Abstract:
The present invention relates to ethynyl compounds of formula I 
     
       
                 
         
             
             
         
       
     
     wherein
   R1, R2, R2′, R3, R3′, R4, R4′, U, V, W, Y, m, and n are as defined herein and to a pharmaceutically acceptable acid addition salts, to a racemic mixtures, or to its corresponding enantiomers and/or optical isomers and/or stereoisomers thereof. Compounds of formula I are allosteric modulators of the metabotropic glutamate receptor subtype 5 (mGluR5).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a Divisional of U.S. patent application Ser. No. 13/779,782, filed Feb. 28, 2013, which is a Divisional of U.S. patent application Ser. No. 13/066,044, filed Apr. 5, 2011, now U.S. Pat. No. 8,420,661, which claims the benefit of European Patent Application No. 10159754.0, filed Apr. 13, 2010. Each of these applications is hereby incorporated by reference herein in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    In the central nervous system (CNS) the transmission of stimuli takes place by the interaction of a neurotransmitter, which is sent out by a neuron, with a neuroreceptor. 
         [0003]    Glutamate is the major excitatory neurotransmitter in the brain and plays a unique role in a variety of central nervous system (CNS) functions. The glutamate-dependent stimulus receptors are divided into two main groups. The first main group, namely the ionotropic receptors, forms ligand-controlled ion channels. The metabotropic glutamate receptors (mGluR) belong to the second main group and, furthermore, belong to the family of G-protein coupled receptors. 
         [0004]    At present, eight different members of these mGluR are known and of these some even have sub-types. According to their sequence homology, signal transduction mechanisms and agonist selectivity, these eight receptors can be sub-divided into three sub-groups: 
         [0000]    mGluR1 and mGluR5 belong to group I, mGluR2 and mGluR3 belong to group II and mGluR4, mGluR6, mGluR7 and mGluR8 belong to group III. 
         [0005]    Ligands of metabotropic glutamate receptors belonging to the first group can be used for the treatment or prevention of acute and/or chronic neurological disorders such as psychosis, epilepsy, schizophrenia, Alzheimer&#39;s disease, cognitive disorders and memory deficits, as well as chronic and acute pain. 
         [0006]    Other treatable indications in this connection are restricted brain function caused by bypass operations or transplants, poor blood supply to the brain, spinal cord injuries, head injuries, hypoxia caused by pregnancy, cardiac arrest and hypoglycaemia. Further treatable indications are ischemia, Huntington&#39;s chorea, amyotrophic lateral sclerosis (ALS), dementia caused by AIDS, eye injuries, retinopathy, idiopathic parkinsonism or parkinsonism caused by medicaments as well as conditions which lead to glutamate-deficiency functions, such as e.g. muscle spasms, convulsions, migraine, urinary incontinence, nicotine addiction, opiate addiction, anxiety, vomiting, dyskinesia and depressions. 
         [0007]    Disorders mediated full or in part by mGluR5 are for example acute, traumatic and chronic degenerative processes of the nervous system, such as Alzheimer&#39;s disease, senile dementia, Parkinson&#39;s disease, Huntington&#39;s chorea, amyotrophic lateral sclerosis and multiple sclerosis, psychiatric diseases such as schizophrenia and anxiety, depression, pain and drug dependency ( Expert Opin. Ther. Patents  (2002), 12, (12)). 
         [0008]    A new avenue for developing selective modulators is to identify compounds which act through allosteric mechanism, modulating the receptor by binding to a site different from the highly conserved orthosteric binding site. Allosteric modulators of mGluR5 have emerged recently as novel pharmaceutical entities offering this attractive alternative. Allosteric modulators have been described, for example in WO2008/151184, WO2006/048771, WO2006/129199 and WO2005/044797 and in  Molecular Pharmacology,  40, 333-336, 1991;  The Journal of Pharmacology and Experimental Therapeutics, Vol  313, No. 1, 199-206, 2005; 
         [0009]    In recent years there have been significant advantages in understanding the pathophysiology of several disorders of brain development, suggesting that protein synthesis at synapses is triggered by activation of group I metabotropic glutamate receptors. Such disorders include fragile X syndrome, autism, idiopatic autism, tuberous sclerosis complex disorder, neurofibromatosis type 1 or Rett syndrome ( Annu. Rev. Med.,  2011, 62, 31.1-31.19 and  Neuroscience  156, 2008, 203-215). 
         [0010]    Described in the prior art are positive allosteric modulators. They are compounds that do not directly activate receptors by themselves, but markedly potentiate agonist-stimulated responses, increase potency and maximum of efficacy. The binding of these compounds increases the affinity of a glutamate-site agonist at its extracellular N-terminal binding site. Allosteric modulation is thus an attractive mechanism for enhancing appropriate physiological receptor activation. There is a scarcity of selective allosteric modulators for the mGluR5 receptor. Conventional mGluR5 receptor modulators typically lack satisfactory aqueous solubility and exhibit poor oral bioavailability. 
         [0011]    Therefore, there remains a need for compounds that overcome these deficiencies and that effectively provide selective allosteric modulators for the mGluR5 receptor. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention provides ethynyl compounds of formula I 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen,   
       R 5  is hydrogen, methyl or halogen;   Y is —N(R 6 )—, —O—, —C(R 7′ )(R 7 )—, —CH 2 O— or —CH 2 S(O) 2 —;
       wherein R 6  is hydrogen or lower alkyl and R 7  and R 7′  are each independently hydrogen, hydroxy, lower alkyl or lower alkoxy;   
       R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing —CH 2 OCH 2 —;   m is 0, 1 or 2;
       when m is 1,   
       R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;
       or R 3  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group or a ring containing —(CH 2 ) 2 OCH 2 —;   
       n is 0 or 1; and
       when n is 1,   
       R 4  and R 4′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl; or
       R 4  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group;
 
or when n is 0 and Y is —N(R 6 )—, then R 6  and R 2  together with the carbon atom and the nitrogen atom to which they are attached form a C 3-6 -cycloalkyl group;
 
or when n and m are 0, then R 2  and R 7  together with the carbon atoms to which they are attached form a C 3-6 -cycloalkyl group;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an isomer, and/or a stereoisomer thereof.
   
       
 
         [0030]    The present invention provides compounds of formula I per se, their pharmaceutically acceptable salts, and mixtures of enantiomers or diastereomers or their enantiomerically or diastereomerically pure forms. The invention also provides pharmaceutical compositions containing a therapeutically effective amount of such compounds and process for the production of such compounds and compositions. 
         [0031]    Compounds of formula I are allosteric modulators of the metabotropic glutamate receptor subtype 5 (mGluR5). They can be used in the treatment or prevention of disorders relating to allosteric modulators for the mGluR5 receptor. For example, the compounds can be used for the treatment or prevention of disorders, relating to allosteric modulators for the mGluR5 receptor, such as schizophrenia, cognition, fragile X syndrome or autism, and to pharmaceutical compositions containing the compounds of formula I. The most preferred indications are schizophrenia and cognition. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    The following definitions of the general terms used in the present description apply irrespective of whether the terms in question appear alone or in combination. 
         [0033]    As used herein, the term “lower alkyl” denotes a saturated, i.e. aliphatic hydrocarbon group including a straight or branched carbon chain with 1-4 carbon atoms. Examples for “alkyl” are methyl, ethyl, n-propyl, and isopropyl. 
         [0034]    The term “lower alkoxy” denotes a group —O—R′ wherein R′ is lower alkyl as defined above. 
         [0035]    The term “halogen” denotes the chlorine, fluorine, bromine, or iodine. 
         [0036]    The term “ethynyl” denotes the group —C≡C—. 
         [0037]    The term “cycloalkyl” denotes a saturated carbon ring, containing from 3 to 6 carbon ring atoms, for example cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl. 
         [0038]    The term “heteroaryl” denotes a 5 or 6-membered aromatic ring, containing at least one N, O or S-heteroatom, for example pyridinyl, pyrimidinyl, pyrazolyl, pyridazinyl, imidazolyl, triazolyl, thienyl or pyrazinyl. 
         [0039]    “Pharmaceutically acceptable,” such as pharmaceutically acceptable carrier, excipient, etc., denotes pharmacologically acceptable and substantially non-toxic to the subject to which the particular compound is administered. 
         [0040]    The term “pharmaceutically acceptable salt” or “pharmaceutically acceptable acid addition salt” embraces salts with inorganic and organic acids, such as hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, citric acid, formic acid, fumaric acid, maleic acid, acetic acid, succinic acid, tartaric acid, methane-sulfonic acid, p-toluenesulfonic acid and the like. 
         [0041]    “Therapeutically effective amount” denotes an amount that is effective to prevent, alleviate or ameliorate symptoms of disease or prolong the survival of the subject being treated. 
         [0042]    One embodiment of the invention provides compounds of formula I-1 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen.   
       R 5  is hydrogen, methyl or halogen;   R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing —CH 2 OCH 2 —; and   R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;
       or R 3  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group or a ring containing —(CH 2 ) 2 OCH 2 —;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an optical isomer, and/or stereoisomer thereof.
   
       
 
         [0052]    Examples of compounds of formula I-A1 are the following:
   3-(3-fluoro-5-phenylethynyl-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one;   (5RS)-5-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   (5R or 5S)-5-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   (5S or 5R)-5-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   5,5-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   3-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one;   5,5-dimethyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-oxazolidin-2-one;   (5RS)-5-tert-butyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   6-(5-phenylethynyl-pyridin-2-yl)-4-oxa-6-aza-spiro[2.4]heptan-5-one;   7-(5-phenylethynyl-pyridin-2-yl)-5-oxa-7-aza-spiro[3.4]octan-6-one;   3-(5-phenylethynyl-pyridin-2-yl)-1-oxa-3-aza-spiro[4.4]nonan-2-one;   3-(5-phenylethynyl-pyridin-2-yl)-1-oxa-3-aza-spiro[4.5]decan-2-one;   (5RS)-5-tert-butyl-5-methyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   (3aRS,6aSR)-3-(5-phenylethynyl-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one;   (3aRS,6aSR)-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one;   (3aRS,6aSR)-3-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-hexahydro-cyclopentaoxazol-2-one;   (RS)-4,5,5-trimethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   4,4,5,5-tetramethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   3-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one;   5,5-dimethyl-3-(5-pyrimidin-5-ylethynyl-pyridin-2-yl)-oxazolidin-2-one;   5,5-dimethyl-3-[5-(1-methyl-1H-pyrazol-4-ylethynyl)-pyridin-2-yl]-oxazolidin-2-one;   3-[5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one;   3-[5-(3,4-difluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one;   3-[5-(2,5-difluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one;   3-[5-(6-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one;   6-(5-pyridin-3-ylethynyl-pyridin-2-yl)-4-oxa-6-aza-spiro[2.4]heptan-5-one;   (6SR,7RS)-3-(5-phenylethynyl-pyridin-2-yl)-hexahydro-benzooxazol-2-one;   (3aSR,7aRS)-(3 aRS,7RS)-1-(5-phenylethynyl-pyridin-2-yl)-hexahydro-pyrano[4,3-d]oxazol-2-one; and   5,5-dimethyl-3-(6-(phenylethynyl)pyridazin-3-yl)oxazolidin-2-one.   
 
         [0082]    A further embodiment of the invention provides compounds of formula I-B1 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen.   
       R 5  is hydrogen, methyl or halogen;   R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing
       —CH 2 OCH 2 —;   
       R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group; or R 3  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group or a ring containing —(CH 2 ) 2 OCH 2 —; and   R 7  and R 7′  are each independently hydrogen, hydroxy, lower alkyl or lower alkoxy;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an optical isomer, and/or stereoisomer thereof.
   
 
         [0093]    Specific examples of compounds of formula I-B1 are the following:
   4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one;   (3RS)-3-hydroxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one;   1-(3-fluoro-5-phenylethynyl-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one;   1-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one;   4,4-dimethyl-1-(5-pyridin-3-ylethynyl-pyridin-2-yl)-pyrrolidin-2-one;   1-[5-(5-chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one;   1-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one;   4,4-dimethyl-1-(3-methyl-5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one;   2-(5-phenylethynyl-pyridin-2-yl)-2-aza-spiro[4.4]nonan-3-one;   (RS)-3-methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one;   (5R or 5S)-5-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   (5S or 5R)-5-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one;   (RS)-1-[5-(5-chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one;   (RS)-3-methoxy-4,4-dimethyl-1-(5-m-tolylethynyl-pyridin-2-yl)-pyrrolidin-2-one;   (RS)-1-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one;   (RS)-1-[5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one;   6-(5-phenylethynyl-pyridin-2-yl)-2-oxa-6-aza-spiro[3.4]octan-7-one;   4,4-dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   5′-(3-fluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   5′-(3-chloro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   5′-(5-chloro-pyridin-3-ylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   5′-(4-fluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   5′-(2,5-difluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one;   2-(5-phenylethynyl-pyrimidin-2-yl)-2-aza-spiro[4.4]nonan-3-one;   1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one;   1-[5-(3-chloro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one;   1-[5-(4-fluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one;   1-[5-(2,5-difluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one;   (RS)-3-methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one;   (5R or 5S)-5-methoxymethyl-3-(5-phenylethynyl-pyrimidin-2-yl)-oxazolidin-2-one;   (5S or 5R)-5-methoxymethyl-3-(5-phenylethynyl-pyrimidin-2-yl)-oxazolidin-2-one;   (RS)-1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one;   (R or S)-1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one;   (S or R)-1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one;   (R or S)-1-[5-(2,5-difluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one;   4,4-dimethyl-1-(6-(phenylethynyl)pyridazin-3-yl)pyrrolidin-2-one; and   4,4-dimethyl-1-(5-(pyridin-3-ylethynyl)pyrazin-2-yl)pyrrolidin-2-one.   
 
         [0132]    A further embodiment of the invention provides compounds of formula I-C1 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen.   
       R 5  is hydrogen, methyl or halogen;   R 6  is hydrogen or lower alkyl;   R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing —CH 2 OCH 2 —; and   R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;
       or R 3  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group or a ring containing —(CH 2 ) 2 OCH 2 —;   
       Or R 6  and R 2  together with the carbon atom and the nitrogen atom to which they are attached form a C 3-6 -cycloalkyl;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an optical isomer and/or stereoisomer thereof.
   
 
         [0144]    Examples of compounds of formula I-C1 are the following:
   4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one;   3,4,4-trimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one;   3-ethyl-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one;   3-isopropyl-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one;   1-methyl-3-(5-phenylethynyl-pyridin-2-yl)-1,3-diaza-spiro[4.4]nonan-2-one;   (RS)-4-cyclopentyl-3-methyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one;   3,4,4-trimethyl-1-(5-pyridin-3-ylethynyl-pyridin-2-yl)-imidazolidin-2-one;   1-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   3,4,4-trimethyl-1-[5-(1-methyl-1H-pyrazol-4-ylethynyl)-pyridin-2-yl]-imidazolidin-2-one;   1-[5-(5-chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   3,4,4-trimethyl-1-(5-pyridazin-4-ylethynyl-pyridin-2-yl)-imidazolidin-2-one;   1-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   1-[5-(3-chloro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   3,4,4-trimethyl-1-(5-pyrimidin-5-ylethynyl-pyridin-2-yl)-imidazolidin-2-one;   3,4,4-trimethyl-1-(5-m-tolylethynyl-pyridin-2-yl)-imidazolidin-2-one;   1-[5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   (RS)-2-(5-phenylethynyl-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one;   (RS)-2-(5-pyridin-3-ylethynyl-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one;   (RS)-2-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-hexahydro-imidazo[1,5-a]pyridin-3-one;   (RS)-4-cyclopropyl-3-methyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one;   (3aSR,7aRS)-(3 aRS,7RS)-1-methyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one;   (3aSR,7aRS)-(3 aRS,7RS)-1-methyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one;   (3aSR,7aRS)-(3 aRS,7RS)-1-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-3-methyl-octahydro-benzoimidazol-2-one;   4-methyl-6-(5-phenylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one;   (3aSR,7aRS)-(3 aRS,7RS)-1-ethyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one;   (3aSR,7aRS)-(3 aRS,7RS)-1-ethyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one;   (3aSR,7aRS)-(3 aRS,7RS)-1-isopropyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one;   (3aRS, 6aSR)-1-methyl-3-(5-(phenylethynyl) pyridin-2-yl)hexahydrocyclopenta[d]imidazol-2(1H)-one;   (RS)-4-tert-butyl-3-methyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one;   1-[5-(3-fluoro-phenylethynyl)-3-methyl-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   (3aSR,6aRS)-1-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-3-methyl-hexahydro-cyclopenta-imidazol-2-one;   1-[3-fluoro-5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   1-[3-fluoro-5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   6-[5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-4-methyl-4,6-diaza-spiro[2.4]heptan-5-one;   6-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-4-methyl-4,6-diaza-spiro[2.4]heptan-5-one;   3,4,4-trimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-imidazolidin-2-one;   1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   1-[5-(2,5-difluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   1-[5-(4-fluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   1-[5-(3,4-di-fluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one;   3-isopropyl-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-imidazolidin-2-one;   1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-isopropyl-4,4-dimethyl-imidazolidin-2-one;   1-[5-(4-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-isopropyl-4,4-dimethyl-imidazolidin-2-one;   1-[5-(4-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-ethyl-4,4-dimethyl-imidazolidin-2-one;   1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-ethyl-4,4-dimethyl-imidazolidin-2-one;   4-methyl-6-(5-phenylethynyl-pyrimidin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one;   3,4,4-trimethyl-1-(6-(m-tolylethynyl)pyridazin-3-yl)imidazolidin-2-one;   1-(6-((3-chlorophenyl)ethynyl)pyridazin-3-yl)-3,4,4-trimethylimidazolidin-2-one;   3,4,4-trimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)imidazolidin-2-one;   3,4,4-trimethyl-1-(5-(pyridin-3-ylethynyl)pyrazin-2-yl)imidazolidin-2-one;   1-(5-((3-fluorophenyl)ethynyl)pyrazin-2-yl)-3,4,4-trimethylimidazolidin-2-one;   1-(5-((4-fluorophenyl)ethynyl)pyrazin-2-yl)-3,4,4-trimethylimidazolidin-2-one;   (3aRS,6aSR)-1-methyl-3-(6-phenylethynyl-pyridazin-3-yl)-hexahydro-cyclopentaimidazol-2-one; and   (3aSR,6aRS)-1-[6-(3-fluoro-phenylethynyl)-pyridazin-3-yl]-3-methyl-hexahydro-cyclopentaimidazol-2-one.   
 
