 6.39 (1H, d, J=15.9 Hz).
Analysis: C15H13N2O4SCl X 0.1H2O, X 0.3 TFA Found: C=48.26%, H=3.58%, N=6.97%, S=7.86%. Calc.: C=48.19%, H=3.50%, N=7.20%, S=8.25%




1H NMR: (300 MHz, DMSO d6): δ=10.85 (1H, s br), 10.70 (1H, s br), 8.99 (1H, s), 8.37 (2H, d, J=9 Hz), 8.01 (2H, d, J=9 Hz), 7.44 (2H, d, J=8.7 Hz), 7.33 (1H, d, J=15.3 Hz), 7.12 (2H, d, J=8.4 Hz), 6.31 (1H, d, J=15.9 Hz).
Analysis: C15H13N3O6S X 0.4H2O, X 0.3 TFA Found: C=46.39%, H=3.49%, N=10.44%, S=7.92%. Calc.: C=46.29%, H=3.51%, N=10.38%, S=7.92%.




1H NMR: (300 MHz, DMSO d6): δ=10.70 (1H, s br), 10.33 (1H, s br), 8.99 (1H, s br), 7.44-7.26 (5H, m), 7.12 (2H, d, J=8.7 Hz), 7.06 (1H, d, J=8.4 Hz), 6.30 (1H, d, J=16.2 Hz), 3.78 (3H, s), 3.75 (3H, s)
Analysis: C17H18N2O6S X 0.2H2O Found: C=53.56%, H=5.03%, N=7.71%, S=8.01%. Calc.: C=53.45%, H=4.86%, N=7.33%, S=8.39%.




1H NMR: (CD3OD) δ (ppm): 7.78 (d, J=7.1 Hz, 1H), 7.56-7.45 (m, 3H), 7.24 (d, J=8.5 Hz, 2H), 7.12 (d, J=8.8 Hz, 2H), 7.06 (s, 1H), 2.00 (d, J=1.4 Hz, 3H).
13C NMR: (CD3OD) δ (ppm): 135.2, 132.9, 128.1, 127.7, 125.5, 124.6, 124.1, 122.3, 116.8, 115.6, 8.4.




1H NMR: (Acetone-d6) δ (ppm): 9.86 (bs, 1H), 8.86 (bs, 1H), 7.83 (bs, 1H), 7.76 (d, J=6.7 Hz, 1H), 7.62-7.48 (m, 3H), 7.10-7.03 (m, 4H), 2.87-2.79 (m, 3H), 2.56-2.39 (m, 2H), 1.05 (d, J=6.6 Hz, 3H).
HRMS: 334.0987 (calc.); 334.0991±0.0010 (found)




1H NMR: (300 MHz, DMSO d6): δ=10.94 (1H, s broad), 10.65 (1H, s broad), 8.95 (1H, s Broad), 8.73-8.71 (1H, m), 8.24-8.21 (2H, m), 8.05 (1H, m), 7.74-7.63 (3H, m), 7.33-7.23 (2H, m), 7.06-7.04 (2H, m), 6.24 (1H, d, J=15.3).
Analysis: C19H16N2O4S X 0.5H2O Found: C=60.31%, H=4.58%, N=7.43%. Calc.: C=60.46%, H=4.54%, N=7.42%




1H NMR: (300 MHz, DMSO d6): δ=10.65 (2H, s broad), 8.48 (1H, s), 8.15-8.08 (2H, m), 8.00 (1H, d, J=7.5 Hz), 7.77 (1H, d, J=9 Hz), 7.70-7.62 (2H, m), 7.39 (2H, d, J=8.4 Hz), 7.28 (1H, d, J=15.6 Hz), 7.15 (2H, d, J=8.4 Hz), 6.26 (1H, d, J=15.6 Hz).
Analysis: C19H16N2O4S X 0.2H2O, X 0.5 TFA Found: C=56.01%, H=3.94%, N=6.60%, S=7.41%. Calc.: C=55.99%, H=3.97%, N=6.53%, S=7.47%.




1H NMR: (300 MHz, DMSO d6): δ=10.91 (1H, s), 10.69 (1H, s br), 8.06-7.98 (3H, m), 7.57-7.46 (4H, m), 7.34 (1H, d, J=15.9 Hz), 7.21 (2H, d, J=8.4 Hz), 6.33 (1H, d, J=15.9 Hz).




1H NMR: (300 MHz, DMSO d6): δ=8.69-8.8 (1H, m), 8.02-8.01 (2H, m), 7.61-7.59 (1H, m), 7.52-7.43 (3H, m), 7.25 (2H, d, J=7.5 Hz), 6.37 (1H, d, J=15.9 Hz).
Analysis: C14H13N3O4S X 0.9 TFA Found: C=45.36%, H=3.51%, N=9.77%, S=7.09%. Calc.: C=44.97%, H=3.32%, N=9.96%, S=7.60%.




1H NMR: (300 MHz, DMSO d6): δ=10.91 (1H, s), 10.62 (1H, s br), 8.45 (1H, 8.1 Hz), 8.36 (1H, d, J=8.7 Hz), 8.25 (1H, d, J=6.9 Hz), 7.65-7.59 (2H, m), 7.37-7.34 (2H, m), 7.29-7.23 (2H, m), 7.06 (2H, d, J=8.7 Hz), 6.25 (1H, d, J=15.9 Hz) 2.80 (6H, s).




1H NMR: (300 MHz, DMSO d6): δ=10.82 (1H, s br), 9.95 (1H, s br), 9.12 (1H, s br), 7.70 (4H, s), 7.46 (1H, d, J=15.9 Hz), 6.79 (1H, d, J=8.7 Hz), 6.68 (1H, s), 6.56-6.51 (2H, m), 3.65 (3H, s), 3.62 (3H, s).




1H NMR: (300 MHz, DMSO d6): δ=10.63 (1H, s), 10.36 (1H, s br), 9.13-9.12 (1H, m), 8.93 (1H, s br), 8.51 (1H, d, J=8.1 Hz), 8.40 (1H, d, J=7.2 Hz), 8.28 (1H, d, J=8.4 Hz), 7.75-7.70 (2H, m), 7.30-720 (3H, m), 7.09 (2H, d, J=8.4 Hz) 6.21 (1H, d, J=15.9 Hz).
Analysis: C18H15N3O4S X 1.1H2O Found: C=55.72%, H=4.45%, N=10.64%, S=6.93%. Calc.: C=55.55%, H=4.45%, N=10.80%, S=8.24%.




1H NMR: (300 MHz, DMSO d6): δ=10.72 (1H, s br), 10.07 (1H, s), 7.53-7.51 (2H, m), 7.43-7.34 (4H, m), 7.26-7.19 (4H, m), 6.38 (1H, d, J=15.6 Hz), 4.51 (2H, s).
Analysis: C16H16N2O4S X 0.4 TFA Found: C=53.60%, H=4.46%, N=7.36%, S=7.81%. Calc.: C=53.38%, H=4.37%, N=7.41%, O=20.32%, S=8.48%, F=6.03%.




1H NMR: (300 MHz, DMSO d6): δ=10.63 (1H, s br), 10.56 (1H, s), 8.67 (1H, s), 8.29 (1H, d, J=6.9 Hz), 7.89-7.85 (2H, m), 7.75 (1H, d, J=8.4 Hz), 7.59 (1H, t, J=7.2 Hz), 7.47-7.38 (3H, m), 7.27 (1H, d, J=15.6 Hz), 7.15 (2H, d, J=8.7 Hz), 6.25 (1H, d, J=15.9 Hz).




1H NMR: (300 MHz, DMSO d6): δ=10.72 (2H, s), 8.98 (1H, s br), 7.97 (4H, s), 7.55 (2H, s), 7.45 (2H, d, J=8.7 Hz), 7.33 (1H, d, J=15.9 Hz), 7.13 (2H, d, J=8.7 Hz), 6.32 (1H, d, J=15.9 Hz).




1H NMR: (300 MHz, DMSO d6): δ=10.75 (2H, m), 7.65-7.64 (1H, m), 7.53-7.45 (4H, m), 7.35 (1H, d, J=16.2 Hz), 7.29 (1H, d, J=3.9 Hz), 7.20 (2H, d, J=8.7 Hz), 7.12 (1H, t, J=3.6 Hz), 6.34 (1H, d, J=15.6 Hz).
Analysis: C17H14N2O4S3 X 0.1H2O, X 1.0 TFA Found: C=43.83%, H=3.26%, N=5.73%, S=18.15%. Calc.: C=43.69%, H=2.93%, N=5.36%, S=18.42%.




1H NMR: (300 MHz, DMSO d6): δ=10.72 (1H, s), 8.91 (1H, d, J=1.8 Hz), 8.80-8.78 (1H, m), 8.13 (1H, d, J=7.8 Hz), 7.63-7.59 (1H, m), 7.46 (2H, d, J=8.7 Hz), 7.33 (1H, d, J=15.6 Hz), 7.14 (2H, d, J=8.7 Hz), 6.32 (1H, d, J=15.9 Hz).




1H NMR: (300 MHz, DMSO d6): δ=10.54 (1H, s), 7.73 (2H, d, J=8.4 Hz), 7.58 (2H, d, 8.4 Hz), 7.43 (2H, d, J=8.4 Hz), 7.32 (1H, d, J=15.6 Hz), 7.15 (2H, d, J=8.4 Hz), 6.30 (1H, d, J=15.9 Hz), 1.25 (9H, s).
Analysis: C19H22N2O4S X 0.3H2O, 0.6 TFA Found: C=54.17%, H=5.25%, N=6.32%, S=6.85%. Calc.: C=54.12%, H=5.22%, N=6.25%, S=7.15%.




1H NMR: (300 MHz, DMSO d6): δ=11.02 (1H, s), 10.70 (1H, s), 8.99 (1H, s br), 8.03 (1H, d, J=1.8 Hz), 7.76-7.67 (2H, m), 7.45 (2H, d, J=8.1 Hz), 7.33 (1H, d, J=15.6 Hz), 7.13 (2H, d, J=8.4 Hz), 6.31 (1H, d, J=16.2 Hz).
Analysis: C15H12N2O4SCl2 X 0.3H2O Found: C=45.96%, H=3.11%, N=7.21%, S=8.06%. Calc.: C=45.89%, H=3.23%, N=7.13%, S=8.17%.