         [0199]    A further embodiment of the invention provides compounds of formula I-D1 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen.   
       R 5  is hydrogen, methyl or halogen;   R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing —CH 2 OCH 2 —;   R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group; or R 3  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group or a ring containing —(CH 2 ) 2 OCH 2 —; and   R 4  and R 4′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached from a C 3 -C 6 -cycloalkyl;   R 4  and R 4′  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an optical isomer and/or stereoisomer thereof.
   
 
         [0210]    Examples of compounds of formula I-D1 are the following:
   5,5-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   6,6-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   6,6-dimethyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   3-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one;   3-[5-(5-chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one;   3-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one;   3-[5-(3-chloro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one;   6,6-dimethyl-3-(5-m-tolylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   3-[5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one;   3-[5-(3,4-difluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one;   3-[5-(2,5-difluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one;   7,7-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazepan-2-one;   (RS)-5-hydroxy-6,6-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   (4aRS,7aSR)-3-(5-phenylethynyl-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one;   (4aRS,7aRS)-3-(5-phenylethynyl-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one;   (RS)-5,6,6-trimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   (RS)-6-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   (RS)-5-methoxy-6,6-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one;   (RS)-5,6,6-trimethyl-3-(5-phenylethynyl-pyrimidin-2-yl)-[1,3]oxazinan-2-one;   (RS)-3-[5-(2,5-difluoro-phenylethynyl)-pyrimidin-2-yl]-5,6,6-trimethyl-[1,3]oxazinan-2-one;   (RS)-3-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-5,6,6-trimethyl-[1,3]oxazinan-2-one;   (RS)-3-[5-(4-fluoro-phenylethynyl)-pyrimidin-2-yl]-5,6,6-trimethyl-[1,3]oxazinan-2-one;   6,6-dimethyl-3-(6-(phenylethynyl)pyridazin-3-yl)-1,3-oxazinan-2-one;   6,6-dimethyl-3-(5-(phenylethynyl)pyrazin-2-yl)-1,3-oxazinan-2-one; and   (RS)-3-[5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-5-methoxy-6,6-dimethyl-[1,3]oxazinan-2-one.   
 
         [0236]    A further embodiment of the invention provides compounds of formula I-E1 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen.   
       R 5  is hydrogen, methyl or halogen;   R 7  and R 7′  are each independently hydrogen, hydroxy, lower alkyl or lower alkoxy;   R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing
       —CH 2 OCH 2 —;   
       R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;
       or R 3  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group or a ring containing —(CH 2 ) 2 OCH 2 —; and   
       R 4  and R 4′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;   R 4  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an optical isomer and/or stereoisomer thereof.
   
 
         [0250]    Specific examples of compounds of formula I-E1 are the following:
   5,5-dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   5′-(3-fluoro-phenylethynyl)-5,5-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one;   5,5-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-piperidin-2-one;   4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-piperidin-2-one;   1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-piperidin-2-one;   1-[5-(2,5-difluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-piperidin-2-one;   4,4-dimethyl-1-(6-(phenylethynyl)pyridazin-3-yl)piperidin-2-one;   1-(5-((3-fluorophenyl)ethynyl)pyrazin-2-yl)-4,4-dimethylpiperidin-2-one;   4,4-dimethyl-1-(5-(pyridin-3-ylethynyl)pyrazin-2-yl)piperidin-2-one; and   4,4-dimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)piperidin-2-one.   
 
         [0261]    A further embodiment of the invention provides compounds of formula I-F1 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen.   
       R 5  is hydrogen, methyl or halogen;   R 6  is hydrogen or lower alkyl;   R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing
       —CH 2 OCH 2 —;   
       R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;
       or R 3  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl group or a ring containing —(CH 2 ) 2 OCH 2 —; and   
       R 4  and R 4′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group; or   R 4  and R 2  together with the carbon atom to which they are attached form a C 3-6 -cycloalkyl;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an optical isomer and/or stereoisomer thereof.
   
 
         [0275]    Examples of compounds of formula I-F1 are the following:
   5,5-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one;   1,5,5-trimethyl-3-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one;   3,4,4-trimethyl-1-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one;   1-[5-(2,5-difluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one;   1-[5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one;   3,4,4-trimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one;   5′-(3-fluoro-phenylethynyl)-3,4,4-trimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one;   5′-(2,5-difluoro-phenylethynyl)-3,4,4-trimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one;   4,4-dimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)tetrahydropyrimidin-2(1H)-one;   3,4,4-trimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)tetrahydropyrimidin-2(1H)-one;   1-(5-((3-fluorophenyl)ethynyl)pyrazin-2-yl)-4,4-dimethyltetrahydropyrimidin-2(1H)-one; and   1-(5-((3-fluorophenyl)ethynyl)pyrazin-2-yl)-3,4,4-trimethyltetrahydropyrimidin-2(1H)-one.   
 
         [0288]    A further embodiment of the invention provides compounds of formula I-G1 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   U is ═N— or ═C(R 5 )—;   V is —CH═ or —N═;   W is ═CH— or ═N—;
       with the proviso that only one of U, V or W is nitrogen.   
       R 5  is hydrogen, methyl or halogen;   Y is —N(R 6 )—, —O—, —C(R 7′ )(R 7 )—, —CH 2 O— or —CH 2 S(O) 2 —;
       wherein R 6  is hydrogen or lower alkyl and R 7  and R 7′  are each independently hydrogen, hydroxy, lower alkyl and lower alkoxy;   
       R 1  is phenyl or heteroaryl, each of which is optionally substituted by one or two substituents, selected from halogen, lower alkyl and lower alkoxy; and   R 2  and R 2′  are each independently hydrogen, lower alkyl, hydroxy, lower alkoxy, C 3 -C 6 -cycloalkyl, or CH 2 -lower alkoxy, or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group or a ring containing
       —CH 2 OCH 2 —;   
       or R 6  and R 2  together with the carbon atom and the nitrogen atom to which they are attached form a C 3-6 -cycloalkyl group;   or R 2  and R 7  together with the carbon atoms to which they are attached form a C 3-6 -cycloalkylgroup;
 
or a pharmaceutically acceptable acid addition salt, a racemic mixture, an enantiomer, an optical isomer and/or stereoisomer thereof.
   
 
         [0301]    Examples of compounds of formula I-G1 are the following:
   (1 RS,5 SR)-6-(5-phenylethynyl-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one;   3,3-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-azetidin-2-one; and   (1RS,5SR)-6-(5-pyridin-3-ylethynyl-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one.   
 
         [0305]    The invention further provides compounds of formula I, wherein Y is —CH 2 O—, for example
   (RS)-6-methyl-4-(5-phenylethynyl-pyridin-2-yl)-morpholin-3-one and   6,6-dimethyl-4-(5-phenylethynyl-pyridin-2-yl)-morpholin-3-one.   
 
         [0308]    The invention further provides compounds of formula I, wherein Y is —CH 2 S(O) 2 —, for example 1,1-dioxo-4-(5-phenylethynyl-pyridin-2-yl)-thiomorpholin-3-one. 
         [0309]    The invention also provides compounds of formula I, wherein m is 2, for example 7,7-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazepan-2-one. 
         [0310]    The invention provides ethynyl compounds of formula Ia 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein
   X is N or C—R 5 ,
       wherein R 5  is hydrogen or halogen;   
       Y is N—R 6 , O or CHR 7 ,
       wherein R 6  is hydrogen or lower alkyl and R 7  is hydrogen, hydroxy, lower alkyl or lower alkoxy;   
       R 1  is phenyl or heteroaryl, each of which is optionally substituted by halogen, lower alkyl or lower alkoxy;   R 2  and R 2′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;   m is 0 or 1; when m is 1,   R 3  and R 3′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group; and   n is 0 or 1; when n is 1,   R 4  and R 4′  are each independently hydrogen, lower alkyl, or CH 2 -lower alkoxy or together with the carbon atom to which they are attached form a C 3 -C 6 -cycloalkyl group;   or when m is 1 and n is O, R 3  and R 2  together with the carbon atoms to which they are attached form a C 3-6 -cycloalkyl group;   or when m is 0 and m is 1, R 4  and R 2  together with the carbon atoms to which they are attached form a C 3-6 -cycloalkyl group;
 
or a pharmaceutically acceptable acid addition salt, racemic mixture, an enantiomer, an optical isomer, and/or stereoisomer thereof.
   
 
         [0323]    The preparation of compounds of formula I of the present invention can be carried out in sequential or convergent synthetic routes. Syntheses of the compounds of the invention are shown in the following schemes 1 to 3. The skills required for carrying out the reaction and purification of the resulting products are known to those skilled in the art. The substituents and indices used in the following description of the processes have the significance given herein before. 
         [0324]    The compounds of formula I can be manufactured by the methods given below, by the methods given in the examples or by analogous methods. Appropriate reaction conditions for the individual reaction steps are known to a person skilled in the art. The reaction sequence is not limited to the one displayed in the schemes, however, depending on the starting materials and their respective reactivity the sequence of reaction steps can be freely altered. Starting materials are either commercially available or can be prepared by methods analogous to the methods given below, by methods described in references cited in the description or in the examples, or by methods known in the art. 
         [0325]    The present compounds of formula I and their pharmaceutically acceptable salts can be prepared by methods, known in the art, for example by the process variant described below, which process comprises reacting a compound of formula 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein X is a suitable leaving group which can be substituted by an acetylene moiety such as, for example a bromine or iodine atom, a trialkylstannyl group, a boronic acid or boronic ester group with a suitable aryl-acetylene of formula 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    to obtain a compound of formula 
         [0000]    
       
                 
         
             
             
         
       
     
         [0000]    wherein the substituents are described above, or
 
if desired, converting the compounds obtained into pharmaceutically acceptable acid addition salts.
 
         [0326]    The preparation of compounds of formula I is further described in more detail in schemes 1 to 6 and in examples 1-174. 
         [0000]    
       
                 
         
             
             
         
       
     
         [0327]    A ethynyl-pyridine, ethynyl-pyrimidine, ethynyl-pyrazine or ethynyl-pyridazine compound of formula I-A can be obtained by substitution of an appropriate 5-iodo-2-fluoro-pyridine, 5-iodo-2-fluoro-pyrimidine, 2-chloro-5-iodopyridazine or 2-bromo-5-iodopyrazine 1 or the like and an appropriate aminoalcohol 2 with a base such as pyridine, triethylamine, or cesium carbonate in a solvent such as NMP, pyridine, or dioxane to yield the corresponding 5-iodo-2-aminoalkoxy-adducts of formula 3, which are treated with phosgene or a phosgene equivalent such as triphosgene in presence of base such as pyridine in a solvent like dichloromethane to give the corresponding cyclized urethane- or urea-derivatives 4. Sonogashira coupling of the iodo-heteroaryl derivatives 4 with an appropriately substituted arylacetylene 5 yield the desired ethynyl compounds of general formula I-A or I-D (scheme 1). 
         [0000]    
       
                 
         
             
             
         
       
     
         [0328]    An ethynyl-pyridine, ethynyl-pyrimidine, ethynyl-pyrazine or ethynyl-pyridazine compound of formula I-B can be obtained by reacting an appropriate 5-iodo-2-amino-pyridine- or 5-iodo-2-amino-pyrimidine-, 5-iodo-2-amino-pyrazine, or 5-iodo-2-amino-pyridazine derivative 6 or the like with an appropriately substituted anhydride 7 in a solvent such as DMF to yield the corresponding imide derivative 8, which is reduced with a reducing agent such as sodium borohydride in a solvent such as THF and/or MeOH to give the corresponding alcohol derivative 9. Reacting compound 9 with trifluoroacetic anhydride in a solvent like dichloromethane followed by reduction with triethylsilane in a solvent like TFA yields the desired amide 10. Sonogashira coupling of the amide 10 with an appropriately substituted aryl-acetylene 5 yields the desired ethynyl-compounds of formula I-B or I-E (scheme 2). 
         [0000]    
       
                 
         
             
             
         
       
     
         [0329]    An ethynyl-pyridine, ethynyl-pyrimidine, ethynyl-pyrazine or ethynyl-pyridazine compound of formula I-C can be obtained by substitution of an appropriate 5-iodo-2-fluoro-pyridine, 5-iodo-2-fluoro-pyrimidine, 2-chloro-5-iodopyridazine or 2-bromo-5-iodopyrazine 1 or the like (1) wherein Y is a suitable leaving group which can be displaced via nucleophillic substitution by an amine such as a fluorine, chlorine, or bromine atom or an alkysulfonyl group with an appropriate diaminoalkyl derivative 11 in presence of a base such as pyridine or cesium carbonate in a solvent like NMP, pyridine, or dioxane to yield the corresponding N-heteroaryl derivative 12, which is cyclized with phosgene or a phosgene equivalent in presence of a base such as pyridine or triethylamine in a solvent like dichloromethane or THF to give the corresponding urea derivative 13 which is then coupled with an appropriately substituted aryl-acetylene 5 to yield the desired ethynyl-compound of formula I-C or I-F (scheme 3). 
         [0000]    
       
                 
         
             
             
         
       
     
         [0330]    An ethynyl-pyridine or ethynyl-pyrimidine compound of formula I can be obtained for example by Sonogashira coupling of a 2-bromo-5-iodo-pyridine, 2-bromo-5-iodo-pyrimidine, 2-bromo-5-iodopyridazine or 2-bromo-5-iodopyrazine 1 or the like with ethynyltrimethylsilane 15 to yield the 2-bromo-5-trimethylsilanylethynyl-substituted heteroaryl derivatives 16. Substitution of 16 with an appropriate lactam, cyclic carbamate or cyclic urea derivative 17 in presence of a base such as cesium carbonate, or using xantphos and Pd 2 (dba) 3  in a solvent like toluene yields the corresponding 5-trimethylsilanylethynyl derivatives 18. Sonogashira coupling with in-situ desilylation of 18 in presence of fluoride and an appropriately substituted aryl-halogenide 19 yields the desired arylethynyl-compounds of formula I (scheme 4). 
         [0000]    
       
                 
         
             
             
         
       
     
         [0331]    An arylethynyl compound of formula I can be obtained by Sonogashira coupling of a 5-bromo- or 5-iodo-heteroaryl derivative 4, 10 or 13 (where Y═Br, I) with ethynyltrimethylsilane 15 to yield the corresponding 5-trimethylsilanylethynyl-derivatives 18. Sonogashira coupling with in-situ desilylation of 18 and an appropriately substituted aryl-halogenide 19 yields the desired ethynyl-pyridine or ethynyl-pyrimidine compounds of formula I (scheme 5). 
         [0332]    Generally speaking, the sequence of steps used to synthesize the compounds of formula I can also be modified in certain cases, for example by first running the Sonogashira coupling with an appropriately substituted aryl- or heteroaryl-ethynyl derivative followed by the introduction of a lactam-, cyclic carbamate- or cyclic urea using procedures similar to those described in schemes 1 to 4. (scheme 6) 
         [0000]    
       
                 
         
             
             
         
       
     
         [0333]    The compound of formula I as described herein as well as its pharmaceutically acceptable salt is used in the treatment or prevention of psychosis, epilepsy, schizophrenia, Alzheimer&#39;s disease, cognitive disorders and memory deficits, chronic and acute pain, restricted brain function caused by bypass operations or transplants, poor blood supply to the brain, spinal cord injuries, head injuries, hypoxia caused by pregnancy, cardiac arrest and hypoglycaemia, ischemia, Huntington&#39;s chorea, amyotrophic lateral sclerosis (ALS), dementia caused by AIDS, eye injuries, retinopathy, idiopathic parkinsonism or parkinsonism caused by medicaments, muscle spasms, convulsions, migraine, urinary incontinence, gastrointestinal reflux disorder, liver damage or failure whether drug or disease induced, Fragile-X syndrom, Down syndrom, autism, nicotine addiction, opiate addiction, anxiety, vomiting, dyskinesia, eating disorders, in particular bulimia or anorexia nervosa, and depressions, particularly for the treatment and prevention of acute and/or chronic neurological disorders, anxiety, the treatment of chronic and acute pain, urinary incontinence and obesity. 
         [0334]    The preferred indications are schizophrenia and cognitive disorders. 
         [0335]    Present invention further relates to the use of a compound of formula I as described herein, as well as its pharmaceutically acceptable salt, for the manufacture of a medicament, preferably for the treatment and prevention of the above-mentioned disorders. 
       Biological Assay and Data 
     Intracellular Ca 2+  Mobilization Assay 
       [0336]    A monoclonal HEK-293 cell line stably transfected with a cDNA encoding for the human mGlu5a receptor was generated; for the work with mGlu5 Positive Allosteric Modulators (PAMs), a cell line with low receptor expression levels and low constitutive receptor activity was selected to allow the differentiation of agonistic versus PAM activity. Cells were cultured according to standard protocols (Freshney, 2000) in Dulbecco&#39;s Modified Eagle Medium with high glucose supplemented with 1 mM glutamine, 10% (vol/vol) heat-inactivated bovine calf serum, Penicillin/Streptomycin, 50 μg/ml hygromycin and 15 μg/ml blasticidin (all cell culture reagents and antibiotics from Invitrogen, Basel, Switzerland). 
         [0337]    About 24 hrs before an experiment, 5×10 4  cells/well were seeded in poly-D-lysine coated, black/clear-bottomed 96-well plates. The cells were loaded with 2.5 μM Fluo-4AM in loading buffer (1×HBSS, 20 mM HEPES) for 1 hr at 37° C. and washed five times with loading buffer. The cells were transferred into a Functional Drug Screening System 7000 (Hamamatsu, Paris, France), and 11 half logarithmic serial dilutions of test compound at 37° C. were added and the cells were incubated for 10-30 min. with on-line recording of fluorescence. Following this pre-incubation step, the agonist L-glutamate was added to the cells at a concentration corresponding to EC 20  (typically around 80 μM) with on-line recording of fluorescence; in order to account for day-to-day variations in the responsiveness of cells, the EC 20  of glutamate was determined immediately ahead of each experiment by recording of a full dose-response curve of glutamate. 
         [0338]    Responses were measured as peak increase in fluorescence minus basal (i.e. fluorescence without addition of L-glutamate), normalized to the maximal stimulatory effect obtained with saturating concentrations of L-glutamate. Graphs were plotted with the % maximal stimulatory using XLfit, a curve fitting program that iteratively plots the data using Levenburg Marquardt algorithm. The single site competition analysis equation used was y=A+((B−A)/(1+((x/C)D))), where y is the % maximal stimulatory effect, A is the minimum y, B is the maximum y, C is the EC 50 , x is the log 10 of the concentration of the competing compound and D is the slope of the curve (the Hill Coefficient). From these curves the EC 50  (concentration at which half maximal stimulation was achieved), the Hill coefficient as well as the maximal response in % of the maximal stimulatory effect obtained with saturating concentrations of L-glutamate were calculated. 
         [0339]    Positive signals obtained during the pre-incubation with the PAM test compounds (i.e. before application of an EC 20  concentration of L-glutamate) were indicative of an agonistic activity, the absence of such signals were demonstrating the lack of agonistic activities. A depression of the signal observed after addition of the EC 20  concentration of L-glutamate was indicative of an inhibitory activity of the test compound. 
         [0340]    In the list of examples below are shown the corresponding results for compounds which all have 
         [0000]      EC 50 &lt;300 nM. 
         [0341]    The compounds of formula (I) and pharmaceutically acceptable salts thereof can be used as medicaments, e.g. in the form of pharmaceutical compositions. The pharmaceutical compositions can be administered orally, e.g. in the form of tablets, coated tablets, dragées, hard and soft gelatin capsules, solutions, emulsions or suspensions. However, the administration can also be effected rectally, e.g. in the form of suppositories, or parenterally, e.g. in the form of injectable solutions. 
         [0342]    The present invention also provides pharmaceutical compositions containing compounds of the invention, for example, compounds of formula I or pharmaceutically acceptable salts thereof and a pharmaceutically acceptable carrier. Such pharmaceutical compositions can be in the form of tablets, coated tablets, dragées, hard and soft gelatin capsules, solutions, emulsions or suspensions. The pharmaceutical compositions also can be in the form of suppositories or injectable solutions. 
         [0343]    The pharmaceutical compositions of the invention, in addition to one or more compounds of the invention, contain a pharmaceutically acceptable carrier. Suitable pharmaceutically acceptable carriers include pharmaceutically inert, inorganic or organic carriers. lactose, corn starch or derivatives thereof, talc, stearic acid or its salts and the like, for example, as such carriers for tablets, coated tablets, dragées and hard gelatin capsules. Suitable carriers for soft gelatin capsules are, for example, vegetable oils, waxes, fats, semi-solid and liquid polyols and the like; depending on the nature of the active substance no carriers are, however, usually required in the case of soft gelatin capsules. Suitable carriers for the production of solutions and syrups are, for example, water, polyols, sucrose, invert sugar, glucose and the like. Adjuvants, such as alcohols, polyols, glycerol, vegetable oils and the like, can be used for aqueous injection solutions of water-soluble salts of compounds of formula (I), but as a rule are not necessary. Suitable carriers for suppositories are, for example, natural or hardened oils, waxes, fats, semi-liquid or liquid polyols and the like. 
         [0344]    In addition, the pharmaceutical compositions can contain preservatives, solubilizers, stabilizers, wetting agents, emulsifiers, sweeteners, colorants, flavorants, salts for varying the osmotic pressure, buffers, masking agents or antioxidants. They can also contain still other therapeutically valuable substances. 
         [0345]    As mentioned earlier, medicaments containing a compound of formula (I) or pharmaceutically acceptable salts thereof and a therapeutically inert excipient are also an object of the present invention, as is a process for the production of such compositions which comprises bringing one or more compounds of formula I or pharmaceutically acceptable salts thereof and, if desired, one or more other therapeutically valuable substances into a galenical dosage form together with one or more therapeutically inert carriers. 
         [0346]    As further mentioned earlier, the use of the compounds of formula (I) for the preparation of pharmaceutical compositions useful in the prevention and/or the treatment of the above-recited diseases is also an aspect of the present invention. 
         [0347]    The dosage at which compounds of the invention can be administered can vary within wide limits and will, of course, be fitted to the individual requirements in each particular case. In general, the effective dosage for oral or parenteral administration is between 0.01-20 mg/kg/day, with a dosage of 0.1-10 mg/kg/day being preferred for all of the indications described. The daily dosage for an adult human being weighing 70 kg accordingly lies between 0.7-1400 mg per day, preferably between 7 and 700 mg per day. 
         [0000]    Preparation of pharmaceutical compositions comprising compounds of the invention:
 
Tablets of the following composition are produced in a conventional manner:
 
         [0000]    
       
         
               
               
               
             
               
               
               
             
           
               
                   
                   
               
               
                   
                   
                 mg/Tablet 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Active ingredient 
                 100 
               
               
                   
                 Powdered. lactose 
                 95 
               
               
                   
                 White corn starch 
                 35 
               
               
                   
                 Polyvinylpyrrolidone 
                 8 
               
               
                   
                 Na carboxymethylstarch 
                 10 
               
               
                   
                 Magnesium stearate 
                 2 
               
               
                   
                 Tablet weight 
                 250 
               
               
                   
                   
               
             
          
         
       
     
       LIST OF EXAMPLES 
       [0348]      
         [0000]    
       
         
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                   
                 EC 50  (nM) 
                 Eff. 
               
               
                 Ex. 
                 Structure 
                 Name 
                 mGlu5PAM 
                 (%) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-(3-Fluoro-5-  phenylethynyl-pyridin-  2-yl)-5,5-dimethyl- oxazolidin-2-one  
                 30 
                 68 
               
               
                   
               
               
                 2 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (5RS)-5- Methoxymethyl-3-(5- phenylethynyl-pyridin- 2-yl)-oxazolidin-2-one 
                 47 
                 34 
               
               
                   
               
               
                 3 
                                           
                            
 
                 (5R or 5S)-5- Methoxymethyl-3-(5- phenylethynyl-pyridin- 2-yl)-oxazolidin-2-one 
                 18 
                 46 
               
               
                   
               
               
                 4 
                                           
                            
 
                 (5S or 5R)-5- Methoxymethyl-3-(5- phenylethynyl-pyridin- 2-yl)-oxazolidin-2- 
                 278 
                 98 
               
               
                   
               
               
                 5 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-3-(5- phenylethynyl-pyridin- 2-yl)-oxazolidin-2-one 
                 7 
                 77 
               
               
                   
               
               
                 6 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(3-Fluoro- phenylethynyl)-pyridin- 2-yl]-5,5-dimethyl- oxazolidin-2-one 
                 9 
                 46 
               
               
                   
               
               
                 7 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-3-(5- pyridin-3-ylethynyl- pyridin-2-yl)- oxazolidin-2-one 
                 33 
                 39 
               
               
                   
               
               
                 8 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (5RS)-5-tert-Butyl-3- (5-phenylethynyl- pyridin-2-yl)- oxazolidin-2-one 
                 17 
                 62 
               
               
                   
               
               
                 9 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6-(5-Phenylethynyl- pyridin-2-yl)-4-oxa-6- aza-spiro[2.4]heptan-5- one  
                 15 
                 83 
               
               
                   
               
               
                 10 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 7-(5-Phenylethynyl- pyridin-2-yl)-5-oxa-7- aza-spiro[3.4]octan-6- one 
                 25 
                 109 
               
               
                   
               
               
                 11 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-(5-Phenylethynyl- pyridin-2-yl)-1-oxa-3- aza-spiro[4.4]nonan-2- one 
                 39 
                 52 
               
               
                   
               
               
                 12 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-(5-Phenylethynyl- pyridin-2-yl)-1-oxa-3- aza-spiro[4.5]decan-2- one 
                 67 
                 80 
               
               
                   
               
               
                 13 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-Dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-pyrrolidin-2-one 
                 37 
                 129 
               
               
                   
               
               
                 14 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3RS)-3-Hydroxy-4,4- dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-pyrrolidin-2-one 
                 388 
                 114 
               
               
                   
               
               
                 15 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-Dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-imidazolidin-2- one 
                 130 
                 101 
               
               
                   
               
               
                 16 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-imidazolidin-2- one 
                 35 
                 103 
               
               
                   
               
               
                 17 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-Ethyl-4,4-dimethyl- 1-(5-phenylethynyl- pyridin-2-yl)- imidazolidin-2-one 
                 66 
                 103 
               
               
                   
               
               
                 18 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-Isopropyl-4,4- dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-imidazolidin-2- one 
                 39 
                 133 
               
               
                   
               
               
                 19 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (5RS)-5-tert-Butyl-5- methyl-3-(5- phenylethynyl-pyridin- 2-yl)-oxazolidin-2-one  
                 27 
                 85 
               
               
                   
               
               
                 20 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-3-(5- phenylethynyl-pyridin- 2-yl)-[1,3]oxazinan-2- one  
                 27 
                 135 
               
               
                   
               
               
                 21 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-(3-Fluoro-5- phenylethynyl-pyridin- 2-yl)-4,4-dimethyl- pyrrolidin-2-one 
                 30 
                 128 
               
               
                   
               
               
                 22 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aRS,6aSR)-3-(5- Phenylethynyl-pyridin- 2-yl)-hexahydro- cyclopentaoxazol-2- one 
                 14 
                 74 
               
               
                   
               
               
                 23 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aRS,6aSR)-3-(5- Pyridin-3-ylethynyl- pyridin-2-yl)- hexahydro- cyclopentaoxazol-2- one 
                 12 
                 92 
               
               
                   
               
               
                 24 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aRS,6aSR)-3-[5-(5- Fluoro-pyridin-3- ylethynyl)-pyridin-2- yl]-hexahydro- cyclopentaoxazol-2- one 
                 35 
                 73 
               
               
                   
               
               
                 25 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-tetrahydro- pyrimidin-2-one 
                 69 
                 148 
               
               
                   
               
               
                 26 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1,5,5-Trimethyl-3-(5- phenylethynyl-pyridin- 2-yl)-tetrahydro- pyrimidin-2-one 
                 33 
                 131 
               
               
                   
               
               
                 27 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-4,5,5-Trimethyl- 3-(5-phenylethynyl- pyridin-2-yl)- oxazolidin-2-one 
                 15 
                 61 
               
               
                   
               
               
                 28 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4,5,5-Tetramethyl- 3-(5-phenylethynyl- pyridin-2-yl)- oxazolidin-2-one 
                 48 
                 31 
               
               
                   
               
               
                 29 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(5-Fluoro-pyridin-  3-ylethynyl)-pyridin-2-  yl]-5,5-dimethyl- oxazolidin-2-one  
                 15 
                 45 
               
               
                   
               
               
                 30 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-3-(5- pyrimidin-5- ylethynyl-pyridin-2- yl)-oxazolidin-2-one 
                 80 
                 43 
               
               
                   
               
               
                 31 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-3-[5-(1- methyl-1H-pyrazol-4- ylethynyl)-pyridin-2- yl]-oxazolidin-2-one 
                 26 
                 55 
               
               
                   
               
               
                 32 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(4-Fluoro- phenylethynyl)- pyridin-2-yl]-5,5- dimethyl-oxazolidin- 2-one 
                 19 
                 60 
               
               
                   
               
               
                 33 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(3,4-Difluoro- phenylethynyl)-pyridin- 2-yl]-5,5-dimethyl- oxazolidin-2-one 
                 32 
                 44 
               
               
                   
               
               
                 34 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(2,5-Difluoro- phenylethynyl)- pyridin-2-yl]- 5,5-dimethyl- oxazolidin-2-one 
                 11 
                 38 
               
               
                   
               
               
                 35 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(6-Fluoro-pyridin- 3-ylethynyl)-pyridin-2- yl]-5,5-dimethyl- oxazolidin-2-one 
                 54 
                 52 
               
               
                   
               
               
                 36 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6-(5-Pyridin-3- ylethynyl-pyridin-2- yl)-4-oxa-6-aza- spiro[2.4]heptan-5- one 
                 58 
                 80 
               
               
                   
               
               
                 37 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(5-Fluoro-pyridin- 3-ylethynyl)-pyridin-2- yl]-4,4-dimethyl- pyrrolidin-2-one 
                 22 
                 96 
               
               
                   
               
               
                 38 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-Dimethyl-1-(5- pyridin-3-ylethynyl- pyridin-2-yl)- pyrrolidin-2-one 
                 33 
                 147 
               
               
                   
               
               
                 39 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(5-Chloro-pyridin- 3-ylethynyl)-pyridin-2- yl]-4,4-dimethyl- pyrrolidin-2-one 
                 48 
                 98 
               
               
                   
               
               
                 40 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)-pyridin- 2- yl]-4,4-dimethyl- pyrrolidin-2-one 
                 15 
                 100 
               
               
                   
               
               
                 41 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-Dimethyl-1-(3- methyl-5- phenylethynyl-pyridin- 2-yl)-pyrrolidin-2-one 
                 58 
                 89 
               
               
                   
               
               
                 42 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-5′- phenylethynyl-3,4,5,6- tetrahydro- [1,2′]bipyridinyl-2-one 
                 16 
                 139 
               
               
                   
               
               
                 43 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(3-Fluoro- phenylethynyl)-5,5- dimethyl-3,4,5,6- tetrahydro- [1,2′]bipyridinyl-2-one 
                 12 
                 100 
               
               
                   
               
               
                 44 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-Methyl-3-(5- phenylethynyl-pyridin- 2-yl)-1,3-diaza- spiro[4.4]nonan-2-one 
                 29 
                 92 
               
               
                   
               
               
                 45 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-4-Cyclopentyl-3- methyl-1-(5- phenylethynyl-pyridin- 2-yl)-imidazolidin-2- one 
                 57 
                 97 
               
               
                   
               
               
                 46 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (1RS,5SR)-6-(5- Phenylethynyl-pyridin- 2-yl)-6-aza- bicyclo[3.2.0]heptan-7- one 
                 26 
                 27 
               
               
                   
               
               
                 47 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (6SR,7RS)-3-(5- Phenylethynyl-pyridin- 2-yl)-hexahydro- benzooxazol-2-one 
                 36 
                 109 
               
               
                   
               
               
                 48 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1-(5- pyridin-3-ylethynyl- pyridin-2-yl)- imidazolidin-2-one 
                 14 
                 89 
               
               
                   
               
               
                 49 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(5-Fluoro-pyridin- 3-ylethynyl)-pyridin-2- yl]-3,4,4-trimethyl- imidazolidin-2-one 
                 37 
                 91 
               
               
                   
               
               
                 50 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1-[5- (1-methyl-1H-pyrazol- 4-ylethynyl)-pyridin-2- yl]-imidazolidin-2-one 
                 27 
                 41 
               
               
                   
               
               
                 51 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(5-Chloro-pyridin- 3-ylethynyl)-pyridin-2- yl]-3,4,4-trimethyl- imidazolidin-2-one 
                 29 
                 45 
               
               
                   
               
               
                 52 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1-(5- pyridazin-4-ylethynyl- pyridin-2-yl)- imidazolidin-2-one 
                 34 
                 32 
               
               
                   
               
               
                 53 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)-pyridin- 2-yl]-3,4,4-trimethyl- imidazolidin-2-one 
                 29 
                 103 
               
               
                   
               
               
                 54 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Chloro- phenylethynyl)-pyridin- 2-yl]-3,4,4-trimethyl- imidazolidin-2-one 
                 32 
                 47 
               
               
                   
               
               
                 55 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1-(5- pyrimidin-5-ylethynyl- pyridin-2-yl)- imidazolidin-2-one  
                 54 
                 110 
               
               
                   
               
               
                 56 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1-(5- m-tolylethynyl-pyridin- 2-yl)-imidazolidin-2- one 
                 87 
                 56 
               
               
                   
               
               
                 57 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(4-Fluoro- phenylethynyl)-pyridin- 2-yl]-3,4,4-trimethyl- imidazolidin-2-one 
                 35 
                 78 
               
               
                   
               
               
                 58 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-2-(5-Phenylethynyl- pyridin-2-yl)-hexahydro- imidazo[1,5-a]pyridin-3- one 
                 33 
                 43 
               
               
                   
               
               
                 59 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 2-(5-Phenylethynyl- pyridin-2-yl)-2-aza- spiro[4.4]nonan-3-one 
                 16 
                 81 
               
               
                   
               
               
                 60 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-3-Methoxy-4,4- dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-pyrrolidin-2-one 
                 35 
                 89 
               
               
                   
               
               
                 61 
                                           
                            
 
                 (R or S)-3-Methoxy- 4,4-dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-pyrrolidin-2-one  
                 75 
                 70 
               
               
                   
               
               
                 62 
                                           
                            
 
                 (S or R)-3-Methoxy- 4,4-dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-pyrrolidin-2-one 
                 12 
                 86 
               
               
                   
               
               
                 63 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-1-[5-(5-Chloro- pyridin-3-ylethynyl)- pyridin-2-yl]-3- methoxy-4,4-dimethyl- pyrrolidin-2-one 
                 70 
                 99 
               
               
                   
               
               
                 64 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-3-Methoxy-4,4- dimethyl-1-(5-m- tolylethynyl-pyridin-2- yl)-pyrrolidin-2-one 
                 87 
                 56 
               
               
                   
               
               
                 65 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-1-[5-(3-Fluoro- phenylethynyl)-pyridin- 2-yl]-3-methoxy-4,4- dimethyl-pyrrolidin-2- one 
                 43 
                 91 
               
               
                   
               
               
                 66 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-1-[5-(4-Fluoro- phenylethynyl)-pyridin- 2-yl]-3-methoxy-4,4- dimethyl-pyrrolidin-2- one 
                 75 
                 87 
               
               
                   
               
               
                 67 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-tetrahydro- pyrimidin-2-one 
                 15 
                 81 
               
               
                   
               
               
                 68 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(2,5-Difluoro- phenylethynyl)-pyridin- 2-yl]-3,4,4-trimethyl- tetrahydro-pyrimidin-2- one  
                 41 
                 79 
               
               
                   
               
               
                 69 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(4-Fluoro- phenylethynyl)-pyridin- 2-yl]-3,4,4-trimethyl- tetrahydro-pyrimidin-2- one 
                 49 
                 107 
               
               
                   
               
               
                 70 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-2-(5-Pyridin-3- ylethynyl-pyridin-2-yl)- hexahydro- imidazo[1,5-a]pyridin- 3-one   
                 74 
                 51 
               
               
                   
               
               
                 71 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-2-[5-(3-Fluoro- phenylethynyl)-pyridin- 2-yl]-hexahydro- imidazo[1,5-a]pyridin- 3-one 
                 17 
                 41 
               
               
                   
               
               
                 72 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6,6-Dimethyl-3-(5- phenylethynyl-pyridin- 2-yl)-[1,3]oxazinan-2- one 
                 10 
                 86 
               
               
                   
               
               
                 73 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6,6-Dimethyl-3-(5- pyridin-3-ylethynyl- pyridin-2-yl)-  [1,3]oxazinan-2-one 
                 59 
                 98 
               
               
                   
               
               
                 74 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(5-Fluoro-pyridin- 3-ylethynyl)-pyridin-2- yl]-6,6-dimethyl- [1,3]oxazinan-2-one 
                 59 
                 108 
               
               
                   
               
               
                 75 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(5-Chloro-pyridin- 3-ylethynyl)-pyridin-2- yl]-6,6-dimethyl- [1,3]oxazinan-2-one  
                 27 
                 87 
               
               
                   
               
               
                 76 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(3-Fluoro- phenylethynyl)-pyridin- 2-yl]-6,6-dimethyl- [1,3]oxazinan-2-one 
                 13 
                 124 
               