1H NMR: (300 MHz, Acetone d6): δ=8.81 (1H, d, J=8.4 Hz), 8.34 (2H, d, J=7.2 Hz), 8.20 (1H, d, J=8.1 Hz), 8.05 (1H, d, J=7.5 Hz), 7.75-7.59 (4H, m), 7.53-7.41 (4H, m), 7.23-7.07 (4H, m), 6.89-6.86 (2H, m), 6.75 (1H, d, J=15.3 Hz).
Analysis: C25H21N3O3S X 0.4H2O, 0.6 TFA Found: C=60.68%, H=4.36%, N=8.11%, S=6.15%. Calc.: C=60.62%, H=4.35%, N=8.09%, S=6.18%.




1H NMR: (300 MHz, DMSO d6): δ=10.7 (1H, s br), 10.45 (1H, s br), 8.96 (1H, s br), 7.64 (2H, d, J=8.1 Hz), 7.38 (2H, d, J=8.4 Hz), 7.32-7.29 (3H, m), 7.09 (2H, d, J=8.4 Hz), 6.29 (1H, d, J=16.2 Hz), 2.30 (3H, s).
Analysis: C16H16N2O4S X 1.6H2O, X 1.6 TFA Found: C=42.26%, H=3.62%, N=5.45%, S=6.09%. Calc.: C=42.42%, H=3.86%, N=5.15%, S=5.9%.




1H NMR: (300 MHz, DMSO d6): δ=10.71 (1H, s), 10.67 (1H, s), 9.00 (1H, s br), 7.96 (1H, d, J=2.4 Hz), 7.85 (1H, d, J=8.4 Hz), 7.69 (1H, dd, J=8.4 Hz and 2.1 Hz), 7.47 (2H, d, J=8.4 Hz) 7.35 (1H, d, J=15.9 Hz), 7.13 (2H, d, J=8.7 Hz), 6.33 (1H, d, J=15.9 Hz).
Analysis: C15H12N2O4SCl2 X 0.3H2O, X 0.3 AcOEt Found: C=46.30%, H=3.27%, N=6.56%, S=7.57%. Calc.: C=46.43%, H=3.61%, N=6.68%, S=7.65%.




1H NMR: (300 MHz, DMSO d6): δ=1.65 (1H, s br), 10.45 (1H, s br), 8.96 (1H, s br), 7.42 (2H, d, J=8.1 Hz), 7.31 (1H, d, J=15.6 Hz), 7.22 (2H, s), 7.01 (2H, d, J=8.1 Hz), 6.30 (1H, d, J=15.9 Hz), 4.24-4.16 (2H, m), 2.93-2.84 (1H, m), 1.18-1.14 (18H, m).
Analysis: C24H32N2O4S X 1.10H2O Found: C=62.14%, H=7.17%, N=6.20%, S=6.71%. Calc.: C=62.07%, H=7.42%, N=6.03%, S=6.9%.




1H NMR: (300 MHz, DMSO d6): δ=11.18 (1H, s br), 10.69 (2H, m), 7.83-7.82 (1H, m), 7.68 (1H, m), 7.43 (2H, d, J=8.1 Hz), 7.32 (1H, d, J=15.3 Hz), 7.13 (2H, d, J=8.1 Hz), 6.31 (1H, d, J=15.9 Hz).
Analysis: C15H12N2O5SCl2 X 0.2H2O, X 0.2 TFA Found: C=43.14%, H=3.04%, N=6.54%, S=7.19%. Calc.: C=43.05%, H=2.96%, N=6.52%, S=7.46%.




1H NMR: (300 MHz, DMSO d6): δ=10.70 (1H, s), 10.65 (1H, s), 9.01 (1H, s br), 7.91 (2H, d, J=8.4 Hz), 7.56 (2H, d, J=8.4 Hz), 7.45 (2H, d, J=8.1 Hz), 7.33 (1H, d, J=15.6 Hz), 7.13 (2H, d, J=8.1 Hz), 6.31 (1H, J=15.6 Hz).
Analysis: C16H13N2O5SF3 X 0.2 TFA Found: C=46.43%, H=3.33%, N=6.22%, S=7.25%. Calc.: C=46.33%, H=3.13%, N=6.59%, S=7.54%.




1H NMR: (300 MHz, DMSO d6): δ=10.66 (1H, s br), 10.37 (1H, s br), 8.56 (1H, s br), 7.69 (2H, d, J=8.7 Hz), 7.39 (2H, d, J=8.1 Hz), 7.30 (1H, d, J=16.2 Hz), 7.10-7.03 (4H, m), 6.27 (1H, d, J=15.9 Hz), 3.77 (3H, s).
Analysis: C16H16N2O5S X 0.7H2O Found: C=53.32%, H=5.05%, N=7.98%, S=7.78%. Calc.: C=53.24%, H=4.86%, N=7.76%, S=8.88%.




1H NMR: (300 MHz, DMSO d6): δ=10.70 (1H, s), 10.66 (1H, s), 8.99 (1H, s), 8.06-7.98 (3H, m), 7.84-7.79 (1H, m), 7.45 (2H, d, J=8.4 Hz), 7.33 (1H, d, J=15.6 Hz), 7.12 (2H, d, J=8.7 Hz), 6.32 (1H, d, J=15.9 Hz).
Analysis: C16H13F3N2O4S Found: C=49.64%, H=3.30%, N=7.18%. Calc.: C=49.74%, H=3.39%, N=7.25%




1H NMR: (300 MHz, DMSO d6): δ=10.69 (1H, s, br), 10.47 (1H, s, br), 8.98 (1H, s, br), 7.62 (1H, s), 7.58-7.56 (1H, m), 7.44-7.41 (4H, m), 7.32 (1H, d, J=16.2 Hz), 7.11 (2H, d, J=8.1 Hz), 6.30 (1H, d, J=15.6 Hz), 2.34 (3H, s).
Analysis: C16H16N2O4S X 0.3 TFA Found: C=54.64%, H=4.75%, N=7.92%. Calc.: C=54.66%, H=4.59%, N=7.82%




1H NMR: (300 MHz, MeOD d4): 7.62-6.61 (m, 13H); 3.81 (broad s, 3H, OCH3), 3.80 (broad s, 3H, OCH3), 3.26 (broad s, 4H, NH).
13C NMR: (75 MHz, MeOD d4): 167.0 (C═O); 154.4; 150.5; 143.1; 141.9; 141.0; 132.5; 132.3; 129.9; 128.2; 126.7; 125.2; 122.4; 121.8; 120.8; 119.6; 118.7; 111.9; 110.9; 56.6 (2C, OCH3).
Combustion analysis: Calc: 60.91% C, 5.11% H, 9.27% N, 7.07% S
Found: 60.40% C, 5.21% H, 9.16% N, 6.47% S
HRMS: Calc: 453.1358; Found: 453.1351




1H NMR: (Acetone-d6): δ (ppm): 9.25 (bs, 1H), 8.77 (bs, 1H), 7.79 (d, J=8.5 Hz, 2H), 7.61-7.51 (m, 5H), 7.36-7.28 (m, 3H), 6.99-6.93 (m, 1H), 6.86-6.82 (m, 2H), 6.68-6.62 (m, 1H), 4.63 (bs, 2H).
HRMS: 449.1773 (calc.): 449.1767±0.0013 (found)




1H NMR: (300 MHz, MeOD d4): 8.00-6.56 (m, 13H); 3.77 (broad s, 3H, OCH3), 3.74 (broad s, 3H, OCH3), 3.33 (broad s, 2H, NH), 3.00 (broad s, 1H, NH), 2.88 (broad s, 1H, NH).
13C NMR: (75 MHz, MeOD d4): 166.2 (C═O); 150.7; 148.5; 143.2; 141.7; 140.6; 140.5; 131.9; 129.2; 128.9; 128.4; 126.7; 124.9; 119.5; 118.6; 116.4; 113.2; 108.9; 56.6 (OCH3); 56.4 (OCH3).
MS: Calc: 453.1358: Found: 453.1351




1H NMR: (CD3OD) δ (ppm): 7.68 (d, J=8.2 Hz, 2H), 7.55 (d, J=15.9 Hz, 1H), 7.47 (d, J=8.5 Hz, 2H), 7.30 (d, J=8.0 Hz, 2H), 7.19-7.12 (m, 3H), 7.03 (t, J=7.1 Hz, 1H), 6.86 (d, J=8.0 Hz, 1H), 6.75-6.69 (m, 2H), 2.37 (s, 3H).
HRMS: 407.1304 (calc.): 407.1293±0.0012 (found)




1H NMR: (300 MHz, DMSO-d6) δ 10.6 (s, OH); 9 (s, NH); 7.1-7.8 (m, 14H, CH Ar); 6.2 (d, 1H, J=15 Hz)




1H NMR: (300 MHz, MeODd4): 7.31-6.62 (m, 11H); 3.72 (broad s, 3H); 3.70 (broad s, 3H); 2.91 (t, 2H; J=7.1 Hz); 2.65 (broad t, 2H, J=7.4 Hz)
13C NMR: (75 MHz, MeODd4): 173.9; 154.0; 150.3; 143.4; 138.6; 137.4; 132.6; 130.2; 128.4; 127.4; 124.6; 123.1; 122.3; 119.3; 118.1; 111.7; 110.9; 56.5 (2C); 38.8; 32.2.
HRMS: calc: 455.1515: Found: 455.1521




1H NMR: (300 MHz, DMSO d6): 7.77 (d, 2H, J=8.8 Hz); 7.51 (d, 2H, J=8.5 Hz); 7.34 (d, 2H, J=8.8 Hz); 7.18 (d, 2H, J=8.5 Hz); 7.11 (d, 2H, 8.8 Hz); 6.94 (t, 1H, J=7.4 Hz); 6.77 (broad d, 2H, J=7.9 Hz); 6.6 (t, 1H, J=7.4 Hz), 4.95 (broad s, 1H), 3.83 (s, 3H).
13C NMR: (75 MHz, DMSO d6): 162.5; 141.5; 139.2; 138.8; 130.9; 130.2; 128.9; 128.6; 125.7; 124.7; 119.4; 116.2; 115.9; 114.5; 55.6.
HRMS: Calc: 423.1253: Found: 423.1235




1H NMR: (300 MHz, DMSO-d6) δ 7.1-7.8 (m, 14H, CH Ar); 6.8-6.9 (m, 4H, CH Ar); 6.3 (d, 1H, J=15 Hz)
Example 32




Sulfonamide 124 was prepared by condensation of 4-iodoaniline with benzenesulfonyl chloride. Compound 125 was quantitatively furnished by a Pd—Cu catalyzed coupling reaction of 124 with propargyl alcohol in basic solvent. Primary alcohol 125 was oxidized to the corresponding carboxylic acid 127 in two steps, including Dess-Martin periodinane oxidation to afford aldehyde 126, followed by treatment with sodium chlorite in buffered aqueous media in the presence of a chlorine scavenger. Acid 127 was derivatized to the hydroxamic acid 128 by treatment with hydroxylamine hydrochloride and the coupling reagent EDC in the presence of N-hydroxybenzotriazole in basic, aprotic media. Compound 129 was prepared by coupling acid 130 with o-phenylenediamine as described in Example 31 for compound 86.
Data for 128:
1H NMR: (300.07 MHz; acetone-d6) δ (ppm): 9.4 (bs, 2H); 7.93 (dd, J=1.9, 6.6; 2H); 7.82 (dd, J=1.9, 6.6; 2H); 7.68 (dd, J=1.4, 8.2; 2H); 7.48-741 (m, 5H); 7.35-7.32 (m, 2H); 2.90 (bs, 1H)
13C NMR: (75.5 MHz; acetone-d6) δ (ppm): 153.5; 147.2; 141.3; 140.3; 139.5; 134.6; 130.1; 129.5; 128.8; 128.6; 128.3; 120.8; 116.5; 87.7; 81.0.
MS: calc for C21H16O4N2S: 392.438; found: 393.4 for [M+H] (low resolution MS).
Data for 129:
1H NMR: (300.07 MHz; acetone-d6)  (ppm): 9.43 (bs, 1H); 8.02 (d, J=8.5 Hz; 2H); 7.93 (d, J=8.5 Hz; 2H); 7.90 (d, J=8.5 Hz; 2H); 7.65 (d, J=8.5 Hz; 2H); 7.47-7.34 (m, 7H); 7.21-7.17 (m, 2H); 2.80 (bs, 3H)
13C NMR: (75.5 MHz; acetone-d6) δ (ppm): 167.2; 158.6; 146.3; 141.3; 140.9; 139.8; 139.5; 134.2; 131.0; 129.9; 129.8; 129.3; 128.7; 128.6; 128.4; 128.0; 126.8; 125.1; 122.7; 122.6; 120.1
MS: calc for C27H21O3N3S: 467.552; found: 468.5 for [M+H] (low resolution MS).
Example 33




Benzylic alcohol 130 was prepared in 53% yield by addition of 2-lithiofuran to styrene oxide. After protection of the resulting hydroxyl group with tert-butyldimethylsilyl chloride, the lithiated species of compound 131 was treated with DMF to afford the formyl derivative 132. Wadsworth-Horner-Emmons olefination was effected by treatment of 132 with the sodium enolate of trimethylphosphonoacetate to afford the key intermediate 133 in 90% overall yield for the last three steps. Saponification of the methyl ester with LiOH yielded the acid 134, which in turn was converted into its hydroxamic acid form 135 by conventional activation with HOBt/EDC, followed by reaction with hydroxylamine. Fluoride-promoted cleavage of silylated ether gave alcohol 136 in 67% yield.
Data for 136:
1H NMR: (300.07 MHz; acetone-d6) δ (ppm): 9.35 (bs, 1H); 7.40-7.15 (m; 6H); 6.56 (d, J=2.9 Hz, 1H); 6.24 (d, J=15.3 Hz, 1H); 4.96 (t, J=6.2 Hz, 1 H); 3.00 (d, J=6.2 Hz, 2H)
13C NMR: (75.5 MHz; CD3OD) δ (ppm): 166.6; 156.6; 151.3; 145.2; 129.3; 128.5; 126.9; 116.2; 114.5; 111.0; 73.6; 39.1
Example 34




Unsaturated ketoacid 138 was obtained from ester 133 in 73% overall yield after three consecutive steps, including saponification (LiOH/H2O/MeOH/THF), desilylation (TBAF/THF), and oxidation of benzylic alcohol 137 using Dess-Martin periodinane. Anilide 139 was obtained by BOP-mediated condensation of compound 138 with o-phenylenediamine in 83% yield.
Regioselective hydrogenation of the acrylate moiety in 133 was accomplished by treatment with NaBH4 in the presence of NiCl2, to afford the propionate 140 in high yield. Ketoacid 142 was then obtained in 31% overall yield from 140 by an identical procedure to that followed in the synthesis of 138 from 133. With compound 142 in hand, anilide 144 was obtained as described above (BOP/o-phenylendiamine). The low yield was due to a difficult purification process. To avoid oxime formation, hydroxamic acid 143 was synthesized from 142 in 73% overall yield over two steps, including BOP-mediated coupling with N,O-bistrimethylsilylhydroxylamine, followed by cleavage of silylated groups under acidic conditions (citric acid/MeOH).
Data for 139:
1H NMR: (300.07 MHz; CDCl3) δ (ppm): 8.02-7.42 (series of multiplets, 7H); 7.34 (bs, 1H); 7.06 (m, 1H); 6.80 (d, J=7.8; 1H); 6.79 (d, J=8.1; 1H); 6.54 (d, J=3.0 Hz, 1H); 6.38 (m, 1H); 6.34 (d, J=3.0 Hz, 1H); 4.37 (s, 2H); 3.90 (bs, 2H)
13C NMR: (75.5 MHz; CDCl3) δ (ppm): 194.5; 164.4; 150.9; 150.8; 150.5; 140.5; 135.9; 133.7; 128.7; 128.5; 126.9; 125.0; 124.4; 119.4; 118.0; 117.5; 115.7; 111.3; 38.5
Data for 143:
1H NMR: (300.07 MHz; CDCl3) δ (ppm): 8.99 (bs, 1H); 8.09-7.42 (series of multiplets, 5H); 6.09 (d, J=3.0 Hz, 1H); 6.00 (d, J=3.0 Hz, 1H); 4.35 (s, 2H); 2.95 (t, J=6.60 Hz, 2H); 2.50 (t, J=3.0 Hz, 1H).
13C NMR: (75.5 MHz; CDCl3) δ (ppm): 196.2; 162.8; 153.2; 146.8; 134.9; 133.7; 128.7; 128.5; 109.3; 107.1; 38.2; 31.7; 24.2
Data for 144:
1H NMR: (300.07 MHz; CDCl3) δ (ppm): 7.99-7.42 (series of multiplets, 5H); 7.36 (bs, 1H); 7.02 (d, J=7.8, 2H); 6.73 (d, J=7.8 Hz, 2H); 6.13 (d, J=3.0 Hz, 1H); 6.04 (d, J=3.0 Hz, 1H); 4.30 (s, 2H); 3.70 (bs, 2H); 3.03 (t, J=6.9 Hz, 2H); 2.69 (t, J=6.9 Hz, 2H).
13C NMR: (75.5 MHz; CDCl3) δ (ppm): 195.4; 170.7; 153.6; 147.1; 140.9; 136.1; 133.5; 128.7; 128.5; 127.1; 125.7; 124.0; 119.2; 117.8; 109.1; 107.2; 38.4; 35.7; 24.7
Example 35
General Procedure for Synthesis of Urea Compounds




To a solution of isocyanate (1.5 mmol) in 15 mL of anhydrous dichloromethane, was added a solution of 4-anilinylmethylacrylate (1.5 mmol) in dichloromethane (10 mL). The mixture was stirred at room temperature for 15 hours. After addition of ammonium chloride solution the new mixture was extracted from dichloromethane. The organic layers were combined and washed with ammonium chloride solution, water, brine and dried over magnesium sulfate. The crude was then flashed over silica gel using CH2Cl2:MeOH (9.5:0.5) as eluent.
The following compounds were synthesized according to the general procedure:




1H NMR: (300 MHz, DMSO-d6) δ 7.5-7.7 (m, 4H, CH Ar); 7.5 (d, 2H, J=6.6 Hz); 7.3 (d, 2H, J=6.6 Hz); 6.3 (d, 1H, J=15 Hz)




1H NMR: (300 MHz, DMSO-d6) δ 7.5-8.2 (m, 7H, CH Ar); 7.5 (d, 2H, J=6.6 Hz); 7.3 (d, 2H, J=6.6 Hz); 6.3 (d, 1H, J=15 Hz)




1H NMR: (300 MHz, DMSO-d6) δ 7.5-7.7 (m, 3H, CH Ar); 7.5 (d, 2H, J=6.6 Hz); 7.3 (d, 2H, J=6.6 Hz); 6.3 (d, 1H, J=15 Hz)
Example 36
The following additional compounds were prepared by procedures analogous to those described in the foregoing Examples:




1H NMR (300.072 MHz, (CD3)2CO): δ 1.99 (m, 2H), 2.79 (t, 2H, J=7.2 Hz), 3.21 (dd, 2H, J=6.8, 7.8 Hz), 7.27 (d, 2H, J=8.1 Hz), 7.65 (t, 2H, J=7.8 Hz), 7.72-7.77 (m, 3H), 7.90 (d, 2H, J=7.2 Hz), 10.77 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 25.2 (t), 34.3 (t), 55.6 (t), 128.0 (d), 2×128.8 (d), 129.4 (d), 2×130.2 (d), 131.1 (s), 134.5 (d), 140.7 (s), 145.5 (s), 165.8 (s).




1H NMR (300.072 MHz, (CD3)2CO): δ 1.66-1.88 (m, 4H), 2.71 (t, 2H, J=6.3 Hz), 4.34 (d, 1H, J=303 Hz), 4.87 (m, 1H), 7.27 (d, 2H, J=7.8 Hz), 7.44-7.48 (m, 2H), 7.52 (dd, 1H, J=1.5, 9.4 Hz), 7.73 (d, 2H, J=7.8 Hz), 7.83 (s, 1H), 7.83-7.88 (m, 3H), 8.16 (broad s, 1H), 10.67 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 28.3 (t), 36.2 (t), 39.8 (t), 74.0 (d), 125.0 (d), 125.3 (d), 126.2 (d), 126.7 (d), 2×127.8 (d), 128.4 (d), 128.5 (d), 128.6 (d), 2×129.3 (d), 130.6 (s), 133.7 (s), 134.3 (s), 144.7 (s), 147.4 (s), 165.9 (s).




1H NMR: (300 MHz, DMSO-d6) δ 11.2 (s, OH); 9 (s, NH); 7.6-7.8 (m, 4H, CH Ar); 7-7.4 (m, 5H, CH Ar); 2.8 (m, 4H, CH2).




1H NMR: (300 MHz, DMSO-d6) δ 11.2 (s, 1H); 9.0 (s, 1H); 7.7 (m, 6H); 7.34 (m, 5H).