               
                   
               
               
                 77 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(3-Chloro- phenylethynyl)-pyridin- 2-yl]-6,6-dimethyl- [1,3]oxazinan-2-one 
                 12 
                 72 
               
               
                   
               
               
                 78 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6,6-Dimethyl-3-(5-m- tolylethynyl-pyridin-2- yl)-[1,3]oxazinan-2-one 
                 24 
                 72 
               
               
                   
               
               
                 79 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(4-Fluoro- phenylethynyl)-pyridin- 2-yl]-6,6-dimethyl- [1,3]oxazinan-2-one 
                 22 
                 85 
               
               
                   
               
               
                 80 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(3,4-Difluoro- phenylethynyl)-pyridin- 2-yl]-6,6-dimethyl- [1,3]oxazinan-2-one 
                 37 
                 69 
               
               
                   
               
               
                 81 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-[5-(2,5-Difluoro- phenylethynyl)-pyridin- 2-yl]-6,6-dimethyl- [1,3]oxazinan-2-one  
                 12 
                 95 
               
               
                   
               
               
                 82 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6-(5-Phenylethynyl- pyridin-2-yl)-2-oxa-6- aza-spiro[3.4]octan-7- one 
                 57 
                 72 
               
               
                   
               
               
                 83 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-4-Cyclopropyl-3- methyl-1-(5- phenylethynyl-pyridin- 2-yl)-imidazolidin-2- one 
                 53 
                 86 
               
               
                   
               
               
                 84 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aSR,7aRS)- (3aRS,7RS)-1-Methyl- 3-(5-phenylethynyl- pyridin-2-yl)- octahydro- benzoimidazol-2-one 
                 11 
                 64 
               
               
                   
               
               
                 85 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aSR,7aRS)- (3aRS,7RS)-1-Methyl- 3-(5-pyridin-3- ylethynyl-pyridin-2-yl)- octahydro- benzoimidazol-2-one 
                 27 
                 49 
               
               
                   
               
               
                 86 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aSR,7aRS)- (3aRS,7RS)-1-[5-(5- Fluoro-pyridin-3- ylethynyl)-pyridin-2- yl]-3-methyl-octahydro- benzoimidazol-2-one 
                 32 
                 52 
               
               
                   
               
               
                 87 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-Dimethyl-5′- phenylethynyl-3,4,5,6- tetrahydro- [1,2′]bipyridinyl-2-one 
                 12 
                 89 
               
               
                   
               
               
                 88 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(3-Fluoro- phenylethynyl)-4,4- dimethyl-3,4,5,6- tetrahydro- [1,2′]bipyridinyl-2-one 
                 19 
                 110 
               
               
                   
               
               
                 89 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(3-Chloro- phenylethynyl)-4,4- dimethyl-3,4,5,6- tetrahydro- [1,2′]bipyridinyl-2-one  
                 25 
                 78 
               
               
                   
               
               
                 90 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(5-Chloro-pyridin-3- ylethynyl)-4,4-dimethyl- 3,4,5,6-tetrahydro- [1,2′]bipyridinyl-2-one 
                 66 
                 90 
               
               
                   
               
               
                 91 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(4-Fluoro- phenylethynyl)-4,4- dimethyl-3,4,5,6- tetrahydro- [1,2′]bipyridinyl-2-one 
                 67 
                 89 
               
               
                   
               
               
                 92 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(2,5-Difluoro- phenylethynyl)-4,4- dimethyl-3,4,5,6- tetrahydro- [1,2′]bipyridinyl-2-one 
                 32 
                 84 
               
               
                   
               
               
                 93 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 7,7-Dimethyl-3-(5- phenylethynyl-pyridin- 2-yl)-[1,3]oxazepan-2- one 
                 36 
                 104 
               
               
                   
               
               
                 94 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aSR,7aRS)- (3aRS,7RS)-1-(5- Phenylethynyl-pyridin- 2-yl)-hexahydro- pyrano[4,3-d]oxazol-2- one 
                 60 
                 84 
               
               
                   
               
               
                 95 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-5-Hydroxy-6,6- dimethyl-3-(5- phenylethynyl-pyridin- 2-yl)-[1,3]oxazinan-2- one 
                 47 
                 118 
               
               
                   
               
               
                 96 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4-Methyl-6-(5- phenylethynyl-pyridin- 2-yl)-4,6-diaza- spiro[2.4]heptan-5-one 
                 35 
                 98 
               
               
                   
               
               
                 97 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,3-Dimethyl-1-(5- phenylethynyl-pyridin- 2-yl)-azetidin-2-one 
                 36 
                 71 
               
               
                   
               
               
                 98 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (1RS,5SR)-6-(5- Pyridin-3-ylethynyl- pyridin-2-yl)-6-aza- bicyclo[3.2.0]heptan- 7-one 
                 39 
                 73 
               
               
                   
               
               
                 99 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aSR,7aRS)- (3aRS,7RS)-1-Ethyl- 3-(5-phenylethynyl- pyridin-2-yl)- octahydro- benzoimidazol-2-one 
                 18 
                 90 
               
               
                   
               
               
                 100 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aSR,7aRS)-  (3aRS,7RS)-1-Ethyl-3- (5-pyridin-3-ylethynyl- pyridin-2-yl)-octahydro- benzoimidazol-2-one 
                 69 
                 64 
               
               
                   
               
               
                 101 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aSR,7aRS)- (3aRS,7RS)-1- Isopropyl-3-(5- phenylethynyl-pyridin- 2-yl)-octahydro- benzoimidazol-2-one 
                 39 
                 77 
               
               
                   
               
               
                 102 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (4aRS,7aSR)-3-(5- Phenylethynyl-pyridin- 2-yl)-hexahydro-cyclo- penta[e][1,3]oxazin- 2-one 
                 43 
                 115 
               
               
                   
               
               
                 103 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (4aRS,7aRS)-3-(5- Phenylethynyl-pyridin- 2-yl)-hexahydro- cyclo- penta[e] [1,3]oxazin- 2-one 
                 27 
                 123 
               
               
                   
               
               
                 104 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-5,6,6-Trimethyl-3- (5-phenylethynyl- pyridin-2-yl)- [1,3]oxazinan-2-one 
                 42 
                 109 
               
               
                   
               
               
                 105 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-6- Methoxymethyl-3-(5- phenylethynyl-pyridin- 2-yl)-[1,3]oxazinan-2- one 
                 68 
                 51 
               
               
                   
               
               
                 106 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aRS,6aSR)-1-Methyl- 3-(5-(phenylethynyl) pyridin-2-yl)hexa- hydrocyclopenta[d] imidazol-2(1H)-one 
                 30 
                 42 
               
               
                   
               
               
                 107 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-4-tert-Butyl-3- methyl-1-(5- phenylethynyl-pyridin- 2-yl)-imidazolidin-2- one 
                 59 
                 106 
               
               
                   
               
               
                 108 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)-3- methyl-pyridin-2-yl]- 3,4,4-trimethyl- imidazolidin-2-one 
                 102 
                 115 
               
               
                   
               
               
                 109 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aRS, 6aSR)-1-[5-(3- Fluoro-phenylethynyl)- pyridin-2-yl]-3-methyl- hexahydro-cyclopenta- imidazol-2-one 
                 18 
                 37 
               
               
                   
               
               
                 110 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[3-Fluoro-5-(4- fluoro-phenylethynyl)- pyridin-2-yl]-3,4,4- trimethyl-imidazolidin- 2-one 
                 96 
                 117 
               
               
                   
               
               
                 111 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[3-Fluoro-5-(3- fluoro-phenylethynyl)- pyridin-2-yl]-3,4,4- trimethyl-imidazolidin- 2-one 
                 32 
                 107 
               
               
                   
               
               
                 112 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6-[5-(4-Fluoro- phenylethynyl)-pyridin- 2-yl]-4-methyl-4,6- diaza-spiro[2.4]heptan- 5-one 
                 80 
                 89 
               
               
                   
               
               
                 113 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6-[5-(3-Fluoro- phenylethynyl)-pyridin- 2-yl]-4-methyl-4,6- diaza-spiro[2.4]heptan- 5-one 
                 51 
                 75 
               
               
                   
               
               
                 114 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-5-Methoxy-6,6- dimethyl-3-(5- phenylethynyl-pyridin- 2-yl)-[1,3]oxazinan- 2-one 
                 22 
                 57 
               
               
                   
               
               
                 115 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-Dimethyl-1-(5- phenylethynyl- pyrimidin-2-yl)- pyrrolidin-2-one 
                 13 
                 109 
               
               
                   
               
               
                 116 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-Dimethyl-1-(5- phenylethynyl- pyrimidin-2-yl)- piperidin-2-one 
                 41 
                 101 
               
               
                   
               
               
                 117 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 2-(5-Phenylethynyl- pyrimidin-2-yl)-2-aza- spiro[4.4]nonan-3-one 
                 44 
                 84 
               
               
                   
               
               
                 118 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-4,4- dimethyl-pyrrolidin-2- one 
                 13 
                 78 
               
               
                   
               
               
                 119 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Chloro- phenylethynyl)- pyrimidin-2-yl]-4,4- dimethyl-pyrrolidin-2- one 
                 11 
                 26 
               
               
                   
               
               
                 120 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(4-Fluoro- phenylethynyl)- pyrimidin-2-yl]-4,4- dimethyl-pyrrolidin-2- one 
                 92 
                 81 
               
               
                   
               
               
                 121 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(2,5-Difluoro- phenylethynyl)- pyrimidin-2-yl]-4,4- dimethyl-pyrrolidin-2- one 
                 41 
                 70 
               
               
                   
               
               
                 122 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-1- (5-phenylethynyl- pyrimidin-2-yl)- imidazolidin-2-one 
                 11 
                 36 
               
               
                   
               
               
                 123 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3,4,4- trimethyl-imidazolidin- 2-one 
                 18 
                 30 
               
               
                   
               
               
                 124 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(2,5-Difluoro- phenylethynyl)- pyrimidin-2-yl]-3,4,4- trimethyl-imidazolidin- 2-one 
                 7 
                 43 
               
               
                   
               
               
                 125 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(4-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3,4,4- trimethyl-imidazolidin- 2-one 
                 13 
                 44 
               
               
                   
               
               
                 126 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3,4-Difluoro- phenylethynyl)- pyrimidin-2-yl]-3,4,4- trimethyl-imidazolidin- 2-one 
                 23 
                 36 
               
               
                   
               
               
                 127 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-3-Methoxy-4,4- dimethyl-1-(5- phenylethynyl- pyrimidin-2-yl)- pyrrolidin-2-one 
                 29 
                 94 
               
               
                   
               
               
                 128 
                                           
                            
 
                 (R or S)-3-Methoxy- 4,4-dimethyl-1-(5- phenylethynyl- pyrimidin-2-yl)- pyrrolidin-2-one  
                 46 
                 54 
               
               
                   
               
               
                 129 
                                           
                            
 
                 (S or R)-3-Methoxy- 4,4-dimethyl-1-(5- phenylethynyl- pyrimidin-2-yl)- pyrrolidin-2-one 
                 18 
                 90 
               
               
                   
               
               
                 130 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3- methoxy-4,4-dimethyl- pyrrolidin-2-one 
                 41 
                 74 
               
               
                   
               
               
                 131 
                                           
                            
 
                 (R or S)-1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3- methoxy-4,4-dimethyl- pyrrolidin-2-one 
                 35 
                 48 
               
               
                   
               
               
                 132 
                                           
                            
 
                 (S or R)-1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3- methoxy-4,4-dimethyl- pyrrolidin-2-one 
                 21 
                 69 
               
               
                   
               
               
                 133 
                                           
                            
 
                 (R or S)-1-[5-(2,5- Difluoro- phenylethynyl)- pyrimidin-2-yl]-3- methoxy-4,4-dimethyl- pyrrolidin-2-one 
                 57 
                 49 
               
               
                   
               
               
                 134 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-Dimethyl-1-(5- phenylethynyl- pyrimidin-2-yl)- piperidin-2-one 
                 42 
                 90 
               
               
                   
               
               
                 135 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-4,4- dimethyl-piperidin-2- one 
                 35 
                 47 
               
               
                   
               
               
                 136 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(2,5-Difluoro- phenylethynyl)- pyrimidin-2-yl]-4,4- dimethyl-piperidin-2- one 
                 31 
                 49 
               
               
                   
               
               
                 137 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-Trimethyl-5′- phenylethynyl-3,4,5,6- tetrahydro- [1,2′]bipyrimidinyl-2- one 
                 66 
                 74 
               
               
                   
               
               
                 138 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(3-Fluoro- phenylethynyl)-3,4,4- trimethyl-3,4,5,6- tetrahydro- [1,2&#39;]bipyrimidinyl-2- one 
                 60 
                 67 
               
               
                   
               
               
                 139 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5′-(2,5-Difluoro- phenylethynyl)-3,4,4- trimethyl-3,4,5,6- tetrahydro- [1,2′]bipyrimidinyl-2- one 
                 57 
                 54 
               
               
                   
               
               
                 140 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3-Isopropyl-4,4- dimethyl-1-(5- phenylethynyl- pyrimidin-2-yl)- imidazolidin-2-one 
                 28 
                 58 
               
               
                   
               
               
                 141 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3- isopropyl-4,4-dimethyl- imidazolidin-2-one 
                 28 
                 39 
               
               
                   
               
               
                 142 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(4-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3- isopropyl-4,4-dimethyl- imidazolidin-2-one 
                 78 
                 74 
               
               
                   
               
               
                 143 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(4-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3-ethyl- 4,4-dimethyl- imidazolidin-2-one 
                 47 
                 68 
               
               
                   
               
               
                 144 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-3- ethyl-4,4-dimethyl- imidazolidin-2-one 
                 31 
                 58 
               
               
                   
               
               
                 145 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-5,6,6-Trimethyl- 3-(5-phenylethynyl- pyrimidin-2-yl)- [1,3]oxazinan-2-one 
                 38 
                 93 
               
               
                   
               
               
                 146 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-3-[5-(2,5-Difluoro- phenylethynyl)- pyrimidin-2-yl]-5,6,6- trimethyl- [1,3]oxazinan-2-one 
                 69 
                 64 
               
               
                   
               
               
                 147 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4-Methyl-6-(5- phenylethynyl- pyrimidin-2-yl)-4,6- diaza-spiro[2.4]heptan- 5-one 
                 25 
                 36 
               
               
                   
               
               
                 148 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-3-[5-(3-Fluoro- phenylethynyl)- pyrimidin-2-yl]-5,6,6- trimethyl- [1,3]oxazinan-2-one 
                 39 
                 75 
               
               
                   
               
               
                 149 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-3-[5-(4-Fluoro- phenylethynyl)- pyrimidin-2-yl]-5,6,6- trimethyl- [1,3]oxazinan-2-one 
                 114 
                 78 
               
               
                   
               
               
                 150 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-dimethyl-1-(6- (phenylethynyl) pyridazin-3-yl) pyrrolidin-2-one 
                 21 
                 113 
               
               
                   
               
               
                 151 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-dimethyl-1-(6- (phenylethynyl)pyridazin- 3-yl)piperidin-2-one 
                 19 
                 130 
               
               
                   
               
               
                 152 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 5,5-dimethyl-3-(6- (phenylethynyl)pyridazin- 3-yl)oxazolidin-2-one 
                 15 
                 112 
               
               
                   
               
               
                 153 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6,6-dimethyl-3-(6- (phenylethynyl)pyridazin- 3-yl)-1,3-oxazinan-2- one 
                 14 
                 86 
               
               
                   
               
               
                 154 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-trimethyl-1-(6- (m- tolylethynyl)pyridazin- 3-yl)imidazolidin-2-one 
                 61 
                 108 
               
               
                   
               
               
                 155 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-(6-((3- chlorophenyl)ethynyl)  pyridazin-3-yl)-3,4,4- trimethylimidazolidin- 2-one 
                 73 
                 95 
               
               
                   
               
               
                 156 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-trimethyl-1-(5- (phenylethynyl)pyrazin- 2-yl)imidazolidin-2-one  
                 24 
                 58 
               
               
                   
               
               
                 157 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-trimethyl-1-(5- (pyridin-3- ylethynyl)pyrazin-2- yl)imidazolidin-2-one 
                 206 
                 34 
               
               
                   
               
               
                 158 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-(5-((3- fluorophenyl)ethynyl) pyrazin-2-yl)-3,4,4- trimethylimidazolidin- 2-one 
                 46 
                 36 
               
               
                   
               
               
                 159 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-[5-(4-Fluoro- phenylethynyl)-pyrazin- 2-yl]-3,4,4-trimethyl- imidazolidin-2-one 
                 49 
                 49 
               
               
                   
               
               
                 160 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-(5-((3- fluorophenyl)ethynyl) pyrazin-2-yl)-4,4- dimethylpyrrolidin-2- one 
                 29 
                 39 
               
               
                   
               
               
                 161 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-(5-((3- fluorophenyl)ethynyl) pyrazin-2-yl)-4,4- dimethylpiperidin-2-one 
                 29 
                 68 
               
               
                   
               
               
                 162 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-dimethyl-1-(5- (pyridin-3- ylethynyl)pyrazin-2- yl)piperidin-2-one 
                 681 
                 76 
               
               
                   
               
               
                 163 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-dimethyl-1-(5- (phenylethynyl)pyrazin- 2-yl)piperidin-2-one 
                 69 
                 74 
               
               
                   
               
               
                 164 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 4,4-dimethyl-1-(5- (phenylethynyl)pyrazin- 2-yl)tetrahydro- pyrimidin-2(1H)-one 
                 329 
                 89 
               
               
                   
               
               
                 165 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 3,4,4-trimethyl-1-(5- (phenylethynyl)pyrazin- 2-yl)tetrahydro- pyrimidin-2(1H)-one 
                 36 
                 55 
               
               
                   
               
               
                 166 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-(5-((3- fluorophenyl)ethynyl) pyrazin-2-yl)-4,4- dimethyltetrahydro- pyrimidin-2(1H)-one 
                 140 
                 56 
               
               
                   
               
               
                 167 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1-(5-((3- fluorophenyl)ethynyl) pyrazin-2-yl)-3,4,4- trimethyltetrahydro- pyrimidin-2(1H)-one 
                 26 
                 54 
               
               
                   
               
               
                 168 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6,6-dimethyl-3-(5- (phenylethynyl)pyrazin- 2-yl)-1,3-oxazinan-2- one 
                 15 
                 41 
               
               
                   
               
               
                 169 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-3-[5-(3-Fluoro- phenylethynyl)-pyridin- 2-yl]-5-methoxy-6,6- dimethyl- [1,3]oxazinan-2-one 
                 13 
                 52 
               
               
                   
               
               
                 170 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aRS,6aSR)-1-Methyl- 3-(6-phenylethynyl- pyridazin-3-yl)- hexahydro- cyclopentaimidazol-2- one 
                 13 
                 105 
               
               
                   
               
               
                 171 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (RS)-6-Methyl-4-(5- phenylethynyl-pyridin- 2-yl)-morpholin-3-one 
                 88 
                 73 
               
               
                   
               
               
                 172 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 6,6-Dimethyl-4-(5- phenylethynyl-pyridin- 2-yl)-morpholin-3-one 
                 29 
                 82 
               
               
                   
               
               
                 173 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 1,1-Dioxo-4-(5- phenylethynyl-pyridin- 2-yl)-thiomorpholin-3- one 
                 29 
                 82 
               
               
                   
               
               
                 174 
                 
                   
                             
                     
                         
                         
                     
                   
                 
                 (3aRS,6aSR)-1-[6-(3- Fluoro-phenylethynyl)- pyridazin-3-yl]-3- methyl-hexahydro- cyclopentaimidazol-2- one 
                 12 
                 56 
               
               
                   
               
             
          
         
       
     
       EXPERIMENTAL SECTION 
     Example 1 
     3-(3-Fluoro-5-phenylethynyl-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one 
       [0349]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(3-Fluoro-5-iodo-pyridin-2-ylamino)-2-methyl-propan-2-ol 
       [0350]    
       
                 
         
             
             
         
       
     
         [0351]    2,3-Difluoro-5-iodopyridine (500 mg, 2.07 mmol) was dissolved in NMP (500 μl) and pyridine (201 μl, 2.49 mmol, 1.2 equiv.) and 1-amino-2-methylpropan-2-ol (555 mg, 6.22 mmol, 3 equiv.) were added at room temperature. The mixture was stirred for 16 hours at 100° C. The reaction mixture was cooled and extracted with saturated NaHCO 3  solution and two times with a small volume of dichloromethane. The crude product was purified by flash chromatography by directly loading the dichloromethane layers onto a silica gel column and eluting with an ethyl acetate:heptane gradient 0:100 to 100:0. The desired 1-(3-fluoro-5-iodopyridin-2-ylamino)-2-methylpropan-2-ol (590 mg, 1.9 mmol, 91.7% yield) was obtained as a colorless oil, MS: m/e=311.0 (M+H + ). 
       Step 2: 3-(3-Fluoro-5-iodopyridin-2-yl)-5,5-dimethyloxazolidin-2-one 
       [0352]    
       
                 
         
             
             
         
       
     
         [0353]    (580 mg, 1.87 mmol) 1-(3-Fluoro-5-iodopyridin-2-ylamino)-2-methylpropan-2-ol (Example 1, step 1) was dissolved in dichloromethane (10 ml) and pyridine (300 μl, 3.74 mmol, 2 equiv.) was added at room temperature. The mixture was cooled to 0-5° C. and phosgene (20% in toluene) (1.19 ml, 2.24 mmol, 1.2 equiv.) was added dropwise over a period of 15 min at 0-5° C. The mixture was stirred for 1 hour at 0-5° C. The reaction mixture was extracted with saturated NaHCO 3  solution and two times with a small volume of dichloromethane. The crude product was purified by flash chromatography by directly loading the dichloromethane layers onto a silica gel column and eluting with a heptane:ethyl acetate gradient 100:0 to 50:50. The desired 3-(3-fluoro-5-iodopyridin-2-yl)-5,5-dimethyloxazolidin-2-one (500 mg, 1.49 mmol, 79.5% yield) was obtained as a white solid, MS: m/e=337.0 (M+H + ). 
       Step 3: 3-(3-Fluoro-5-phenylethynyl-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one 
       [0354]    
       
                 
         
             
             
         
       
     
         [0355]    Bis-(triphenylphosphine)-palladium(II)dichloride (12.5 mg, 17.9 μmol, 0.05 equiv.) was dissolved in 1 ml DMF. (120 mg, 357 μmol) 3-(3-Fluoro-5-iodopyridin-2-yl)-5,5-dimethyloxazolidin-2-one (Example 1, step 2) and phenylacetylene (72.9 mg, 78.4 μl, 714 μmol, 2 equiv.) were added at room temperature. Triethylamine (108 mg, 149 μl, 1.07 mmol, 3 equiv.), triphenylphosphine (2.81 mg, 10.7 μmol, 0.03 equiv.) and copper(I)iodide (2.04 mg, 10.7 μmol, 0.03 equiv.) were added and the mixture was stirred for 3 hours at 70° C. The reaction mixture was cooled and extracted with saturated NaHCO 3  solution and two times with a small volume of dichloromethane. The crude product was purified by flash chromatography by directly loading the dichloromethane layers onto a silica gel column and eluting with an ethyl acetate:heptane gradient 0:100 to 40:60. The desired 3-(3-fluoro-5-(phenylethynyl)pyridin-2-yl)-5,5-dimethyloxazolidin-2-one (96 mg, 309 μmol, 86.6% yield) was obtained as a yellow solid, MS: m/e=311.2 (M+H + ). 
       Example 2 
     (5RS)-5-Methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0356]    
       
                 
         
             
             
         
       
     
         [0357]    The title compound, a light brown solid, MS: m/e=309.1 (M+H + ), was prepared using a procedure similar to that described in Example 1, step 3 from 3-(5-bromo-pyridin-2-yl)-5-methoxymethyl-oxazolidin-2-one (CAS 170011-45-7) and phenylacetylene. 
       Example 3 
     (5R or 5S)-5-Methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0358]    
       
                 
         
             
             
         
       
     
         [0359]    The title compound, a white solid, MS: m/e=309.1 (M+H + ), was prepared by separation of (5RS)-5-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 2) using a chiral column (chiralpak AD with heptane:isopropanol 80:20 as solvent). 
       Example 4 
     (5S or 5R)-5-Methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0360]    
       
                 
         
             
             
         
       
     
         [0361]    The title compound, a white solid, MS: m/e=309.1 (M+H + ), was prepared by separation of (5RS)-5-methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 2) using a chiral column (chiralpak AD with heptane:isopropanol 80:20 as solvent). 
       Example 5 
     5,5-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0362]    
       
                 
         
             
             
         
       
     
       Step 1: 3-(5-Iodo-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one 
       [0363]    
       
                 
         
             
             
         
       
     
         [0364]    The title compound was obtained as a white solid, MS: m/e=292.9 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and 1-amino-2-methylpropan-2-ol. 
       Step 2: 5,5-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0365]    
       
                 
         
             
             
         
       
     
         [0366]    The title compound was obtained as a white solid, MS: m/e=293.0 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one (Example 5, step 1) and phenylacetylene. 
       Example 6 
     3-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one 
       [0367]    
       
                 
         
             
             
         
       
     
         [0368]    The title compound was obtained as a white solid, MS: m/e=311.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one (Example 5, step 1) and 3-fluorophenylacetylene. 
       Example 7 
     5,5-Dimethyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0369]    
       
                 
         
             
             
         
       
     
         [0370]    The title compound was obtained as a white solid, MS: m/e=294.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one (Example 5, step 1) and 3-ethynyl-pyridine. 
       Example 8 
     (5RS)-5-tert-Butyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0371]    
       
                 
         
             
             
         
       
     
       Step 1: (5RS)-5-tert-Butyl-3-(5-iodo-pyridin-2-yl)-oxazolidin-2-one 
       [0372]    
       
                 
         
             
             
         
       
     
         [0373]    The title compound was obtained as a white solid, MS: m/e=346.9 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and (rac)-1-amino-3,3-dimethylbutan-2-ol hydrochloride. 
       Step 2: (5RS)-5-tert-Butyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0374]    
       
                 
         
             
             
         
       
     
         [0375]    The title compound was obtained as a white solid, MS: m/e=321.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (5RS)-5-tert-butyl-3-(5-iodo-pyridin-2-yl)-oxazolidin-2-one (Example 8, step 1) and phenylacetylene. 
       Example 9 
     6-(5-Phenylethynyl-pyridin-2-yl)-4-oxa-6-aza-spiro[2.4]heptan-5-one 
       [0376]    
       
                 
         
             
             
         
       
     
         [0377]    The title compound was obtained as a colourless solid, MS: m/e=291.2 (M+H + ), using procedures similar to those described in Example 1 starting from 2-fluoro-5-bromopyridine, 1-aminomethyl-cyclopropanol ( Russian J. Org. Chem.  2001, 37, 1238) and phenylacetylene. 
       Example 10 
     7-(5-Phenylethynyl-pyridin-2-yl)-5-oxa-7-aza-spiro[3.4]octan-6-one 
       [0378]    
       
                 
         
             
             
         
       
     
         [0379]    The title compound was obtained as a light yellow solid, MS: m/e=305.2 (M+H + ), using procedures similar to those described in Example 1 starting from 2-fluoro-5-bromopyridine, 1-aminomethyl-cyclobutanol (WO2006/29115 A2) and phenylacetylene. 
       Example 11 
     3-(5-Phenylethynyl-pyridin-2-yl)-1-oxa-3-aza-spiro[4.4]nonan-2-one 
       [0380]    
       
                 
         
             
             
         
       
     
         [0381]    The title compound was obtained as a light yellow solid, MS: m/e=319.2 (M+H + ), using procedures similar to those described in Example 1 starting from 2-fluoro-5-bromopyridine, 1-aminomethyl-cyclopentanol and phenylacetylene. 
       Example 12 
     3-(5-Phenylethynyl-pyridin-2-yl)-1-oxa-3-aza-spiro[4.5]decan-2-one 
       [0382]    
       
                 
         
             
             
         
       
     
         [0383]    The title compound was obtained as a light yellow solid, MS: m/e=333.2 (M+H + ), using procedures similar to those described in Example 1 starting from 2-fluoro-6-bromopyridine, 1-aminomethyl-cyclohexanol and phenylacetylene. 
       Example 13 
     4,4-Dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0384]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Iodo-pyridin-2-yl)-3,3-dimethyl-pyrrolidine-2,5-dione 
       [0385]    
       
                 
         
             
             
         
       
     
         [0386]    5-iodopyridin-2-amine (1 g, 4.55 mmol) was dissolved in DMF (5 ml) and 3,3-dimethyldihydrofuran-2,5-dione (1.28 g, 10.0 mmol, 2.2 equiv.) was added at room temperature. The mixture was stirred for 3 hr at 150° C. The reaction mixture was evaporated to dryness and loaded directly to a silica gel column. The crude material was purified by flash chromatography on silica gel (20 gr, ethyl acetate/heptane gradient, 0:100 to 100:0). The desired 1-(5-iodopyridin-2-yl)-3,3-dimethylpyrrolidine-2,5-dione (1.3 g, 3.94 mmol, 86.6% yield) was obtained as a yellow solid, MS: m/e=331.0 (M+H + ). 
       Step 2: (5RS)-5-Hydroxy-1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one 
       [0387]    
       
                 
         
             
             
         
       
     
         [0388]    (800 mg, 2.42 mmol) 1-(5-Iodopyridin-2-yl)-3,3-dimethylpyrrolidine-2,5-dione (Example 13, step 1) was dissolved in THF (6 ml) and MeOH (2 ml) and the solution was cooled to 0-5° C. NaBH 4  (101 mg, 2.67 mmol, 1.1 equiv.) was added at 0-5° C. and the mixture was stirred for 1 hr at 0-5° C. The reaction mixture was extracted with sat. NaHCO 3  solution and two times with a small volume of dichloromethane. The crude product was purified by flash chromatography by directly loading the dichloromethane layers onto a amino-silica gel column and eluting with a ethyl acetate/heptane gradient, 0:100 to 100:0. The desired (5-RS)-5-hydroxy-1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one (370 mg, 46% yield) was obtained as a white solid, MS: m/e=333.0 (M+H + ). 
       Step 3: 1-(5-Iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one 
       [0389]    
       
                 
         
             
             
         
       
     
         [0390]    (275 mg, 828 μmol) (5RS)-5-Hydroxy-1-(5-iodopyridin-2-yl)-4,4-dimethylpyrrolidin-2-one (Example 13, step 2) was dissolved in CH 2 Cl 2  (2 ml) and trifluoroacetic anhydride (140 μl, 994 μmol, 1.2 equiv.) was added at room temperature. The mixture was stirred for 1 hr at 20-25° C. The solution was evaporated to dryness and the residue was dissolved in trifluoroacetic acid (957 μl, 12.4 mmol, 15 equiv.) and triethylsilane (159 μl, 994 μmol, 1.2 equiv.) was added at room temperature. The mixture was stirred 1 h at room temperature. The reaction mixture was evaporated and extracted with sat. NaHCO 3  solution and two times with a small volume of dichloromethane. The crude product was purified by flash chromatography by directly loading the dichloromethane layers onto a silica gel column (20 gr, ethyl acetate/heptane gradient, 0:100 to 100:0). The desired 1-(5-iodopyridin-2-yl)-4,4-dimethylpyrrolidin-2-one (209 mg, 80% yield) was obtained as a white solid, MS: m/e=317.0 (M+H + ). 
       Step 4: 4,4-Dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0391]    
       
                 
         
             
             
         
       
     
         [0392]    The title compound was obtained as a yellow oil, MS: m/e=291.1 (M+H + ), using chemistry that is described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one (Example 13, step 3) and phenylacetylene. 
       Example 14 
     (3RS)-3-Hydroxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0393]    
       
                 
         
             
             
         
       
     
       Step 1: (4RS)-4-Hydroxy-3,3-dimethyl-dihydro-furan-2,5-dione 
       [0394]    
       
                 
         
             
             
         
       
     
         [0395]    (3RS)-3-Hydroxy-2,2-dimethyl-succinic acid [Tetrahedron Letters (2002), 43(52), 9513-9515] (120 mg, 0.74 mmol) was suspended in CH 2 Cl 2  (2 ml) and cooled to 0-5° C. Trifluoroacetic anhydride (260 μl, 1.85 mmol) was added and the reaction mixture stirred for 2 hours at room temperature. The reaction mixture was evaporated to dryness and used without any further purification in the next step. 
       Step 2: (4RS)-4-Hydroxy-1-(5-iodo-pyridin-2-yl)-3,3-dimethyl-pyrrolidine-2,5-dione 
       [0396]    
       
                 
         
             
             
         
       
     
         [0397]    The title compound was obtained as a light yellow solid, MS: m/e=346.8 (M+H + ), using chemistry similar to that described in Example 12, step 1 from 5-iodopyridin-2-amine and (4RS)-4-hydroxy-3,3-dimethyl-dihydro-furan-2,5-dione (Example 14, step 1). 
       Step 3: (4RS)-4-(tert-Butyl-diphenyl-silanyloxy)-1-(5-iodo-pyridin-2-yl)-3,3-dimethyl-pyrrolidine-2,5-dione 
       [0398]    
       
                 
         
             
             
         
       
     
         [0399]    (2.4 g, 3.47 mmol, 50%) (4RS)-4-Hydroxy-1-(5-iodo-pyridin-2-yl)-3,3-dimethyl-pyrrolidine-2,5-dione (Example 14, step 2) was dissolved in dichloromethane (20 ml). Imidazole (520 mg, 7.63 mmol) and tert-butyldiphenylchlorosilane (1.0 g, 3.64 mmol) were added at room temperature and the mixture was stirred for 3 hours at room temperature. Sat. NaHCO 3  solution was added and the mixture was extracted with dichloromethane. The organic extracts were dried with sodium sulfate, filtered and evaporated. The crude product was purified by flash chromatography on silica gel (ethyl acetate/heptane gradient 0:100 to 30:70). The desired compound was obtained as a white solid (1.5 g, 74% yield), MS: m/e=585.1 (M+H + ). 
       Step 4: (3RS,5RS)-3-(tert-Butyl-diphenyl-silanyloxy)-5-hydroxy-1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one 
       [0400]    
       
                 
         
             
             
         
       
     
         [0401]    The title compound was obtained as a light yellow solid, MS: m/e=587.0 (M+H + ), using chemistry similar to that described in Example 12, step 2 from (4RS)-4-(tert-butyl-diphenyl-silanyloxy)-1-(5-iodo-pyridin-2-yl)-3,3-dimethyl-pyrrolidine-2,5-dione (Example 14, step 3). 
       Step 5: (3RS)-3-(tert-Butyl-diphenyl-silanyloxy)-1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one 
       [0402]    
       
                 
         
             
             
         
       
     
         [0403]    The title compound was obtained as a colorless oil, MS: m/e=571.1 (M+H + ), using chemistry similar to that described in Example 12, step 3 from (3RS,5RS)-3-(tert-butyl-diphenyl-silanyloxy)-5-hydroxy-1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one (Example 14, step 4). 
       Step 6: (3RS)-3-(tert-Butyl-diphenyl-silanyloxy)-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0404]    
       
                 
         
             
             
         
       
     
         [0405]    The title compound was obtained as a brown oil, MS: m/e=545.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3RS)-3-(tert-butyl-diphenyl-silanyloxy)-1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one (Example 14, step 5) and phenylacetylene. 
       Step 7: (3RS)-3-Hydroxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0406]    
       
                 
         
             
             
         
       
     
         [0407]    (100 mg, 0.18 mmol) (3RS)-3-(tert-Butyl-diphenyl-silanyloxy)-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 14, step 6) was dissolved in THF (1 ml) and TBAF (1M in THF) (184 μl, 0.184) was added drop wise at room temperature. The mixture was stirred for 1 hr at 60° C. The reaction mixture was extracted with sat. NaHCO 3 -solution and two times EtOAc. The organic layers were extracted with water, dried over Na 2 SO 4 , filtered and evaporated to dryness. The crude material was purified by flash chromatography on silica gel (20 gr, ethyl acetate/heptane gradient, 0:100 to 100:0). The desired (3RS)-3-hydroxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one (44 mg, 78% yield) was obtained as a white solid, MS: m/e=307.3 (M+H + ). 
       Example 15 
     4,4-Dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0408]    
       
                 
         
             
             
         
       
     
       Step 1: N-1-(5-Iodo-pyridin-2-yl)-2-methyl-propane-1,2-diamine 
       [0409]    
       
                 
         
             
             
         
       
     
         [0410]    The title compound was obtained as a colorless oil, MS: m/e=292.0 (M+H + ), using chemistry similar to that described in Example 1, step 1 from 2-fluoro-5-iodopyridine and 2-methylpropane-1,2-diamine. 
       Step 2: 1-(5-Iodo-pyridin-2-yl)-4,4-dimethyl-imidazolidin-2-one 
       [0411]    
       
                 
         
             
             
         
       
     
         [0412]    The title compound was obtained as a light yellow solid, MS: m/e=318.0 (M+H + ), using chemistry similar to that described in Example 1, step 2 from N-1-(5-iodo-pyridin-2-yl)-2-methyl-propane-1,2-diamine (Example 15, step 1). 
       Step 3: 4,4-Dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0413]    
       