1H NMR: (300 MHz, DMSO-d6) δ 11.2 (s, OH); 9 (s, NH); 7.6-7.8 (m, 4H, CH Ar); 7-6.8 (m, 4H, CH Ar); 2.9 (s, 6H, 2CH3); 2.8 (m, 4H, CH2).




1H NMR (300.072 MHz, (CD3)2CO): δ 1.38 (quintuplet, 2H, J=7.5 Hz), 1.60-1.72 (m, 4H), 2.60 (t, 2H, J=7.8 Hz), 2.67 (t, 2H, J=7.5 Hz), 7.15-7.31 (m, 7H), 7.75 (d, 2H, J=8.1 Hz), 8.11 (broad s, 1H), 10.68 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 31.8 (t), 32.1 (t), 36.2 (t), 36.4 (t), 126.4 (d), 127.8 (d), 2×129.0 (d), 2×129.2 (d), 2×129.3 (d), 143.3 (s).




1H NMR (300.072 MHz, (CD3)2CO): δ 1.63 (m, 4H, J=4.5 Hz), 2.37 (t, 2H, J=7.8 Hz), 2.57-2.66 (m, 4H), 2.86 (t, 2H, J=7.5 Hz), 7.10-7.28 (m, 9H), 8.01 (broad s, 1H), 9.98 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 31.0 (t), 2×31.9 (t), 35.1 (t), 35.8 (t), 36.2 (t), 126.4 (d), 2×129.0 (d), 2×129.1 (d), 2×129.1 (d), 129.2 (d), 138.8 (s), 141.2 (s), 143.4 (s), 164.1 (s).




1H NMR (300.072 MHz, (CD3)2CO): δ 1.83-1.98 (m, 4H), 2.08-2.14 (m, 2H), 2.56-2.67 (m, 6H), 7.12-7.30 (m, 9H), 9.98 (broad s, 1H).




1H NMR (300.072 MHz, (CD3)2CO): δ 1.60-1.68 (m, 4H), 1.87 (quintuplet, 2H, J=7.5 Hz), 2.03-2.14 (m, 2H), 2.55-2.67 (m, 6H), 7.09-7.28 (m, 9H).




1H NMR (300.072 MHz, (CD3)2CO): δ 2.37 (t, 2H, J=7.2 Hz), 2.78-2.89 (m, 6H), 7.13-7.29 (m, 9H), 7.84 (broad s, 1H), 9.90 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 31.6 (t), 35.1 (t), 38.2 (t), 38.6 (t), 2×126.6 (d), 2×129.1 (d), 2×129.2 (d), 2×129.3 (d), 139.4 (s), 140.4 (s), 142.8 (s), 170.1 (s).




1H NMR (300.072 MHz, (CD3)2CO): δ 1.96 (quintuplet, 2H, J=6.0 Hz), 2.69 (t, 2H, J=8.0 Hz), 3.19 (dd, 2H, J=6.0, 9.0 Hz), 3.38 (s, 2H), 7.09 (d, 2H, J=7.5 Hz), 7.21 (d, 2H, J=7.5 Hz), 7.66 (t, 2H, J=8.1 Hz), 7.747 (t, 1H, J=6.9 Hz), 7.90 (d, 2H, J=6.6 Hz), 10.08 (broad s, 1H).
13C NMR (75.46 MHz, (CD3)2CO): δ 25.5 (t), 34.1 (t), 39.9 (t), 55.7 (t), 2×128.8 (d), 130.0 (d), 2×130.2 (d), 134.4 (s), 139.9 (s), 140.7 (s), 168.5 (s).




1H NMR: (300 MHz, DMSO d6): δ 7.77 (broad s, 4H); 7.57 (d, 1H, J=15.7 Hz); 7.35 (d, 1H, J=6.9 Hz); 7.03-6.94 (m, 6H); 6.76 (d, 1H, J=7.1 Hz); 6.59 (d, 1H, J=6.9 Hz); 4.98 (broad s, 2H); 2.19 (s, 3H).
13C NMR: (75 MHz, DMSO d6): δ 162.9; 141.6; 139.8; 139.0; 137.6; 134.8; 133.6; 129.6; 128.1; 127.3; 125.9; 125.4; 124.7; 123.2; 120.7; 116.2; 115.9; 20.3.




1H NMR: (300 MHz, DMSO d6): δ 7.91-7.81 (m, 4H); 7.63-7.58 (m, 5H); 7.48-7.43 (m, 2H); 7.39-7.33 (m, 2H); 7.24 (d, 2H, J=8.5 Hz); 6.97 (dd, 2H, J=9.9, 7.1 Hz); 6.79 (d, 1H, J=7.7 Hz)6.61 (dd, 1H, J=7.7, 7.1 Hz); 5.01 (broad s, 2H).
13C NMR: (75 MHz, DMSO d6): δ 162.9; 141.9; 141.6; 139.8; 139.2; 137.6; 136.9; 135.8; 128.9; 128.3; 127.4; 127.3; 127.2; 126.3; 126.0; 125.5; 124.8; 123.2; 120.4; 116.2; 115.9.




1H NMR: (300 MHz, MeODd4): δ 7.74-7.54 (m, 5H); 7.07-6.96 (m, 4H); 6.55 (d, 1H, J=15.7); 2.25 (s, 3H).
13C NMR: (75 MHz, MeODd4): δ 163.5; 141.6; 140.4; 139.5; 136.1; 135.9; 130.6; 129.0; 128.8; 123.1; 121.7; 20.8




1H NMR: (300 MHz, MeODd4): δ 7.83-7.19 (m, 14H); 6.56 (d, 1H, J=15.7 Hz).
13C NMR: (75 MHz, MeODd4): δ 165.4; 141.6; 141.4; 140.5; 139.5; 139.0; 137.9; 129.8; 129.2; 128.7; 128.6; 128.2; 127.6; 122.7; 121.7.
Example 37




To a solution of carboxylic acid 163 (131 mg, 0.36 mmol), prepared according to procedures described above, in 6 mL of dry DMF was added Et3N (190 μl, 1.37 mmol), followed by the addition of solid BOP (259 mg; 0.59 mmol). The reaction mixture was stirred for 10 min. at room temperature and then solid 5-amino-1,3,4-thiadiazole-2-thiol (58 mg, 0.43 mmol) was added. After being stirred for 12 h, the mixture was diluted with methanol and concentrated under vacuum. Upon dilution with CH2Cl2/MeOH, crystallization of 164 (150 mg, 87%) from the crude oil took place.
1H NMR: (300 MHz, DMSO d6): δ 7.85 (broad s, 5H); 7.04-6.58 (m, 4H); 3.69 (s, 3H); 3.67 (s, 3H); 3.38 (broad s, 3H).
13C NMR: (75 MHz, DMSO d6): 163.3; 161.7; 158.7; 148.7; 146.2; 142.0; 140.7; 137.9; 130.1; 128.7; 127.5; 121.4; 113.7; 112.0; 106.6; 55.5; 55.4.
Following this general procedure, the following thiadiazole derivatives were prepared from the corresponding carboxylic acids:




1H NMR: (300 MHz, DMSO-d6); δ (ppm): 7.89-7.72 (series of multiplets, 7H); 7.50-7.05 (series of multiplets, 6H); 3.32 (broad singlet, 3H)
13C NMR: (75 MHz, DMSO-d6); d (ppm): 162.6; 162.3; 144.5; 138.3; 138.3; 138.2; 132.5; 130.1; 129.7; 129.1; 128.6; 127.6; 127.3; 127.1; 120.9; 118.7; 116.8.
MS: calc. for M+H, 493.6. obs. for M+H, 496.3




1H NMR: (300 MHz, DMSO d6): 7.87-7.72 (m, 5 H), 7.57-7.53 (m, 4 H), 7.39 (dd, 2H, J=6.9, 7.7 Hz), 7.30 (d, 1 H, J=7.1 Hz), 7.17 (d, 2 H, J=8.5 Hz), 6.85 (d, 1 H, J=15.9 Hz).
MS: cal: 495.61; found: 496.6
Following an analogous procedure, but substituting 2-amino-5-trifluoro-methyl-1,3,4-thiadiazole for 5-amino-1,3,4,-thiadiazol-2-thiol, the following compound was prepared:




1H NMR: (300 MHz, DMSO d6):  7.96-7.81 (m, 5H); 7.71-7.48 (m, 4H); 7.38 (dd, 2H, J=7.1, 7.41 Hz); 7.28 (d, 1H, J=7.1 Hz); 7.19 (d, 2H, J=8.5 Hz); 6.98 (d, 1H, J=15.7 Hz).
13C NMR: (75 MHz, DMSO d6): 192.3; 163.6; 161.6; 142.4; 140.9; 139.2; 138.0; 136.8; 135.9; 129.0; 128.8; 127.4; 127.2; 126.2; 121.2; 120.4.
MS: cal: 530.55 found: 531.5
Example 38




Coupling of 24 (from Example 15) with o-phenylenediamine in the presence of benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP) afforded the anilide 168.
By an analogous procedure, the corresponding para-substituted compound is prepared from 32 (from Example 16).
Example 39




Step 1: N-Methyl-4-iodophenylbenzenesulfonamide (169)

To compound 28 (from Example 18) (500 mg, 1.39 mmol) in DMF (10 mL) were added at room temperature K2CO3 (962 mg, 6.96 mmol), followed by methyl iodide (395 mg, 2.78 mmol). The resulting reaction mixture was stirred at room temperature for 16 hours. The solvent is then removed and water was added. The resulting mixture was extracted with ethyl acetate, and the combined organic phases were dried and concentrated. Purification by flash chromatography using hexane:ethyl acetate (8:2) afforded 510 mg (98%) of the title compound as a white solid.
Compound 169 was converted to the hydroxamic acid 170 according to the procedures described in Example 18 for the preparation of compound 36.
Data for 170:
1H NMR: (300 MHz, DMSO d6): δ=10.76 (1H, s), 9.04 (1H, s), 7.73-7.68 (1H, m), 7.61-7.51 (6H, m), 7.43 (1H, d, J=15.9 Hz), 7.15 (2H, d, J=8.7 Hz), 6.43 (1H, d, J=16.2 Hz), 3.15 (3H, s).
Analysis: C16H16N2O4S X 0.5H2O Found: C=56.36%, H=5.09%, N=8.69%, S=8.33%. Calc.: C=56.29%, H=5.02%, N=8.21%, S=9.39%.
Example 40
N-hydroxy-2-(4-(4-phenylbutyl)phenyl)acetamide (174)
Step 1: Methyl 2-(4-iodophenyl)acetate