                 
         
             
             
         
       
     
         [0414]    The title compound was obtained as a yellow solid, MS: m/e=292.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-imidazolidin-2-one (Example 15, step 2) and phenylacetylene. 
       Example 16 
     3,4,4-Trimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0415]    
       
                 
         
             
             
         
       
     
         [0416]    (110 mg, 378 μmol) 4,4-Dimethyl-1-(5-(phenylethynyl)pyridin-2-yl)imidazolidin-2-one (Example 15, step 3) was dissolved in DMF (0.5 ml) and cooled to 0-5° C. NaH (55%) (19.8 mg, 453 μmol, 1.2 equiv.) was added and the mixture was stirred for 30 min at 0-5° C. Iodomethane (35.3 μl, 566 μmol, 1.5 equiv.) was added and the mixture was stirred for 30 min at 0-5° C. The reaction mixture was treated with sat. NaHCO 3  solution and extracted twice with a small volume of CH 2 Cl 2 . The organic layers were loaded directly to silica gel column and the crude material was purified by flash chromatography on silica gel (20 gr, ethyl acetate/heptane gradient, 0:100 to 100:0). The desired 3,4,4-trimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one (93 mg, 81% yield) was obtained as a yellow solid, MS: m/e=306.2 (M+H + ). 
       Example 17 
     3-Ethyl-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0417]    
       
                 
         
             
             
         
       
     
         [0418]    The title compound was obtained as a yellow oil, MS: m/e=320.2 (M+H + ), using chemistry similar to that described in Example 16 starting from 4,4-dimethyl-1-(5-(phenylethynyl)pyridin-2-yl)imidazolidin-2-one (Example 15, step 3) and iodoethane. 
       Example 18 
     3-Isopropyl-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0419]    
       
                 
         
             
             
         
       
     
         [0420]    The title compound was obtained as a yellow oil, MS: m/e=334.3 (M+H + ), using chemistry similar to that described in Example 16 starting from 4,4-dimethyl-1-(5-(phenylethynyl)pyridin-2-yl)imidazolidin-2-one (Example 15, step 3) and 2-bromopropane. 
       Example 19 
     (5RS)-5-tert-Butyl-5-methyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0421]    
       
                 
         
             
             
         
       
     
       Step 1: 1-Dibenzylamino-3,3-dimethyl-butan-2-one 
       [0422]    
       
                 
         
             
             
         
       
     
         [0423]    (2.15 ml, 16.8 mmol) Dibenzylamine was dissolved in acetonitrile (30 ml). Potassium carbonate (2.3 g, 16.8 mmol, 1.5 equiv.) and 1-bromo-3,3-dimethylbutan-2-one (1.5 ml, 11.2 mmol, 1.0 equiv.) were added and the mixture was stirred for 16 hours at 90° C. The reaction mixture was extracted with sat. NaHCO 3 -solution and two times EtOAc. The organic layers were extracted with water, dried over Na 2 SO 4 , filtered and evaporated to dryness. The crude material was purified by flash chromatography on silica gel (70 gr, ethyl acetate/heptane gradient, 0:100 to 100:0). The desired 1-(dibenzylamino)-3,3-dimethylbutan-2-one (1.6 g, 48.5% yield) was obtained as a yellow oil, MS: m/e=296.3 (M+H + ). 
       Step 2: (RS)-1-Dibenzylamino-2,3,3-trimethyl-butan-2-ol 
       [0424]    
       
                 
         
             
             
         
       
     
         [0425]    (1.6 g, 5.4 mmol) 1-Dibenzylamino-3,3-dimethyl-butan-2-one (Example 19, step 1) was dissolved in diethylether (20 ml) and cooled to 0-5° C. Methylmagnesium bromide (3M in diethylether) (2.2 ml, 6.5 mmol, 1.2 equiv.) was added drop wise at 0-5° C. and the mixture was stirred for 72 hours at room temperature. The reaction mixture was extracted with sat. NH 4 Cl-solution and two times EtOAc. The organic layers were extracted with water, dried over Na 2 SO 4 , filtered and evaporated to dryness. The crude material was purified by flash chromatography on silica gel (50 gr, ethyl acetate/heptane gradient, 0:100 to 100:0). The desired (RS)-1-dibenzylamino-2,3,3-trimethyl-butan-2-ol (1.2 g, 71% yield) was obtained as a yellow oil, MS: m/e=312.4 (M+H + ). 
       Step 3: (RS)-1-Amino-2,3,3-trimethyl-butan-2-ol 
       [0426]    
       
                 
         
             
             
         
       
     
         [0427]    The title compound was obtained as a white solid, MS: m/e=132.1 (M+H + ), was prepared from (RS)-1-dibenzylamino-2,3,3-trimethyl-butan-2-ol (Example 19, step 2) by hydrogenation 16 hours at room temperature using Pd/C (10%) in ethyl acetate. 
       Step 4: (RS)-1-(5-Iodo-pyridin-2-ylamino)-2,3,3-trimethyl-butan-2-ol 
       [0428]    
       
                 
         
             
             
         
       
     
         [0429]    The title compound was obtained as a yellow solid, MS: m/e=335.1 (M+H + ), using chemistry similar to that described in Example 1, step 1 from 2-fluoro-5-iodopyridine and (RS)-1-amino-2,3,3-trimethyl-butan-2-ol (Example 19, step 3). 
       Step 5: (5RS)-5-tert-Butyl-3-(5-iodo-pyridin-2-yl)-5-methyl-oxazolidin-2-one 
       [0430]    
       
                 
         
             
             
         
       
     
         [0431]    The title compound was obtained as a yellow oil, MS: m/e=361.1 (M+H + ), using chemistry similar to that described in Example 1, step 2 from (RS)-1-(5-iodo-pyridin-2-ylamino)-2,3,3-trimethyl-butan-2-ol (Example 19, step 4). 
       Step 6: (5RS)-5-tert-Butyl-5-methyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0432]    
       
                 
         
             
             
         
       
     
         [0433]    The title compound was obtained as a light brown solid, MS: m/e=335.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (5RS)-5-tert-butyl-3-(5-iodo-pyridin-2-yl)-5-methyl-oxazolidin-2-one (Example 19, step 5) and phenylacetylene. 
       Example 20 
     5,5-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0434]    
       
                 
         
             
             
         
       
     
       Step 1: 3-(5-Iodo-pyridin-2-yl)-5,5-dimethyl-[1,3]oxazinan-2-one 
       [0435]    
       
                 
         
             
             
         
       
     
         [0436]    The title compound was obtained as a colorless oil, MS: m/e=333.1 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and 3-amino-2,2-dimethylpropan-1-ol. 
       Step 2: 5,5-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0437]    
       
                 
         
             
             
         
       
     
         [0438]    The title compound was obtained as a light brown oil, MS: m/e=307.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-5,5-dimethyl-[1,3]oxazinan-2-one (Example 20, step 1) and phenylacetylene. 
       Example 21 
     1-(3-Fluoro-5-phenylethynyl-pyridin-2-yl)-4,4-dimethyl-pyrrolidin-2-one 
       [0439]    
       
                 
         
             
             
         
       
     
         [0440]    The title compound was obtained as a orange solid, MS: m/e=309.2 (M+H + ), using procedures similar to those described in Example 13 by using 2-amino-3-fluoro-5-iodopyridine instead of 5-iodopyridin-2-amine. 
       Example 22 
     (3aRS,6aSR)-3-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one 
       [0441]    
       
                 
         
             
             
         
       
     
       Step 1: (3aRS,6aSR)-3-(5-Iodo-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one 
       [0442]    
       
                 
         
             
             
         
       
     
         [0443]    The title compound was obtained as a light brown solid, MS: m/e=331.1 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and (1SR,2RS)-2-aminocyclopentanol hydrochloride. 
       Step 2: (3aRS,6aSR)-3-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one 
       [0444]    
       
                 
         
             
             
         
       
     
         [0445]    The title compound was obtained as a light yellow solid, MS: m/e=305.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aRS,6aSR)-3-(5-iodo-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one (Example 13, step 1) and phenylacetylene. 
       Example 23 
     (3aRS,6aSR)-3-(5-Pyridin-3-ylethynyl-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one 
       [0446]    
       
                 
         
             
             
         
       
     
         [0447]    The title compound was obtained as a colorless oil, MS: m/e=306.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aRS,6aSR)-3-(5-iodo-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one (Example 13, step 1) and 3-ethynyl-pyridine. 
       Example 24 
     (3aRS,6aSR)-3-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-hexahydro-cyclopentaoxazol-2-one 
       [0448]    
       
                 
         
             
             
         
       
     
         [0449]    The title compound was obtained as a light brown solid, MS: m/e=324.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aRS,6aSR)-3-(5-iodo-pyridin-2-yl)-hexahydro-cyclopentaoxazol-2-one (Example 13, step 1) and 3-ethynyl-5-fluoro-pyridine (CAS 872122-54-8). 
       Example 25 
     5,5-Dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one 
       [0450]    
       
                 
         
             
             
         
       
     
         [0451]    The title compound was obtained as a light brown solid, MS: m/e=306.2 (M+H + ), using procedures similar to those described in Example 15 starting from 2-fluoro-5-iodopyridine and by using 2,2-dimethylpropane-1,3-diamine instead of 2-methylpropane-1,2-diamine. 
       Example 26 
     1,5,5-Trimethyl-3-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one 
       [0452]    
       
                 
         
             
             
         
       
     
         [0453]    The title compound was obtained as a light brown solid, MS: m/e=306.2 (M+H + ), using procedures similar to those described in Example 16 from 5,5-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one (Example 25) and iodomethane. 
       Example 27 
     (RS)-4,5,5-Trimethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0454]    
       
                 
         
             
             
         
       
     
         [0455]    The title compound was obtained as a yellow solid, MS: m/e=307.2 (M+H + ), using procedures similar to those described in Example 1 from 2-fluoro-5-iodopyridine and by using (RS)-3-amino-2-methyl-butan-2-ol (CAS 6291-17-4) instead of 1-amino-2-methylpropan-2-ol. 
       Example 28 
     4,4,5,5-Tetramethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0456]    
       
                 
         
             
             
         
       
     
         [0457]    The title compound was obtained as a light yellow solid, MS: m/e=321.2 (M+H + ), using procedures similar to those described in Example 1 from 2-fluoro-5-iodopyridine and by using 3-amino-2,3-dimethyl-butan-2-ol (CAS 89585-13-7) instead of 1-amino-2-methylpropan-2-ol. 
       Example 29 
     3-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one 
       [0458]    
       
                 
         
             
             
         
       
     
       Step 1: 5,5-Dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0459]    
       
                 
         
             
             
         
       
     
         [0460]    The title compound was obtained as a brown solid, MS: m/e=289.0 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one (Example 5, step 1) and ethynyltrimethylsilane. 
       Step 2: 3-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one 
       [0461]    
       
                 
         
             
             
         
       
     
         [0462]    5,5-Dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 29, step 1) (100 mg, 0.35 mmol) was dissolved in THF (3 ml). 3-Fluoro-5-iodopyridine (100 mg, 0.45 mmol, 1.3 equiv.), Et 3 N (145 μl, 1.04 mmol, 3 equiv.), Bis-(triphenylphosphine)-palladium(II)dichloride (10 mg, 14 μmol, 0.05 equiv.), triphenylphosphine (11 mg, 17 μmol, 0.05 equiv.), triphenylphosphine (3 mg, 10 μmol, 0.03 equiv.) and copper(I)iodide (1 mg, 3.5 mmol, 0.01 equiv.) were added under nitrogen and the mixture was heated to 60° C. TBAF 1M in THF (520 μl, 0.52 mmol, 1.5 equiv.) was added dropwise in 20 minutes at 60° C. The reaction mixture was stirred for 3 hours at 60° C. Sat. NaHCO 3  solution was added and the mixture was extracted with dichloromethane. The organic extracts were dried with sodium sulfate, filtered and evaporated. The crude product was purified by flash chromatography on silica gel (dichloromethane/methanol gradient 100:0 to 90:10). The desired 3-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one was obtained as a white solid (55 mg, 51% yield), MS: m/e=312.3 (M+H + ). 
       Example 30 
     5,5-Dimethyl-3-(5-pyrimidin-5-ylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0463]    
       
                 
         
             
             
         
       
     
         [0464]    The title compound was obtained as a light yellow solid, MS: m/e=295.2 (M+H + ), using chemistry similar to that described in Example 29, step 2 from 5,5-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 29, step 1) and 5-bromopyrimidine. 
       Example 31 
     5,5-Dimethyl-3-[5-(1-methyl-1H-pyrazol-4-ylethynyl)-pyridin-2-yl]-oxazolidin-2-one 
       [0465]    
       
                 
         
             
             
         
       
     
         [0466]    The title compound was obtained as a light yellow solid, MS: m/e=297.2 (M+H + ), using chemistry similar to that described in Example 29, step 2 from 5,5-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 29, step 1) and 4-iodo-1-methyl-1H-pyrazole. 
       Example 32 
       [0467]    3-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one 
         [0000]    
       
                 
         
             
             
         
       
     
         [0468]    The title compound was obtained as a yellow solid, MS: m/e=311.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-5,5-dimethyl-oxazolidin-2-one (Example 5, step 1) and 1-ethynyl-4-fluoro-benzene. 
       Example 33 
     3-[5-(3,4-Difluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one 
       [0469]    
       
                 
         
             
             
         
       
     
         [0470]    The title compound was obtained as a white solid, MS: m/e=329.2 (M+H + ), using chemistry similar to that described in Example 29, step 2 from 5,5-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 29, step 1) and 1,2-difluoro-4-iodobenzene. 
       Example 34 
     3-[5-(2,5-Difluoro-phenylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one 
       [0471]    
       
                 
         
             
             
         
       
     
         [0472]    The title compound was obtained as a white solid, MS: m/e=329.2 (M+H + ), using chemistry similar to that described in Example 29, step 2 from 5,5-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 29, step 1) and 1,4-difluoro-2-iodobenzene. 
       Example 35 
     3-[5-(6-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-5,5-dimethyl-oxazolidin-2-one 
       [0473]    
       
                 
         
             
             
         
       
     
         [0474]    The title compound was obtained as a white solid, MS: m/e=312.2 (M+H + ), using chemistry similar to that described in Example 29, step 2 from 5,5-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-oxazolidin-2-one (Example 29, step 1) and 2-fluoro-5-iodopyridine. 
       Example 36 
     6-(5-Pyridin-3-ylethynyl-pyridin-2-yl)-4-oxa-6-aza-spiro[2.4]heptan-5-one 
       [0475]    
       
                 
         
             
             
         
       
     
         [0476]    The title compound was obtained as a white solid, MS: m/e=292.2 (M+H + ), using procedures similar to those described in Example 1 starting from 2-fluoro-5-bromopyridine, 1-aminomethyl-cyclopropanol (Russian J. Org. Chem. 2001, 37, 1238) and 3-ethynyl-pyridine. 
       Example 37 
     1-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0477]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Bromo-5-trimethylsilanylethynyl-pyridine 
       [0478]    
       
                 
         
             
             
         
       
     
         [0479]    2-Bromo-5-iodopyridine (2.5 g, 8.8 mmol) was dissolved under nitrogen in 50 ml THF. Bis-(triphenylphosphine)-palladium(II)dichloride (618 mg, 880 μmol, 0.1 equiv.), ethynyltrimethylsilane (950 mg, 1.34 ml, 9.6 mmol, 1.1 equiv.), triethylamine (1.78 g, 2.44 ml, 17.6 mmol, 3 equiv.) and copper(I)iodide (84 mg, 440 μmol, 0.05 equiv.) were added and the mixture was stirred for 3 hours at 50° C. The reaction mixture was cooled and evaporated to dryness. The crude product was purified by flash chromatography on silica gel, eluting with an ethyl acetate:heptane gradient 0:100 to 15:85. The desired 2-bromo-5-trimethylsilanylethynyl-pyridine (1.95 g, 7.7 mmol, 87% yield) was obtained as a white solid, MS: m/e=254.1/256.1 (M+H + ). 
       Step 2: 4,4-Dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0480]    
       
                 
         
             
             
         
       
     
         [0481]    (260 mg, 1.0 mmol) 2-Bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) was dissolved in toluene (2 ml) and 4,4-dimethylpyrrolidin-2-one (115 mg, 1.0 mmol, 1.0 equiv.), cesium carbonate (660 mg, 2.05 mmol, 2.0 equiv.), xantphos (CAS 161265-03-8) (24 mg, 0.04 mmol, 0.04 equiv.) and Pd 2 (dba) 3  (19 mg, 0.02 mmol, 0.02 equiv.) were added under nitrogen. The mixture was stirred for 1 hour at 90° C. The crude product was purified by flash chromatography by directly loading the toluene mixture onto a silica gel column and eluting with an ethyl acetate:heptane gradient 0:100 to 40:60. The desired 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one (230 mg, 0.81 mmol, 75% yield) was obtained as a yellow solid, MS: m/e=287.1 (M+H + ). 
       Step 3: 1-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0482]    
       
                 
         
             
             
         
       
     
         [0483]    4,4-Dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 37, step 2) (80 mg, 0.28 mmol) was dissolved in DMF (1 ml). 3-Fluoro-5-iodopyridine (87 mg, 0.39 mmol, 1.4 equiv.), Et 3 N (85 mg, 117 μl, 0.84 mmol, 3 equiv.), Bis-(triphenylphosphine)-palladium(II)dichloride (10 mg, 14 μmol, 0.05 equiv.), triphenylphosphine (2 mg, 8.4 μmol, 0.03 equiv.) and copper(I)iodide (2 mg, 8.4 μmol, 0.03 equiv.) were added under nitrogen and the mixture was heated to 70° C. TBAF 1M in THF (300 μl, 0.3 mmol, 1.1 equiv.) was added dropwise in 20 minutes at 70° C. The reaction mixture was stirred for 30 minutes at 70° C. and evaporated with isolute to dryness. The crude product was purified by flash chromatography with a 20 g silica gel column and eluting with heptane:ethyl acetate 100:0-&gt;0:100. The desired 1-[5-(5-fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one (36 mg, 42% yield) was obtained as a white solid, MS: m/e=310.2 (M+H + ). 
       Example 38 
     4,4-Dimethyl-1-(5-pyridin-3-ylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0484]    
       
                 
         
             
             
         
       
     
         [0485]    The title compound was obtained as a white solid, MS: m/e=292.1 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 37, step 2) and 3-iodopyridine. 
       Example 39 
     1-[5-(5-Chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0486]    
       
                 
         
             
             
         
       
     
         [0487]    The title compound was obtained as a white solid, MS: m/e=326.2/328.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 37, step 2) and 3-chloro-5-iodopyridine. 
       Example 40 
     1-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0488]    
       