A 4M solution of HCl in dioxane (50 mL) was added to 2-(4-iodophenyl)acetic acid (10 g, 38.2 mmol) in MeOH (100 mL) and the reaction stirred overnight. The solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography eluting with 0-30% EtOAc in hexanes to afford methyl 2-(4-iodophenyl)acetate in 10.42 g (99%). LRMS: 276.0 (calc) 277.1 (found)(MH+)+.
Step 2: Methyl 2-(4-(4-phenylbut-1-ynyl)phenyl)acetate




CuI (0.06 equiv, 207 mg, 1.1 mmol) was added to a solution of Pd(Ph3P)4 (0.03 equiv, 628 mg, 0.54 mmol) and aromatic iodide (1 equiv, 5 g, 18 mmol) in Et2NH:DME (30 mL: 30 mL) and the reaction stirred for 20 min. 4-phenyl-1-butyne (3 equiv, 7.1 g, 54 mmol) was then added dropwise and the reaction stirred for 3 h. The reaction was concentrated under reduced pressure and then the residue partitioned between EtOAc (50 mL) and H2O (50 mL). The organic phase was separated, dried over Na2SO4 filtered and concentrated. The compound was purified by silica gel flash column chromatography: 20%-100% EtOAc in hexanes to afford methyl 2-(4-(4-phenylbut-1-ynyl)phenyl)acetate in 4.95 g (98%). LRMS: 278.3 (calc) 279.2 (found)(MH)+.
Step 3: Methyl 2-(4-(4-phenylbutyl)phenyl)acetate




10% Pd/C (20% w/w, 1 g) was added to a solution of the acetylene (4.9 g, 18 mmol) in MeOH (30 mL). The reaction was then purged with H2 and stirred overnight. The solvent was evaporated and the residue was purified by a silica plug eluting with 30% EtOAc in hexanes to afford methyl 2-(4-(4-phenylbutyl)phenyl)acetate in 4.99 g (99%). LRMS: 282.3 (calc) 283.1 (found)(MH)+.
Step 4: N-hydroxy-2-(4-(4-phenylbutyl)phenyl)acetamide (174)




NaOH (6 equiv, 4.2 g, 106 mmol) was added to a solution of the methyl ester (1 equiv, 4.9 g, 18 mmol) and aq. NH2OH (50 equiv, 58 g, 884 mmol) in MeOH (100 mL) and THF (100 mL) at 23° C. After stirring the reaction overnight, the reaction was adjusted to pH=7. The solvent was evaporated and the residue was purified by trituration with hexanes and water to afford N-hydroxy-2-(4-(4-phenylbutyl)phenyl)acetamide 174 in 4.66 g (93%).
(dDMSO) δ(ppm) 1H, 10.59(s, 1H), 8.77(s, 1H), 7.25-7.06(m, 9H), 3.19(s, 2H), 2.58-2.53(m, 4H), 1.54-1.52(m, 4H). LRMS: 283.1 (calc) 282.0 (MH)−.
Example 41
N-hydroxy-2-(4-(4-(2,4,5-trifluorophenyl)butyl)phenyl)acetamide (179)
Step 1: Methyl 2-(4-(3-hydroxyprop-1-ynyl)phenyl)acetate




Following the procedure of Step 2 of Example 40 above afforded methyl 2-(4-(3-hydroxyprop-1-ynyl)phenyl)acetate in 1.17 g (79%) as a thick yellow oil. (MeOD-d4) δ(ppm) 1H, 7.36 (d, J=8.4 Hz, 2H), 7.24 (d, J=8.0 Hz, 2H), 4.38 (s, 2H), 3.67 (s, 3H), 3.65 (s, 2H).
Step 2: Methyl 2-(4-(3-hydroxypropyl)phenyl)acetate




Following the procedure of Step 3 of Example 40 above afforded methyl 2-(4-(3-hydroxypropyl)phenyl)acetate in 1.18 g (99%) a clear translucent oil. (MeOD-d4) δ(ppm) 1H, 7.15 (d, J=1.6 Hz, 4H), 3.66 (s, 3H), 3.59 (s, 2H), 3.55 (t, J=6.4 Hz, 2H), 2.65 (t, J=7.6 Hz, 2H), 1.82 (m, 2H).
Step 3: Methyl 2-(4-(3-oxopropyl)phenyl)acetate




TEMPO (0.02 equiv, 6 mg, 0.038 mmol) was added to a solution of methyl 2-(4-(3-hydroxypropyl)phenyl)acetate in CH2Cl2 (5 mL) and cooled to 0° C. KBr (2.2 equiv, 1.6 mL, 2.7M) and KHCO3 (5.5 equiv, 6.6 mL, 1.6M) solutions were then added followed by the dropwise addition of 10% aq. NaOCl (1.34 equiv, 1.9 g, 2.6 mmol). Once the addition was complete, the reaction was stirred for an additional 10 min. at 0° C. The reaction was quenched with sat. aq. sodium thiosulfate solution (3 mL) and then partitioned between H2O (10 mL) and CH2Cl2 (10 mL). The organic phase was separated and the remaining aqueous phase was extracted with EtOAc (2×2 mL). The organic layers were combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The resulting aldehyde was carried forward to the subsequent reaction without further purification. LRMS: 206.1 (calc) 207.2 (found)(MH)+.
Step 4: Methyl 2-(4-(but-3-ynyl)phenyl)acetate




Dimethyl-2-oxopropylphosphonate (1.2 equiv, 1.5 g, 9.1 mmol) was added to a suspension of K2CO3 (3 equiv, 3.1 g, 23 mmol) and p-TsN3 (1.2 equiv, 1.8 g, 9.1 mmol) in MeCN (144 mL). The mixture was then stirred for 2 h. A solution of the methyl 2-(4-(3-oxopropyl)phenyl)acetate (1 equiv, 1.56 g, 7.6 mmol) in MeOH was then added in one portion and the reaction was stirred overnight. The solvent was evaporated under reduced pressure. The residue was partitioned between Et2O (100 mL) and water (100 mL). The aqueous phase was separated and extracted with Et2O (25 mL) twice. The organic phases were combined, dried over Na2SO4, filtered and concentrated. The residue was purified by silica gel flash column eluting with 0-30% EtOAc in hexanes to afford methyl 2-(4-(but-3-ynyl)phenyl)acetate in 980 mg (64%). LRMS: 202.5 (calc) 225.1 (found)(MNa)+.
Step 5: Methyl 2-(4-(4-(2,4,5-trifluorophenyl)but-3-ynyl)phenyl)acetate




Following the procedure of Step 2 of Example 40 above afforded methyl 2-(4-(4-(2,4,5-trifluorophenyl)but-3-ynyl)phenyl)acetate in 95 mg (39%) as a yellow oil. LRMS: 332.3 (calc) 355.3 (found)(MNa)+.
Step 6: Methyl 2-(4-(4-(2,4,5-trifluorophenyl)butyl)phenyl)acetate




Following the procedure of Step 3 of Example 40 above afforded methyl 2-(4-(4-(2,4,5-trifluorophenyl)butyl)phenyl)acetate in 91 mg (95%) as a clear translucent oil.
LRMS: 336.3 (calc) 359.2 (found)(MNa)+.
Step 7: N-hydroxy-2-(4-(4-(2,4,5-trifluorophenyl)butyl)phenyl)acetamide (179)




Following the procedure of Step 4 of Example 40 above afforded N-hydroxy-2-(4-(4-(2,4,5-trifluorophenyl)butyl)phenyl)acetamide 179 in 52 mg (57%) as a white powder. (MeOD-d4) δ(ppm) 1H, 7.15 (m, 6H), 3.35 (s, 2H), 2.61 (m, 4H), 1.60 (m, 4H). LRMS: 337.3 (calc) 338.3 (found)(MH)+.
Example 42
2-(4-(4-(benzo[c][1,2,5]oxadiazol-5-yl)but-3-ynyl)phenyl)-N-hydroxyacetamide (180)




Following the procedure of Step 4 of Example 40 above afforded 2-(4-(4-(benzo[c][1,2,5]oxadiazol-5-yl)but-3-ynyl)phenyl)-N-hydroxyacetamide 180 in 8 mg (57%) as a yellowish orange powder. (MeOD-d4) δ(ppm) 1H, 10.62 (s, 1H), 8.79 (s, 1H), 8.07 (s, 1H), 8.03 (d, J=9.2 Hz, 1H), 7.40 (d, J=9.6 Hz, 1H), 7.24 (d, J=8.4 Hz, 2H), 7.18 (d, J=8.0 hz, 2H), 3.23 (s, 3H), 2.83 (m, 2H), 2.77 (m, 2H) LRMS: 321.1 (calc) 320.3 (found)(MH)−.
Example 43
N-Hydroxy-2-(3-(4-phenylbutyl)phenyl)acetamide (181)
Step 1: Methyl 2-(3-(4-hydroxybut-1-ynyl)phenyl)acetate




Following the procedure of Step 2 of Example 40 above afforded methyl 2-(3-(4-hydroxybut-1-ynyl)phenyl)acetate in 227 mg (34%) as a yellow oil. LRMS: 218.2 (calc) 219.1 (found)(MH)+.
Step 2: Methyl 2-(3-(4-hydroxybutyl)phenyl)acetate




Following the procedure of Step 3 of Example 40 above afforded methyl 2-(3-(4-hydroxybutyl)phenyl)acetate in 181 mg (78%) as a clear translucent oil. LRMS: 222.3 (calc) 223.1 (found)(MH)+.
Step 3: Methyl 2-(3-(4-oxobutyl)phenyl)acetate




Following the procedure of Step 3 of Example 41 above afforded methyl 2-(3-(4-oxobutyl)phenyl)acetate in 178 mg (99%) as a clear translucent oil. LRMS: 220.3 (calc) 221.4 (found)(MH)+.
Step 4: Methyl 2-(3-(4-hydroxy-4-phenylbutyl)phenyl)acetate




A 1.0 M solution of PhMgBr (1 equiv, 0.45 mmol) was added dropwise to a solution of methyl 2-(3-(4-oxobutyl)phenyl)acetate (1 equiv, 100 mg, 0.45 mmol) in THF (2 mL) at 0° C. The reaction was then allowed to warm to 23° C. over 1 h. The reaction was quenched by the addition on sat. aq. NH4Cl (10 mL). The aqueous phase was separated and extracted with EtOAc (2×5 mL). The organic layers were then combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography eluting with 0-50% EtOAc in hexanes to afford methyl 2-(3-(4-hydroxy-4-phenylbutyl)phenyl)acetate in 78 mg (58%) as a clear translucent oil. LRMS: 298.4 (calc) 321.2 (found)(MH)+.
Step 5: Methyl 2-(3-(4-phenylbutyl)phenyl)acetate




Following the procedure of Step 3 of Example 40 above afforded methyl 2-(3-(4-phenylbutyl)phenyl)acetate in 15 mg (20%) as a clear translucent oil. LRMS: 282.4 (calc) 283.2 (found)(MH)+.
Step 6: N-Hydroxy-2-(3-(4-phenylbutyl)phenyl)acetamide (181)




Following the procedure of Step 4 of Example 40 above afforded N-Hydroxy-2-(3-(4-phenylbutyl)phenyl)acetamide (181) in 5 mg (33%) as a white powder. (CD3OD) δ (ppm) 1H, 7.23 (m, 9H), 3.36 (s, 2H), 2.61 (m, 4H), 1.63 (m, 4H) LRMS(ESI): (calc.) 283.1 (found) 282.2 (MH)−
Example 44
The following additional compounds were prepared by procedures analogous to those described in the Examples 40-43:
a) N-hydroxy-2-(4-(4-(4-(trifluoromethyl)phenyl)butyl)phenyl)acetamide (182)




(CD3OD) δ(ppm) 1H, 7.53 (d, J=8.4 Hz, 2H), 7.33 (d, J=8.0 Hz, 2H), 7.18 (d, J=8.0 Hz, 2H), 7.10 (d, J=8.0 Hz, 2H), (s, 2H), 2.70 (t, J=7.2 Hz, 2H), 2.61 (t, J=7.2 Hz, 2H), 1.63 (m, 4H). LRMS(ESI): (calc.) 351.14 (found) 350.24(MH)−.
b) 2-(4-(4-(1H-indol-5-yl)butyl)phenyl)-N-hydroxyacetamide (183)




(CD3OD) d(ppm) 1H, 7.29 (m, 1H), 7.24 (d, J=8.8 Hz, 1H), 7.18-7.16 (m, 3H), 7.11-7.09 (m, 2H), 6.90 (dd, J=8.4 Hz, 1.6 Hz, 1H), 6.34 (d, J=4 Hz, 1H), 3.35 (s, 2H), 2.68 (t, J=7.2 Hz, 2H), 2.61 (t, J=7.2 Hz, 2H), 1.64 (m, 4H) LRMS(ESI): (calc.) 322.17 (found) 323.421 (MH)+.
c) N-hydroxy-2-(4-(4-(3-(trifluoromethyl)phenyl)butyl)phenyl)acetamide (184)




(dDMSO) δ(ppm) 1H: 10.60 (s, 1H), 8.77 (s, 1H), 7.50 (m, 4H), 7.12 (d, J=8.0 Hz, 2H), 7.07 (d, J=8.0 Hz, 2H), 3.19 (s, 2H), 2.68 (t, J=7.2 Hz, 2H), 2.54 (t, J=7.2 Hz, 2H), 1.55 (m, 4H). LRMS(ESI): (calc.) 351.1 (found) 350.3 (MH)−.
d) N-hydroxy-2-(4-(4-(2-(trifluoromethyl)phenyl)butyl)phenyl)acetamide




(dDMSO) d(ppm) 1H: 10.60 (s, 1H), 8.77 (s, 1H), 7.63 (d, J=8.0 Hz, 1H), 7.57 (t, J=7.2 Hz, 1H), 7.43 (d, J=7.6 Hz, 1H), 7.37 (t, J=8.0 Hz, 1H), 7.13 (d, J=8.0 Hz, 2H), 7.09 d, J=8.0 Hz, 2H), 3.20 (s, 2H), 2.73 (t, J=7.6 Hz, 2H), 1.58 (m, 4H). LRMS(ESI): (calc.) 351.1 (found) 350.3 (MH)−.
e) N-hydroxy-2-(4-(4-(imidazo[1,2-a]pyridin-6-yl)butyl)phenyl)acetamide (186)




(CD3OD) d(ppm) 1H, 8.19 (s, 1H), 7.73 (s, 1H), 7.49 (s, 1H), 7.43 (d, J=9.2 Hz, 1H), 7.15 (m, 5H), 3.34 (s, 2H), 2.63 (m, 4H), 1.66 (m, 4H). LRMS(ESI): (calc.) 323.1 (found) 324.3 (MH)+
f) 2-(4-(4-(benzo[d][1,3]dioxol-5-yl)butyl)phenyl)-N-hydroxyacetamide (187)




(dDMSO) d(ppm) 1H: 10.60 (s, 1H), 8.78 (s, 1H), 7.12 (d, J=8.0 Hz, 2H), 7.07 (d, J=8.0 Hz, 2H), 6.75 (m, 2H), 6.60 (d, J=8.0 Hz, 1H), 5.92 (s, 2H), 3.19 (s, 2H), 2.52 (m, 4H), 1.50 (m, 4H). LRMS(ESI): (calc.) 327.1 (found) 326.4 (MH)−.
g) 2-(4-(4-(benzo[d][1,3]dioxol-5-yl)but-3-ynyl)phenyl)-N-hydroxyacetamide (188)




(dDMSO) d(ppm) 1H: 10.61 (s, 1H), 8.78 (s, 1H), 7.20 (d, J=8.4 Hz, 2H), 7.16 (d, J=8.4 Hz, 2H), 6.85 (m, 3H), 6.01 (s, 2H), 3.22 (s, 2H), 2.77 (t, J=7.6 Hz, 2H), 2.61 (t, J=6.8 Hz, 2H). LRMS(ESI): (calc.) 323.1 (found) 322.2 (MH)−.
i) N-hydroxy-2-(4-(2-phenoxyethoxy)phenyl)acetamide (190)




(DMSO) d(ppm) 1H, 10.58 (bs, 1H), 8.77 (bs, 1H), 7.28 (t, J=7.6 Hz<2H), 7.15 (d, J=8.8 Hz, 2H), 6.93 (m, 5H), 4.26 (s, 4H), 3.18 (s, 2H). LRMS(ESI): (calc.) 287.3 (found) 310.0 (MH)+.
j) N-hydroxy-2-(4-(3-phenoxypropyl)phenyl)acetamide (191)




(CD3OD) d(ppm) 1H, 7.21 (m, 6H), 6.88 (m, 6H), 3.92 (t, J=8 Hz, 2H), 3.35 (s, 2H), 2.77 (t, J=7.2 Hz, 2H), 2.04 (m, 2H). LRMS(ESI): (calc.) 285.3 (found) 286.2 (MH)+.
k) 2-(4-butylphenyl)-N-hydroxyacetamide (192)




(CD3OD) d(ppm) 1H, 7.18 (d, J=8 Hz, 2H), 7.11 (d, J=8 Hz, 2H), 3.35 (s, 2H), 2.57 (T, J=7.6 Hz, 2H), 1.56 (m, 2H), 1.33 (m, 2H), 0.92 (t, J=7.2 Hz, 2H). LRMS(ESI): (calc.) 207.2 (found) 208.1 (ES+;Na+).
1) N-hydroxy-2-(4-(5-phenylpentyl)phenyl)acetamide (193)




(CD3OD) d(ppm) 1H, 7.22-7.08(m, 9H), 3.34 (s, 2H), 2.56 (m, 4H), 1.61 (m, 4H), 1.34 (m, 2H). LRMS(ESI): (calc.) 297.4 (found) 298.3 (MH)+.
m) N-hydroxy-2-(4-(4-hydroxy-4-(pyridin-4-yl)butyl)phenyl)acetamide (194)




(CD3OD) d(ppm) 1H, 8.44 (d, J=6.0 Hz, 2H), 7.36 (d, J=6.4 Hz, 2H), 7.18 (d, J=8.4 Hz, 2H), 7.09 (d, J=8.0 Hz, 2H), 4.65 (m, 1H), 3.34 s, 2H), 2.60 (m, 2H), 1.69 (m, 4H). LRMS(ESI): (calc.) 300.3 (found) 301.3 (MH)+.
n) N-hydroxy-2-(4-(4-hydroxy-4-(pyridin-3-yl)butyl)phenyl)acetamide (195)




(CD3OD) d(ppm) 1H, 8.46 (s, 1H), 8.41 (d, J=4.8 Hz, 1H), 7.78 (d, J=8.0 Hz, 1H), 7.39 (t, J=5.6 Hz, 1H), 7.18 (d, J=8.0 Hz, 2H), 7.09 (d, J=8.0 Hz, 2H), 4.69 (m, 1H), 3.34 (s, 2H), 2.61 ((t, J=6.4 Hz, 2H), 1.79-1.58 (m, 4H). LRMS(ESI): (calc.) 300.5 (found) 301.4 (MH)+.
o) N-hydroxy-2-(4-(4-hydroxy-4-(pyridin-2-yl)butyl)phenyl)acetamide (196)




(CD3OD) d(ppm) 1H, 8.42 (m, 1H), 7.81 (m, 1H), 7.51 (d, J=7.2 Hz, 1H), 7.26 (d, J=4.8 Hz, 1H), 7.16 (m, 1H), 7.08 (m, 2H), 4.69 (m, 1H), 3.34 (s, 2H), 2.59 (m, 2H), 1.76-1.69 (m, 4H). LRMS(ESI): (calc.) 300.3 (found) 301.4 (MH)+.
p) N-hydroxy-2-(4-(4-(pyridin-4-yl)butyl)phenyl)acetamide (197)




(CD3OD) d(ppm) 1H, 8.37 (d, J=6.0 Hz, 2H), 7.24 (d, J=5.6 Hz, 2H), 7.18 (d, J=8.0 Hz, 2H), 7.10 (d, J=8.0 Hz, 2H), 3.35 (s, 2H), 2.67(t, J=6.4 Hz, 2H), 2.62 (t, J=7.2 Hz, 2H), 1.65 (m, 4H). LRMS(ESI): (calc.) 284.1 (found) 285.3 (MH)+.
q) N-hydroxy-2-(4-(4-(pyridin-3-yl)butyl)phenyl)acetamide (198)




(CD3OD) d(ppm) 1H, 8.24 (m, 2H), 7.65 (d, J=8.0 Hz, 1H), 7.33 (m, 1H), 7.18 (d, J=7.6 Hz, 2H), 7.10 (d, J=7.6 Hz, 2H), 3.35 (s, 2H), 2.64 (m, 4H), 1.64 (m, 4H). LRMS(ESI): (calc.) 284.1 (found) 285.3 (MH)+.
r) N-hydroxy-2-(4-(4-(pyridin-2-yl)butyl)phenyl)acetamide (199)