                 
         
             
             
         
       
     
         [0489]    The title compound was obtained as a white solid, MS: m/e=309.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 37, step 2) and 1-fluoro-3-iodobenzene. 
       Example 41 
     4,4-Dimethyl-1-(3-methyl-5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0490]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Bromo-3-methyl-5-trimethylsilanylethynyl-pyridine 
       [0491]    
       
                 
         
             
             
         
       
     
         [0492]    The title compound was obtained as a yellow oil, MS: m/e=268.1/270.1 (M+H + ), using chemistry similar to that described in Example 37, step 1 by using 2-bromo-5-iodo-3-methylpyridine instead of 2-bromo-5-iodopyridine. 
       Step 2: 4,4-Dimethyl-1-(3-methyl-5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0493]    
       
                 
         
             
             
         
       
     
         [0494]    The title compound was obtained as a brown solid, MS: m/e=301.3 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-3-methyl-5-trimethylsilanylethynyl-pyridine (Example 41, step 1) and 4,4-dimethylpyrrolidin-2-one. 
       Step 3: 4,4-Dimethyl-1-(3-methyl-5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0495]    
       
                 
         
             
             
         
       
     
         [0496]    The title compound was obtained as a white solid, MS: m/e=305.3 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-1-(3-methyl-5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 41, step 2) and iodobenzene. 
       Example 42 
     5,5-Dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0497]    
       
                 
         
             
             
         
       
     
       Step 1: 5,5-Dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0498]    
       
                 
         
             
             
         
       
     
         [0499]    The title compound was obtained as a yellow solid, MS: m/e=301.3 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and by using 5,5-dimethyl-piperidin-2-one (CAS 4007-79-8) instead of 4,4-dimethylpyrrolidin-2-one. 
       Step 2: 5,5-Dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0500]    
       
                 
         
             
             
         
       
     
         [0501]    The title compound was obtained as a yellow oil, MS: m/e=305.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 5,5-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 42, step 1) and iodobenzene. 
       Example 43 
     5′-(3-Fluoro-phenylethynyl)-5,5-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0502]    
       
                 
         
             
             
         
       
     
         [0503]    The title compound was obtained as a yellow oil, MS: m/e=323.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 5,5-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 42, step 1) and 1-fluoro-3-iodobenzene. 
       Example 44 
     1-Methyl-3-(5-phenylethynyl-pyridin-2-yl)-1,3-diaza-spiro[4.4]nonan-2-one 
       [0504]    
       
                 
         
             
             
         
       
     
       Step 1: {1-[(5-Iodo-pyridin-2-ylamino)-methyl]-cyclopentyl}-carbamic acid tert-butyl ester 
       [0505]    
       
                 
         
             
             
         
       
     
         [0506]    The title compound was obtained as a white solid, MS: m/e=418.2 (M+H + ), using chemistry similar to that described in Example 1, step 1 from 2-fluoro-5-iodopyridine and tert-1-butyl 1-(aminomethyl)cyclopentylcarbamate (CAS 889949-09-1) by using neat pyridine as solvent instead of NMP. 
       Step 2: (1-Amino-cyclopentylmethyl)-(5-iodo-pyridin-2-yl)-amine hydrochloride 
       [0507]    
       
                 
         
             
             
         
       
     
         [0508]    The BOC protecting group is removed by reacting {1-[(5-iodo-pyridin-2-ylamino)-methyl]-cyclopentyl}-carbamic acid tert-butyl ester (Example 44, step 1) with 4N HCl in dioxane for 1 hour at room temperature. The title compound was obtained by filtration of the hydrochloride salt as a light yellow solid, MS: m/e=318.1 (M+H + ). 
       Step 3: 3-(5-Iodo-pyridin-2-yl)-1,3-diaza-spiro[4.4]nonan-2-one 
       [0509]    
       
                 
         
             
             
         
       
     
         [0510]    The title compound was obtained as a white solid, MS: m/e=344.1 (M+H + ), using chemistry similar to that described in Example 1, step 2 from (1-amino-cyclopentylmethyl)-(5-iodo-pyridin-2-yl)-amine hydrochloride (Example 44, step 2). 
       Step 4: 3-(5-Phenylethynyl-pyridin-2-yl)-1,3-diaza-spiro[4,4]nonan-2-one 
       [0511]    
       
                 
         
             
             
         
       
     
         [0512]    The title compound was obtained as a light yellow solid, MS: m/e=318.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-1,3-diaza-spiro[4.4]nonan-2-one (Example 44, step 3) and phenylacetylene. 
       Step 5: 1-Methyl-3-(5-phenylethynyl-pyridin-2-yl)-1,3-diaza-spiro[4.4]nonan-2-one 
       [0513]    
       
                 
         
             
             
         
       
     
         [0514]    The title compound was obtained as a light yellow oil, MS: m/e=332.2 (M+H + ), using chemistry similar to that described in Example 16 from 3-(5-phenylethynyl-pyridin-2-yl)-1,3-diaza-spiro[4.4]nonan-2-one (Example 44, step 4) and iodomethane. 
       Example 45 
     (RS)-4-Cyclopentyl-3-methyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0515]    
       
                 
         
             
             
         
       
     
         [0516]    The title compound was obtained as a light yellow solid, MS: m/e=346.2 (M+H + ), using procedures similar to those described in Example 44 from 2-fluoro-5-iodopyridine and by using (RS)-tert-butyl 2-amino-1-cyclopentylethylcarbamate (CAS 936497-76-6) instead of tert-butyl 1-(aminomethyl)cyclopentylcarbamate. 
       Example 46 
     (1RS,5SR)-6-(5-Phenylethynyl-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one 
       [0517]    
       
                 
         
             
             
         
       
     
       Step 1: (1RS,5SR)-6-(5-Bromo-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one 
       [0518]    
       
                 
         
             
             
         
       
     
         [0519]    The title compound was obtained as a white solid, MS: m/e=268.2 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2,5-dibromopyridine and (1RS,5SR)-6-aza-bicyclo[3.2.0]heptan-7-one (CAS 22031-52-3). 
       Step 2: (1RS,5SR)-6-(5-Phenylethynyl-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one 
       [0520]    
       
                 
         
             
             
         
       
     
         [0521]    The title compound was obtained as a brown solid, MS: m/e=289.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (1RS,5SR)-6-(5-bromo-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one (Example 46, step 1) with phenylacetylene. 
       Example 47 
     (6SR,7RS)-3-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-benzooxazol-2-one 
       [0522]    
       
                 
         
             
             
         
       
     
         [0523]    The title compound was obtained as a yellow solid, MS: m/e=319.2 (M+H + ), using procedures similar to those described in Example 1 starting from 2-fluoro-5-bromopyridine, (5SR,6RS)-2-amino-cyclohexanol hydrochloride (CAS 190792-72-4) and phenylacetylene. 
       Example 48 
     3,4,4-Trimethyl-1-(5-pyridin-3-ylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0524]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one 
       [0525]    
       
                 
         
             
             
         
       
     
         [0526]    The title compound was obtained as a light yellow solid, MS: m/e=332.1 (M+H + ), using chemistry similar to that described in Example 16 from 1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-imidazolidin-2-one (Example 15, step 2) and iodomethane. 
       Step 2: 3,4,4-Trimethyl-1-(5-pyridin-3-ylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0527]    
       
                 
         
             
             
         
       
     
         [0528]    The title compound was obtained as a white solid, MS: m/e=307.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 48, step 1) and 3-ethynyl-pyridine. 
       Example 49 
     1-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0529]    
       
                 
         
             
             
         
       
     
       Step 1: 3,4,4-Trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0530]    
       
                 
         
             
             
         
       
     
         [0531]    The title compound was obtained as a yellow solid, MS: m/e=302.3 (M+H + ), using chemistry similar to that described in Example 37, step 1 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 48, step 1) and ethynyltrimethylsilane. 
       Step 2: 1-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0532]    
       
                 
         
             
             
         
       
     
         [0533]    The title compound was obtained as a light yellow solid, MS: m/e=325.4 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 3,4,4-trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one (Example 49, step 1) and 3-fluoro-5-iodopyridine. 
       Example 50 
     3,4,4-Trimethyl-1-[5-(1-methyl-1H-pyrazol-4-ylethynyl)-pyridin-2-yl]-imidazolidin-2-one 
       [0534]    
       
                 
         
             
             
         
       
     
         [0535]    The title compound was obtained as a light yellow solid, MS: m/e=310.3 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 3,4,4-trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one (Example 49, step 1) and 4-iodo-1-methyl-1H-pyrazole. 
       Example 51 
     1-[5-(5-Chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0536]    
       
                 
         
             
             
         
       
     
         [0537]    The title compound was obtained as a white solid, MS: m/e=341.1/343.3 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 3,4,4-trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one (Example 49, step 1) and 3-chloro-5-iodopyridine. 
       Example 52 
     3,4,4-Trimethyl-1-(5-pyridazin-4-ylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0538]    
       
                 
         
             
             
         
       
     
         [0539]    The title compound was obtained as a light yellow solid, MS: m/e=308.4 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 3,4,4-trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one (Example 49, step 1) and 4-bromo-pyridazine. 
       Example 53 
     1-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0540]    
       
                 
         
             
             
         
       
     
         [0541]    The title compound was obtained as a yellow solid, MS: m/e=324.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 48, step 1) and 1-ethynyl-3-fluoro-benzene. 
       Example 54 
     1-[5-(3-Chloro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0542]    
       
                 
         
             
             
         
       
     
         [0543]    The title compound was obtained as a yellow solid, MS: m/e=340.1/342.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 48, step 1) and 1-ethynyl-3-chloro-benzene. 
       Example 55 
     3,4,4-Trimethyl-1-(5-pyrimidin-5-ylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0544]    
       
                 
         
             
             
         
       
     
         [0545]    The title compound was obtained as a light yellow solid, MS: m/e=308.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 3,4,4-trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one (Example 49, step 1) and 5-bromo-pyrimidine. 
       Example 56 
     3,4,4-Trimethyl-1-(5-m-tolylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0546]    
       
                 
         
             
             
         
       
     
         [0547]    The title compound was obtained as a brown oil, MS: m/e=320.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 48, step 1) and 1-ethynyl-3-methyl-benzene. 
       Example 57 
     1-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0548]    
       
                 
         
             
             
         
       
     
         [0549]    The title compound was obtained as a light brown solid, MS: m/e=324.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 48, step 1) and 1-ethynyl-4-fluoro-benzene. 
       Example 58 
     (RS)-2-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one 
       [0550]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-2-(5-Iodo-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one 
       [0551]    
       
                 
         
             
             
         
       
     
         [0552]    The title compound was obtained as a white solid, MS: m/e=344.0 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and (RS)-hexahydro-imidazo[1,5-a]pyridin-3-one (CAS 76561-92-7) by using neat pyridine as solvent instead of NMP. 
       Step 2: (RS)-2-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one 
       [0553]    
       
                 
         
             
             
         
       
     
         [0554]    The title compound was obtained as a white solid, MS: m/e=318.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-2-(5-iodo-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one (Example 58, step 1) and phenylacetylenen. 
       Example 59 
     2-(5-Phenylethynyl-pyridin-2-yl)-2-aza-spiro[4.4]nonan-3-one 
       [0555]    
       
                 
         
             
             
         
       
     
         [0556]    The title compound was obtained as a light yellow, MS: m/e=317.2 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-phenylethynyl-pyridine (Example 58, step 1) and 2-aza-spiro[4.4]nonan-3-one (CAS 75751-72-3). 
       Example 60 
     (RS)-3-Methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0557]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-4-Iodo-N-(5-iodo-pyridin-2-yl)-2-methoxy-3,3-dimethyl-butyramide 
       [0558]    
       
                 
         
             
             
         
       
     
         [0559]    The title compound was obtained as a white solid, MS: m/e=474.9 (M+H + ), using chemistry similar to that described in patent WO9637466, page 17, step 2 starting from (RS)-3-methoxy-4,4-dimethyl-dihydro-furan-2-one (CAS 100101-82-4) instead of 3-t-butylcarbamoyloxy-tetrahydrofuran-2-one and by using 2-amino-5-iodopyridine instead of 2-amino-4-trifluoromethylpyridine. 
       Step 2: (RS)-1-(5-Iodo-pyridin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0560]    
       
                 
         
             
             
         
       
     
         [0561]    The title compound was obtained as a light yellow solid, MS: m/e=347.0 (M+H + ), using chemistry similar to that described in patent WO9637466, page 17, step 3 from (RS)-4-iodo-N-(5-iodo-pyridin-2-yl)-2-methoxy-3,3-dimethyl-butyramide (Example 60, step 1). 
       Step 3: (RS)-3-Methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0562]    
       
                 
         
             
             
         
       
     
         [0563]    The title compound was obtained as a light yellow solid, MS: m/e=321.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-1-(5-iodo-pyridin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 60, step 2) and phenylacetylene. 
       Example 61 
     (5R or 5S)-5-Methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0564]    
       
                 
         
             
             
         
       
     
         [0565]    The title compound, a yellow oil, MS: m/e=321.3 (M+H + ), was prepared by separation of (RS)-3-methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 60) using a chiral column (chiralpak AD with heptane:isopropanol 90:10 as solvent). 
       Example 62 
     (5S or 5R)-5-Methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-oxazolidin-2-one 
       [0566]    
       
                 
         
             
             
         
       
     
         [0567]    The title compound, a white solid, MS: m/e=321.3 (M+H + ), was prepared by separation of (RS)-3-methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 60) using a chiral column (chiralpak AD with heptane:isopropanol 90:10 as solvent). 
       Example 63 
     (RS)-1-[5-(5-Chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0568]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-3-Methoxy-4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0569]    
       
                 
         
             
             
         
       
     
         [0570]    The title compound was obtained as a yellow solid, MS: m/e=317.2 (M+H + ), using chemistry similar to that described in Example 37, step 1 from (RS)-1-(5-iodo-pyridin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 60, step 2) and ethynyltrimethylsilane. 
       Step 2: (RS)-1-[5-(5-Chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0571]    
       
                 
         
             
             
         
       
     
         [0572]    The title compound was obtained as a white solid, MS: m/e=356.1/358.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from (RS)-3-methoxy-4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-pyrrolidin-2-one (Example 63, step 1) and 3-chloro-5-iodopyridine. 
       Example 64 
     (RS)-3-Methoxy-4,4-dimethyl-1-(5-m-tolylethynyl-pyridin-2-yl)-pyrrolidin-2-one 
       [0573]    
       
                 
         
             
             
         
       
     
         [0574]    The title compound was obtained as an orange oil, MS: m/e=335.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-1-(5-iodo-pyridin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 60, step 2) and 1-ethynyl-3-methyl-benzene. 
       Example 65 
     (RS)-1-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0575]    
       
                 
         
             
             
         
       
     
         [0576]    The title compound was obtained as a brown solid, MS: m/e=339.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-1-(5-iodo-pyridin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 60, step 2) and 1-ethynyl-3-fluorobenzene. 
       Example 66 
     (RS)-1-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0577]    
       
                 
         
             
             
         
       
     
         [0578]    The title compound was obtained as a brown solid, MS: m/e=339.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-1-(5-iodo-pyridin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 60, step 2) and 1-ethynyl-4-fluorobenzene. 
       Example 67 
     3,4,4-Trimethyl-1-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one 
       [0579]    
       
                 
         
             
             
         
       
     
       Step 1: [3-(5-Iodo-pyridin-2-ylamino)-1,1-dimethyl-propyl]-carbamic acid tert-butyl ester 
       [0580]    
       
                 
         
             
             
         
       
     
         [0581]    The title compound was obtained as a white solid, MS: m/e=406.3 (M+H + ), using chemistry similar to that described in Example 1, step 1 from 2-fluoro-5-iodopyridine and tert-butyl 4-amino-2-methylbutan-2-ylcarbamate (CAS 880100-43-6). 
       Step 2: N-1-(5-Iodo-pyridin-2-yl)-3-methyl-butane-1,3-diamine hydrochloride 
       [0582]    
       
                 
         
             
             
         
       
     
         [0583]    The BOC protecting group is removed by reacting [3-(5-iodo-pyridin-2-ylamino)-1,1-dimethyl-propyl]-carbamic acid tert-butyl ester (Example 67, step 1) with 4N HCl in dioxane for 4 hours at room temperature. The title compound was obtained by filtration of the hydrochloride salt as a pink solid, MS: m/e=306.1 (M+H + ). 
       Step 3: 1-(5-Iodo-pyridin-2-yl)-4,4-dimethyl-tetrahydro-pyrimidin-2-one 
       [0584]    
       
                 
         
             
             
         
       
     
         [0585]    The title compound was obtained as a yellow solid, MS: m/e=332.1 (M+H + ), using chemistry similar to that described in Example 1, step 2 from N-1-(5-iodo-pyridin-2-yl)-3-methyl-butane-1,3-diamine hydrochloride (Example 67, step 2). 
       Step 4: 1-(5-Iodo-pyridin-2-yl)-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one 
       [0586]    
       
                 
         
             
             
         
       
     
         [0587]    The title compound was obtained as a yellow solid, MS: m/e=346.0 (M+H + ), using chemistry similar to that described in Example 16 from 1-(5-iodo-pyridin-2-yl)-4,4-dimethyl-tetrahydro-pyrimidin-2-one (Example 67, step 3) and iodomethane. 
       Step 5: 3,4,4-Trimethyl-1-(5-phenylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one 
       [0588]    
       
                 
         
             
             
         
       
     
         [0589]    The title compound was obtained as a brown solid, MS: m/e=320.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one (Example 67, step 4) and phenylacetylene. 
       Example 68 
     1-[5-(2,5-Difluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one 
       [0590]    
       
                 
         
             
             
         
       
     
       Step 1: 3,4,4-Trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one 
       [0591]    
       
                 
         
             
             
         
       
     
         [0592]    The title compound was obtained as a white solid, MS: m/e=316.2 (M+H + ), using chemistry similar to that described in Example 37, step 1 from 1-(5-iodo-pyridin-2-yl)-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one (Example 67, step 4) and ethynyltrimethylsilane. 
       Step 2: 1-[5-(2,5-Difluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one 
       [0593]    
       
                 
         
             
             
         
       
     
         [0594]    The title compound was obtained as a light yellow solid, MS: m/e=356.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 3,4,4-trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one (Example 68, step 1) and 1,4-difluoro-2-iodobenzene. 
       Example 69 
     1-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-tetrahydro-pyrimidin-2-one 
       [0595]    
       
                 
         
             
             
         
       