(CD3OD) d(ppm) 1H, 8.39 (d, J=6.0 Hz), 7.75 (t, J=8.0 Hz, 1H), 7.23 (m, 4H), 7.10 (d, J=8.0 Hz, 2H), 3.34 (s, 2H), 2.78 (t, J=7.6 Hz, 2H), 2.61 (t, J=7.6 Hz, 2H), 1.67 (m, 4H). LRMS(ESI): (calc.) 284.1 (found) 285.4 (MH)+.
s) N-hydroxy-2-(4-(3-phenylpropyl)phenyl)acetamide (200)




(CD3OD) d (ppm): 7.24-7.11 (m, 9H), 3.35 (s, 2H), 2.60 (t, 4H, J=7.6 Hz), 1.89 (m, 2H). LRMS: 269.1 (calc) 270.1 (found).
t) N-hydroxy-4-(5-phenylpentyl)benzamide (201)




(CD3OD) d(ppm) 1H, 7.64 (d, J=7.6 Hz, 2H), 7.22 (m, 4H), 7.12 (m, 3H), 2.63 (t, J=7.6 Hz, 2H), 2.57 (t, J=7.2 Hz, 2H), 1.63 (m, 4H), 1.35 (m, 2H). LRMS(ESI): (calc.) 283.4 (found) 284.3 (MH)+.
Example 45
N-(1-aminocyclopropanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174a)
Step 1: tert-butyl-1-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)cyclopropylcarbamate




N-hydroxy-2-(4-(4-phenylbutyl)phenyl)acetamide 174 (1 equiv, 156 mg, 0.55 mmol) was dissolved in DMF (3 mL). 1-(tert-butoxycarbonylamino)cyclopropanecarboxylic acid (1.5 equiv, 166 mg, 0.83 mmol) was then added followed by the sequential addition of HOBt (1 equiv, 74 mg, 0.55 mmol) and EDC (1.5 equiv, 158 mg, 0.83 mmol). The reaction was then stirred overnight. The reaction was then partitioned between EtOAc (5 mL) and H2O (5 mL). The organic phase was separated, dried over Na2SO4, filtered and concentrated. The residue was purified by trituration with Et2O to afford tert-butyl-1-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)cyclopropylcarbamate in 166 mg (65%). LRMS: 466.5 (calc) 489.3 (MNa)+.
Step 2: N-(1-aminocyclopropanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174a)




A 4M solution of HCl in dioxane (3 mL) was added to tert-butyl-1-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)cyclopropylcarbamate (166 mg, 0.36 mmol). The reaction was stirred for 1 h. The solvent was evaporated under reduced pressure. The compound was triturated with Et2O to afford N-(1-aminocyclopropanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride
(174a) in 142 mg (99%). (dDMSO) δ(ppm) 1H, 12.36 (bs, 1H), 8.82 (bs, 3H), 7.26-7.08 (m, 9H), 3.43 (s, 2H), 2.55 (m, 4H), 1.55-1.49 (m, 8H). LRMS: 366.1 (calc) 365.4 (MH)−.
Example 46
The following additional compounds were prepared by procedures analogous to those described in the Examples 40-43 and 45:
a) (S)—N-(2-amino-3-phenylpropanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174b)




(DMSO) δ(ppm) 1H, 12.39 (bs, 1H), 8.47 (bs, 3H), 7.31-6.96 (m, 1H), 4.54 (m, 1H), 3.46 (s, 2H), 3.15 (m, 2H), 2.56 (q, J=6.8, 13.6 Hz, 4H), 1.54 (m, 4H). LRMS(ESI): (calc.) 430.2 (found) 431.4 (MH)+.
b) (S)—N-(2-amino-3-methylbutanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174c)




(DMSO) δ(ppm) 1H, 12.32 (bs, 1H), 8.33 (bs, 3H), 7.24-7.09 (m, 9H), 4.13 (m, 1H), 3.45 (s, 2H), 2.57 (m, 4H), 2.18 (m, 1H), 1.55 (m, 4H), 1.03-0.94 (m, 6H). LRMS(ESI): (calc.) 382.2 (found) 383.1 (MH)+.
c) (S)—N-(2-amino-3,3-dimethylbutanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174d)




(dDMSO) δ(ppm) 1H, 12.49 (bs, 1H), 8.59 (bs, 3H), 7.26-7.09 (m, 9H), 3.98 (s, 1H), 3.47 (s, 2H), 2.56 (m, 4H), 1.55 (m, 4H), 1.05 (s, 9H). LRMS(ESI): (calc.) 396.2 (found) 397.5 (MH)+.
d) N-(1-aminocyclobutanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174e)




(dDMSO) δ(ppm) 1H, 12.52 (bs, 1H), 8.90 (bs, 1H), 7.19 (m, 9H), 3.47 (s, 2H), 2.56 (m, 6H), 2.05 (m, 2H), 1.54 (m, 4H). LRMS(ESI): (calc.) 380.2 (found) 381.4 (MH)+.
e) N-(2-amino-2-methylpropanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174f)




(dDMSO) δ(ppm) 1H, 12.45 (bs, 1H), 8.77 (bs, 3H), 7.16 (m, 9H), 3.45 (s, 2H), 2.56 (m, 4H), 1.54 (m, 10H). LRMS(ESI): (calc.) 368.2 (found) 369.4 (MH)+.
f) N-(1-(aminomethyl)cyclopropanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride (174 g)




(dDMSO) δ(ppm) 1H: 12.17 (bs, 1H), 8.00 (bs, 3H), 7.26-7.08 (m, 9H), 3.42 (s, 2H), 3.05 (s, 2H), 2.55 (m, 4H), 1.54 (m, 4H), 1.35 (m, 2H), 1.26 (m, 2H) LRMS(ESI): (calc.) 380.2 (found) 381.5 (MH)+
Example 47
The following additional prodrugs according to the present invention were also prepared.







Example 48
Inhibition of Histone Deacetylase Enzymatic Activity
HDAC inhibitors are screened against histone deacetylase enzyme in nuclear extracts prepared from the human small cell lung cancer cell line H446 (ATTC HTB-171) and against a cloned recombinant human (e.g., HDAC-1) enzyme expressed and purified from a Baculovirus insect cell expression system.
For deacetylase assays, 20,000 cpm of the [3H]-metabolically labeled acetylated histone substrate (M. Yoshida et al., J. Biol. Chem. 265(28): 17174-17179 (1990)) is incubated with 30 μg of H446 nuclear extract or an equivalent amount of the cloned recombinant hHDAC-1 for 10 minutes at 37° C. The reaction is stopped by adding acetic acid (0.04 M, final concentration) and HCl (250 mM, final concentration). The mixture is extracted with ethyl acetate and the released [3H]-acetic acid was quantified by scintillation counting. For inhibition studies, the enzyme is preincubated with compounds at 4° C. for 30 minutes prior to initiation of the enzymatic assay. IC50 values for HDAC enzyme inhibitors are determined by performing dose response curves with individual compounds and determining the concentration of inhibitor producing fifty percent of the maximal inhibition.
Alternatively (Table 4a), the following protocol is used to assay the compounds of the invention. In the assay, the buffer used is 25 mM HEPES, pH 8.0, 137 mM NaCl, 2.7 mM KCl, 1 mM MgCl2 and the substrate is Boc-Lys(Ac)-AMC in a 50 mM stock solution in DMSO. The enzyme stock solution is 4.08 μg/mL in buffer. The compounds are pre-incubated (2 μl in DMSO diluted to 13 μl in buffer for transfer to assay plate) with enzyme (20 μl of 4.08 μg/ml) for 10 minutes at room temperature (35 μl pre-incubation volume). The mixture is pre-incubated for 5 minutes at room temperature. The reaction is started by bringing the temperature to 37° C. and adding 16 μl substrate. Total reaction volume is 50 μl. The reaction is stopped after 20 minutes by addition of 50 μl developer, prepared as directed by Biomol (Fluor-de-Lys developer, Cat. # KI-105). A plate is incubated in the dark for 10 minutes at room temperature before reading (λEx=360 nm, λEm=470 nm, Cutoff filter at 435 nm).
Representative data are presented in Tables 4 and 4a. In the first column of Table 4 are reported IC50 values determined against histone deacetylase in nuclear extracts from H446 cells (pooled HDACs). In the second column of Table 4 are reported IC50 values determined against recombinant human HDAC-1 enzyme (rHDAC-1). For less active compounds, the data are expressed as the percent inhibition at the specified concentration.







TABLE 4







Inhibition of Histone Deacetylase














pooled






HDACs
rHDAC-1


Example
Cpd.
Structure
IC50 (μM)
IC50 (μM)














Ex. 1
4




7



 


Ex. 2
7




70



 


Ex. 3
8




15



 


Ex. 4
9




9



 


Ex. 5
10




30



 


Ex. 6
11




10



 


Ex. 7
12




3



 


Ex. 8
13




0.9



 


Ex. 9
14




36% @ 100 μM



 


Ex. 10
15




25



 


Ex. 11
16




38% 100 μM



 


Ex. 12
17




47% 100 μM



 


Ex. 13
18




160



 


Ex. 14
19




20



 


Ex. 15
26




<20



 


Ex. 16
32




<20



 


Ex. 17
34




2
0.3


 


Ex. 18
36




0.5
0.2


 


Ex. 19
38




0.75
0.1


 


Ex. 20
42




5
1.0


 


Ex. 21
45




4



 


Ex. 22
50




5



 


Ex. 23
53




25



 


Ex. 24
56




15



 


Ex. 25
61




4



 


Ex. 26
64




12% @ 100 μM



 


Ex. 27
68




3% @ 20 μM



 


Ex. 28
70




5.5
0.9


 


Ex. 28
71




44% @ 20 μM



 


Ex. 28
73




35% @ 20 μM



 


Ex. 29
77




 
0.65


 


Ex. 30
81




>50
>25


 


Ex. 31
86





3.8


 


Ex. 31
87




3
0.6


 


Ex. 31
88




0.6
0.075


 


Ex. 31
89




3
0.9


 


Ex. 31
90




0.4
0.09


 


Ex. 31
91




5
2


 


Ex. 31
92




>20
17


 


Ex. 31
93




0.35
0.05


 


Ex. 31
94




0.4
0.03


 


Ex. 31
95




0.8
0.2


 


Ex. 31
96




33% @ 5 μM



 


Ex. 31
97




0.8
0.28


 


Ex. 31
98




0.55
0.06


 


Ex. 31
99




0.9
0.05


 


Ex. 31
100




0.8
0.75


 


Ex. 31
101




0.3
0.04


 


Ex. 31
102




5.5
0.8


 


Ex. 31
103




0.7
0.05


 


Ex. 31
104




21% @ 5 μM



 


Ex. 31
105




0.55
0.2


 


Ex. 31
106




0.8
0.3


 


Ex. 31
107




0% @ 1 μM
5


 


Ex. 31
108




10% @ 1 μM
0.3


 


Ex. 31
109




32% @ 1 μM
0.12


 


Ex. 31
110




0.7
0.55


 


Ex. 31
111




0.4
0.095


 


Ex. 31
112




1.2
0.6


 


Ex. 31
113




46% @ 1 μM
0.2


 


Ex. 31
114




40% @ 1 μM
0.1


 


Ex. 31
115




53% @ 1 μM
0.1


 


Ex. 31
116





4


 


Ex. 31
117




0% @ 20 μM
1.9


 


Ex. 31
118




0% @ 20 μM
2.3


 


Ex. 31
119





3


 


Ex. 31
120




0.12
0.01


 


Ex. 31
121





23


 


Ex. 31
122





2.3


 


Ex. 31
123





1


 


Ex. 32
128





0.3


 


Ex. 32
129





3.0


 


Ex. 33
136




9
0.5


 


Ex. 34
139




44% @ 20 μM



 


Ex. 34
143




55% @ 20 μM
2.4


 


Ex. 34
144




6% @ 20 μM
6.9


 


Ex. 35
145




3.8
0.84


 


Ex. 35
146




2.9
0.91


 


Ex. 35
147




1.9
0.48


 


Ex. 36
148




5
2.0


 


Ex. 36
149




8% @ 20 μM
0.1


 


Ex. 36
150




10
1.0


 


Ex. 36
151




7.5
2.3


 


Ex. 36
152




35% @ 20 μM



 


Ex. 36
153




5
4.8


 


Ex. 36
154




 
0.9


 


Ex. 36
155




39% @ 20 μM



 


Ex. 36
156




5
0.75


 


Ex. 36
157




6
2.4


 


Ex. 36
158




>20



 


Ex. 36
159





1.5


 


Ex. 36
160





1.2


 


Ex. 36
161





0.05


 


Ex. 36
162





0.04


 


Ex. 37
164





5.0


 


Ex. 37
165





2.0


 


Ex. 37
166








 


Ex. 37
167








 


Ex. 38
168




0% @ 20 μM
3


 


Ex. 39
170




48% @ 2 μM
0.57


 



171




20



 



172




10



 



173




35% @ 20 μM



 



174




>20



 



175




>2 



 



176




20% @ 20 μM



 



177




10% @ 20 μM



 



178




2% @ 20 μM
>20



















TABLE 4a







rHDAC-1
rHDAC-8


Cpd.
Structure
IC50 (μM)
IC50 (μM)







182




0.7 PI (64%)
1.3 PI (74%)


 


179




0.5 
0.53


 


183




0.38
0.41


 


184




0.93
0.4 PI (79%)


 


185




0.84
0.61


 


187




0.2 PI (62%)
0.21





PI = partial inhibition (100% inhibition not reached-PI value indicates IC50 (at maximum % inhibition reached))






Example 49
Inhibition of Histone Deacetylase in Whole Cells
1. Histone H4 Acetylation in Whole Cells by Immunoblots
T24 human bladder cancer cells growing in culture are incubated with HDAC inhibitors for 16 hours. Histones are extracted from the cells after the culture period as described by M. Yoshida et al. (J. Biol. Chem. 265(28): 17174-17179 (1990)). 20 μμg of total histone protein are loaded onto SDS/PAGE and transferred to nitrocellulose membranes. Membranes are probed with polyclonal antibodies specific for acetylated histone H-4 (Upstate Biotech Inc.), followed by horse radish peroxidase conjugated secondary antibodies (Sigma). Enhanced Chemiluminescence (ECL) (Amersham) detection is performed using Kodak films (Eastman Kodak). Acetylated H-4 signal is quantified by densitometry.
Data for selected compounds are presented in Table 5. Data are presented as the concentration effective for reducing the acetylated H-4 signal by 50% (EC50).







TABLE 5







Inhibibition of Histone Acetylation in Cells











EC50


Cpd.
Structure
(μM)





 36




5


 


 90




1


 


 98




1


 


107




5


 


118




3


 


120




1


 


122




2









2. Acid Urea Triton (AUT) Gel Analysis of Histone Acetylation.

Human cancer cells (T24, 293T or Jurkat cells) growing in culture are incubated with HDAC inhibitors for 24 h. Histones are extracted from the cells as described by M. Yoshida et al. (J. Biol. Chem. 265(28): 17174-17179 (1990)). Acid urea triton (AUT) gel electrophoresis is used for detection of acetylated histone molecules. Histones (150 μμg of total protein) are electrophoresed at 80 V for 16 h at room temperature as described by M. Yoshida et al., supra. Gels are stained with Coomassie brilliant blue to visualize histones, dried and scanned by densitometry to quantified acetylation of histones.
Example 50
Antineoplastic Effect of Histone Deacetylase Inhibitors on Tumor Cells In Vivo
Eight to ten week old female BALB/c nude mice (Taconic Labs, Great Barrington, N.Y.) are injected subcutaneously in the flank area with 2×106 preconditioned A549 human lung carcinoma cells. Preconditioning of these cells is done by a minimum of three consecutive tumor transplantations in the same strain of nude mice. Subsequently, tumor fragments of approximately 30 mgs are excised and implanted subcutaneously in mice, in the left flank area, under Forene anesthesia (Abbott Labs, Geneve, Switzerland). When the tumors reach a mean volume of 100 mm3, the mice are treated intravenously, subcutaneously, or intraperitoneally by daily injection, with a solution of the histone deacetylase inhibitor in an appropriate vehicle, such as PBS, DMSO/water, or Tween 80/water, at a starting dose of 10 mg/kg. The optimal dose of the HDAC inhibitor is established by dose response experiments according to standard protocols. Tumor volume is calculated every second day post infusion according to standard methods (e.g., Meyer et al., Int. J. Cancer 43: 851-856 (1989)). Treatment with the HDAC inhibitors according to the invention causes a significant reduction in tumor weight and volume relative to controls treated with saline only (i.e., no HDAC inhibitor). In addition, the activity of histone deacetylase when measured is expected to be significantly reduced relative to saline treated controls.
Example 51
Synergistic Antineoplastic Effect of Histone Deacetylase Inhibitors and Histone Deacetylase Antisense Oligonucleotides on Tumor Cells In Vivo
The purpose of this example is to illustrate the ability of the histone deacetylase inhibitor of the invention and a histone deacetylase antisense oligonucleotide to synergistically inhibit tumor growth in a mammal. Preferably, the antisense oligonucleotide and the HDAC inhibitor inhibit the expression and activity of the same histone deacetylase.
As described in Example 10, mice bearing implanted A549 tumors (mean volume 100 mm3) are treated daily with saline preparations containing from about 0.1 mg to about 30 mg per kg body weight of histone deacetylase antisense oligonucleotide. A second group of mice is treated daily with pharmaceutically acceptable preparations containing from about 0.01 mg to about 5 mg per kg body weight of HDAC inhibitor.
Some mice receive both the antisense oligonucleotide and the HDAC inhibitor. Of these mice, one group may receive the antisense oligonucleotide and the HDAC inhibitor simultaneously intravenously via the tail vein. Another group may receive the antisense oligonucleotide via the tail vein, and the HDAC inhibitor subcutaneously. Yet another group may receive both the antisense oligonucleotide and the HDAC inhibitor subcutaneously. Control groups of mice are similarly established which receive no treatment (e.g., saline only), a mismatch antisense oligonucleotide only, a control compound that does not inhibit histone deacetylase activity, and a mismatch antisense oligonucleotide with a control compound.
Tumor volume is measured with calipers. Treatment with the antisense oligonucleotide plus the histone deacetylase protein inhibitor according to the invention causes a significant reduction in tumor weight and volume relative to controls.
Example 52
Solubility
The solubility of several compounds according to the invention was measured, and the results are displayed in the table below.










 








 









Solubility (μM)









Q
pH 2
Water*





H
 3
 3


 






 4
 5


 






132
195


 






 10
 9


 






>250 
>250 


 






142
136


 






186
130


 






 49



 






>2000
>1000


 






166
165





*Milli-Q ® purified water






While the invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as follows in the scope of the appended claims.

## Claims

1. A compound selected from the group consisting of
N-(1-aminocyclopropanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride;
(S)-N-(2-amino-3-phenylpropanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride;
(S)-N-(2-amino-3-methylbutanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride;
(S)-N-(2-amino-3,3-dimethylbutanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride;
N-(1-aminocyclobutanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride;
N-(2-amino-2-methylpropanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride;
N-(1-(aminomethyl)cyclopropanecarbonyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide hydrochloride;
(S)-N-(2,6-diaminohexanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide;
N-(2-hydroxyacetoxy)-2-(4-(4-phenylbutyl)phenyl)acetamide;
(S)-N-(2-amino-5-guanidinopentanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide;
(S)-2,6-diamino-N-(1-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)cyclopropyl)hexanamide;
N-(1-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)cyclopropyl)nicotinamide;
(S)-2-amino-3-methyl-N-(1-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)cyclopropyl)butanamide;
(S)-2-amino-3-phenyl-N-(1-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)cyclopropyl)propanamide;
2-(4-(4-phenylbutyl)phenyl)-N-((2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yloxy)acetamide; and
N-(2,3-dihydroxypropanoyloxy)-2-(4-(4-phenylbutyl)phenyl)acetamide.

2. A pharmaceutically acceptable salt of a species selected from the group consisting of
1-methyl-3-(3-oxo-3-(2-(4-(4-phenylbutyl)phenyl)acetamidooxy)propyl)pyridinium, 1-methyl-4-(3-oxo-3-(2-(4-(4-phenylbutyl)phenyl)acetamidooxy)propyl)-4H-1,2,4-triazol-1-ium, and
1-methyl-3-((2-(4-(4-phenylbutyl)phenyl)acetamidooxy)carbonyl)pyridinium.

3. A composition comprising a pharmaceutically acceptable salt of claim 1.