     
         [0596]    The title compound was obtained as a white solid, MS: m/e=338.3 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 3,4,4-trimethyl-1-(5-trimethylsilanylethynyl-pyridin-2-yl)-tetrahydro-pyrimidin-2-one (Example 68, step 1) and 1-fluoro-4-iodobenzene. 
       Example 70 
     (RS)-2-(5-Pyridin-3-ylethynyl-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one 
       [0597]    
       
                 
         
             
             
         
       
     
         [0598]    The title compound was obtained as a light yellow solid, MS: m/e=319.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-2-(5-iodo-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one (Example 58, step 1) and 3-ethynyl-pyridine. 
       Example 71 
     (RS)-2-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-hexahydro-imidazo[1,5-a]pyridin-3-one 
       [0599]    
       
                 
         
             
             
         
       
     
         [0600]    The title compound was obtained as a light brown solid, MS: m/e=336.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-2-(5-iodo-pyridin-2-yl)-hexahydro-imidazo[1,5-a]pyridin-3-one (Example 58, step 1) and 1-ethynyl-3-fluorobenzene. 
       Example 72 
     6,6-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0601]    
       
                 
         
             
             
         
       
     
       Step 1: (3-Hydroxy-3-methyl-butyl)-carbamic acid benzyl ester 
       [0602]    
       
                 
         
             
             
         
       
     
         [0603]    (10 g, 42.1 mmol) Methyl 3-(benzyloxycarbonylamino)propanoate (CAS 54755-77-0) was dissolved in THF (150 ml) and cooled to 0-5° C. 3N Methylmagnesium bromide in THF (56.2 ml, 120 mmol, 4 equiv.) was added drop wise and the mixture stirred for 1 hour at 0-5° C. The reaction mixture was extracted with saturated NH 4 Cl solution and two times with EtOAc. The organic layers were dried over Na 2 SO 4  and evaporated to dryness. The desired (3-hydroxy-3-methyl-butyl)-carbamic acid benzyl ester (11.6 g, quant.) was obtained as a colorless oil, MS: m/e=238.1 (M+H + ) and used in the next step without further purification. 
       Step 2: 6,6-dimethyl-[1,3]oxazinan-2-one 
       [0604]    
       
                 
         
             
             
         
       
     
         [0605]    (11.6 g, 48.9 mmol) (3-Hydroxy-3-methyl-butyl)-carbamic acid benzyl ester (Example 72, step 1) was dissolved in THF (250 ml) and sodium hydride (60%, 5.2 g, 108 mmol, 2.2 equiv.) was added in portions. The mixture was stirred for 3 hours at room temperature. 5 ml saturated NaHCO 3  solution was added carefully and the mixture was evaporated with isolute to dryness. The crude product was purified by flash chromatography by directly loading the residue onto a silica gel column and eluting with an ethyl acetate:methanol gradient 100:0 to 90:10. The desired 6,6-dimethyl-[1,3]oxazinan-2-one (3.2 g, 51% yield) was obtained as a yellow solid, MS: m/e=130.1 (M+H + ). 
       Step 3: 6,6-Dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0606]    
       
                 
         
             
             
         
       
     
         [0607]    The title compound was obtained as an orange solid, MS: m/e=303.2 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and by using 6,6-dimethyl-[1,3]oxazinan-2-one (Example 72, step 2) instead of 4,4-dimethylpyrrolidin-2-one. 
       Step 4: 6,6-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0608]    
       
                 
         
             
             
         
       
     
         [0609]    The title compound was obtained as a yellow solid, MS: m/e=307.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 72, step 3) and iodobenzene. 
       Example 73 
     6,6-Dimethyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0610]    
       
                 
         
             
             
         
       
     
       Step 1: 3-(5-Iodo-pyridin-2-yl)-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0611]    
       
                 
         
             
             
         
       
     
         [0612]    The title compound was obtained as a white solid, MS: m/e=333.1 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and 4-amino-2-methyl-butan-2-ol hydrochloride. 
       Step 2: 6,6-Dimethyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0613]    
       
                 
         
             
             
         
       
     
         [0614]    The title compound was obtained as a light yellow solid, MS: m/e=308.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-6,6-dimethyl-[1,3]oxazinan-2-one (Example 73, step 1) and phenylacetylene. 
       Example 74 
     3-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0615]    
       
                 
         
             
             
         
       
     
         [0616]    The title compound was obtained as a white solid, MS: m/e=326.3 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 72, step 3) and 3-fluoro-5-iodopyridine. 
       Example 75 
     3-[5-(5-Chloro-pyridin-3-ylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0617]    
       
                 
         
             
             
         
       
     
         [0618]    The title compound was obtained as a white solid, MS: m/e=342.1/344.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 72, step 3) and 3-chloro-5-iodopyridine. 
       Example 76 
     3-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0619]    
       
                 
         
             
             
         
       
     
         [0620]    The title compound was obtained as a white solid, MS: m/e=325.4 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 72, step 3) and 1-fluoro-3-iodobenzene. 
       Example 77 
     3-[5-(3-Chloro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0621]    
       
                 
         
             
             
         
       
     
         [0622]    The title compound was obtained as a white solid, MS: m/e=341.2/343.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 72, step 3) and 1-chloro-3-iodobenzene. 
       Example 78 
     6,6-Dimethyl-3-(5-m-tolylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0623]    
       
                 
         
             
             
         
       
     
         [0624]    The title compound was obtained as a light yellow solid, MS: m/e=321.4 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 72, step 3) and 1-iodo-3-methylbenzene. 
       Example 79 
     3-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0625]    
       
                 
         
             
             
         
       
     
         [0626]    The title compound was obtained as a light brown solid, MS: m/e=325.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-6,6-dimethyl-[1,3]oxazinan-2-one (Example 73, step 1) and 1-ethynyl-4-fluorobenzene. 
       Example 80 
     3-[5-(3,4-Difluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0627]    
       
                 
         
             
             
         
       
     
         [0628]    The title compound was obtained as a light yellow solid, MS: m/e=343.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-6,6-dimethyl-[1,3]oxazinan-2-one (Example 73, step 1) and 4-ethynyl-1,2-difluorobenzene. 
       Example 81 
     3-[5-(2,5-Difluoro-phenylethynyl)-pyridin-2-yl]-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0629]    
       
                 
         
             
             
         
       
     
         [0630]    The title compound was obtained as a light yellow solid, MS: m/e=343.1 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 72, step 3) and 1,4-difluoro-2-iodobenzene. 
       Example 82 
     6-(5-Phenylethynyl-pyridin-2-yl)-2-oxa-6-aza-spiro[3.4]octan-7-one 
       [0631]    
       
                 
         
             
             
         
       
     
       Step 1: 6-(5-Trimethylsilanylethynyl-pyridin-2-yl)-2-oxa-6-aza-spiro[3.4]octan-7-one 
       [0632]    
       
                 
         
             
             
         
       
     
         [0633]    The title compound was obtained as a white solid, MS: m/e=301.3 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and 2-oxa-6-aza-spiro[3.4]octan-7-one (CAS 1207174-87-5). 
       Step 2: 6-(5-Phenylethynyl-pyridin-2-yl)-2-oxa-6-aza-spiro[3.4]octan-7-one 
       [0634]    
       
                 
         
             
             
         
       
     
         [0635]    The title compound was obtained as a light yellow solid, MS: m/e=305.3 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6-(5-trimethylsilanylethynyl-pyridin-2-yl)-2-oxa-6-aza-spiro[3.4]octan-7-one (Example 82, step 1) and iodobenzene. 
       Example 83 
     (RS)-4-Cyclopropyl-3-methyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0636]    
       
                 
         
             
             
         
       
     
         [0637]    The title compound was obtained as an orange solid, MS: m/e=318.1 (M+H + ), using procedures similar to those described in Example 58 from 2-fluoro-5-iodopyridine and by using (RS)-1-cyclopropyl-ethane-1,2-diamine instead of (RS)-hexahydro-imidazo[1,5-a]pyridin-3-one. 
       Example 84 
     (3aSR,7aRS)-(3 aRS,7RS)-1-Methyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0638]    
       
                 
         
             
             
         
       
     
       Step 1: (1SR,2RS)-(1RS,2RS)—N-(5-Iodo-pyridin-2-yl)-cyclohexane-1,2-diamine 
       [0639]    
       
                 
         
             
             
         
       
     
         [0640]    The title compound was obtained as a brown oil, MS: m/e=318.1 (M+H + ), using chemistry similar to that described in Example 1, step 1 from 2-fluoro-5-iodopyridine and rac-cyclohexane-1,2-diamine. 
       Step 2: (3aSR,7aRS)-(3aRS,7aRS)-1-(5-Iodo-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0641]    
       
                 
         
             
             
         
       
     
         [0642]    The title compound was obtained as a yellow solid, MS: m/e=344.1 (M+H + ), using chemistry similar to that described in Example 1, step 2 from (1SR,2RS)-(1RS,2RS)—N-(5-iodo-pyridin-2-yl)-cyclohexane-1,2-diamine (Example 84, step 1). 
       Step 3: (3aSR,7aRS)-(3aRS,7aRS)-1-(5-Iodo-pyridin-2-yl)-3-methyl-octahydro-benzoimidazol-2-one 
       [0643]    
       
                 
         
             
             
         
       
     
         [0644]    The title compound was obtained as a white solid, MS: m/e=358.0 (M+H + ), using chemistry similar to that described in Example 16 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-octahydro-benzoimidazol-2-one (Example 84, step 2) and iodomethane. 
       Step 4: (3aSR,7aRS)-(3aRS,7RS)-1-Methyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0645]    
       
                 
         
             
             
         
       
     
         [0646]    The title compound was obtained as a yellow solid, MS: m/e=332.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-3-methyl-octahydro-benzoimidazol-2-one (Example 84, step 3) and phenylacetylene. 
       Example 85 
     (3aSR,7aRS)-(3aRS,7RS)-1-Methyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0647]    
       
                 
         
             
             
         
       
     
         [0648]    The title compound was obtained as a light yellow solid, MS: m/e=333.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-3-methyl-octahydro-benzoimidazol-2-one (Example 84, step 3) and 3-ethynylpyridine. 
       Example 86 
     (3aSR,7aRS)-(3aRS,7RS)-1-[5-(5-Fluoro-pyridin-3-ylethynyl)-pyridin-2-yl]-3-methyl-octahydro-benzoimidazol-2-one 
       [0649]    
       
                 
         
             
             
         
       
     
         [0650]    The title compound was obtained as a light yellow solid, MS: m/e=351.3 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-3-methyl-octahydro-benzoimidazol-2-one (Example 84, step 3) and 3-ethynyl-5-fluoro-pyridine (generated by in situ Sonogashira reaction of 3-fluoro-5-iodopyridine with ethynyltrimethylsilane and TBAF). 
       Example 87 
     4,4-Dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0651]    
       
                 
         
             
             
         
       
     
       Step 1: 4,4-Dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0652]    
       
                 
         
             
             
         
       
     
         [0653]    The title compound was obtained as a yellow solid, MS: m/e=301.3 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and by using 4,4-dimethyl-piperidin-2-one (CAS 55047-81-9) instead of 4,4-dimethylpyrrolidin-2-one. 
       Step 2: 4,4-Dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0654]    
       
                 
         
             
             
         
       
     
         [0655]    The title compound was obtained as a white solid, MS: m/e=305.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 87, step 1) and iodobenzene. 
       Example 88 
     5′-(3-Fluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0656]    
       
                 
         
             
             
         
       
     
         [0657]    The title compound was obtained as a white solid, MS: m/e=323.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 87, step 1) and 1-fluoro-3-iodobenzene. 
       Example 89 
     5′-(3-Chloro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0658]    
       
                 
         
             
             
         
       
     
         [0659]    The title compound was obtained as a light yellow solid, MS: m/e=339.2/341.1 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 87, step 1) and 1-chloro-3-iodobenzene. 
       Example 90 
     5′-(5-Chloro-pyridin-3-ylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0660]    
       
                 
         
             
             
         
       
     
         [0661]    The title compound was obtained as a light yellow solid, MS: m/e=340.1/342.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 87, step 1) and 1-chloro-3-iodopyridine. 
       Example 91 
     5′-(4-Fluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0662]    
       
                 
         
             
             
         
       
     
         [0663]    The title compound was obtained as a light yellow solid, MS: m/e=323.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 87, step 1) and 1-fluoro-4-iodobenzene. 
       Example 92 
     5′-(2,5-Difluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one 
       [0664]    
       
                 
         
             
             
         
       
     
         [0665]    The title compound was obtained as a white solid, MS: m/e=341.1 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyridinyl-2-one (Example 87, step 1) and 1,4-difluoro-2-iodobenzene. 
       Example 93 
     7,7-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazepan-2-one 
       [0666]    
       
                 
         
             
             
         
       
     
       Step 1: 3-(5-Iodo-pyridin-2-yl)-7,7-dimethyl-[1,3]oxazepan-2-one 
       [0667]    
       
                 
         
             
             
         
       
     
         [0668]    The title compound was obtained as a colorless oil, MS: m/e=346.9 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and 5-amino-2-methylpentan-2-ol (CAS 108262-66-4). 
       Step 2: 7,7-Dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazepan-2-one 
       [0669]    
       
                 
         
             
             
         
       
     
         [0670]    The title compound was obtained as an orange solid, MS: m/e=321.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 3-(5-iodo-pyridin-2-yl)-7,7-dimethyl-[1,3]oxazepan-2-one (Example 93, step 1) and phenylacetylene. 
       Example 94 
     (3aSR,7aRS)-(3aRS,7RS)-1-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-pyrano[4,3-d]oxazol-2-one 
       [0671]    
       
                 
         
             
             
         
       
     
       Step 1: (3aSR,7aRS)-(3aRS,7RS)-1-(5-Iodo-pyridin-2-yl)-hexahydro-pyrano[4,3-d]oxazol-2-one 
       [0672]    
       
                 
         
             
             
         
       
     
         [0673]    The title compound was obtained as a white solid, MS: m/e=346.9 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and (3RS,4RS)-(3RS,4SR)-4-aminotetrahydro-2H-pyran-3-ol (CAS 33332-01-3). 
       Step 2: (3aSR,7aRS)-(3aRS,7RS)-1-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-pyrano[4,3-d]oxazol-2-one 
       [0674]    
       
                 
         
             
             
         
       
     
         [0675]    The title compound was obtained as a brown solid, MS: m/e=321.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aSR,7aRS)-(3aRS,7RS)-1-(5-iodo-pyridin-2-yl)-hexahydro-pyrano[4,3-d]oxazol-2-one (Example 94, step 1) and phenylacetylene. 
       Example 95 
     (RS)-5-Hydroxy-6,6-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0676]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-2-(tert-Butyl-diphenyl-silanyloxy)-3-dibenzylamino-propionic acid ethyl ester 
       [0677]    
       
                 
         
             
             
         
       
     
         [0678]    (5.8 g, 18.6 mmol) (RS)-3-Dibenzylamino-2-hydroxy-propionic acid ethyl ester (CAS 93715-75-4) was dissolved in DMF (40 ml) and tert-butylchlorodiphenylsilane (6.76 ml, 26 mmol, 1.4 equiv.), Imidazole (1.9 g, 27.9 mmol, 1.5 equiv.) and DMAP (227 mg, 1.9 mmol, 0.1 equiv.) were added at room temperature. The mixture was stirred for 3 hours at 80° C. The reaction mixture was evaporated and extracted with saturated NaHCO 3  solution and two times with EtOAc. The organic layers were extracted with brine, dried over Na 2 SO 4  and evaporated to dryness. The crude product was purified by flash chromatography on silica gel column and eluting with an ethyl acetate:heptane gradient 0:100 to 40:60. The desired (RS)-2-(tert-butyl-diphenyl-silanyloxy)-3-dibenzylamino-propionic acid ethyl ester (8.1 g, 79% yield) was obtained as a colorless oil, MS: m/e=552.5 (M+H + ). 
       Step 2: (RS)-3-(tert-Butyl-diphenyl-silanyloxy)-4-dibenzylamino-2-methyl-butan-2-ol 
       [0679]    
       
                 
         
             
             
         
       
     
         [0680]    (8.0 g, 14.5 mmol) (RS)-2-(tert-Butyl-diphenyl-silanyloxy)-3-dibenzylamino-propionic acid ethyl ester (Example 95, step 1) was dissolved in THF (100 ml) and methylmagnesium bromide (3M in diethylether) (19.3 ml, 58 mmol, 4 equiv.) was drop wise at room temperature. The mixture was stirred for 3.5 hours at room temperature. The reaction mixture was extracted with saturated NaHCO 3  solution and two times with EtOAc. The organic layers were extracted with brine, dried over Na 2 SO 4  and evaporated to dryness. The desired (RS)-3-(tert-butyl-diphenyl-silanyloxy)-4-dibenzylamino-2-methyl-butan-2-ol (6.9 g, 84% yield) was obtained as a white solid, MS: m/e=538.5 (M+H + ) and used in the next step without further purification. 
       Step 3: (RS)-4-Amino-3-(tert-butyl-diphenyl-silanyloxy)-2-methyl-butan-2-ol 
       [0681]    
       
                 
         
             
             
         
       
     
         [0682]    (RS)-3-(tert-Butyl-diphenyl-silanyloxy)-4-dibenzylamino-2-methyl-butan-2-ol (Example 95, step 2) was hydrogenated in EtOH with Pd(OH) 2  for 16 hours at 60° C. The desired (RS)-4-amino-3-(tert-butyl-diphenyl-silanyloxy)-2-methyl-butan-2-ol (4.2 g, 92% yield) was obtained as a colorless oil, MS: m/e=358.2 (M+H + ) and used in the next step without further purification. 
       Step 4: (RS)-5-(2,2-Dimethyl-1,1-diphenyl-propoxy)-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0683]    
       
                 
         
             
             
         
       
     
         [0684]    (1.83 mg, 5.1 mmol) (RS)-4-Amino-3-(tert-butyl-diphenyl-silanyloxy)-2-methyl-butan-2-ol (Example 95, step 3) was dissolved in THF (35 ml) and cooled to 0-5° C. Triethylamine (2.14 ml, 15.4 mmol, 3 equiv.) and triphosgene (1.67 g, 5.63 mmol, 1.1 equiv.) dissolved in 15 ml THF were added drop wise at 0-5° C. The mixture was stirred for 1 hour at 0-5° C. The reaction mixture was evaporated with isolute and the crude product was purified by flash chromatography by directly loading the residue onto a silica gel column and eluting with a heptane:ethyl acetate gradient 100:0 to 0:100. The desired (RS)-5-(2,2-dimethyl-1,1-diphenyl-propoxy)-6,6-dimethyl-[1,3]oxazinan-2-one (535 mg, 27% yield) was obtained as a white solid, MS: m/e=384.3 (M+H + ). 
       Step 5: (RS)-5-(2,2-Dimethyl-1,1-diphenyl-propoxy)-6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0685]    
       
                 
         
             
             
         
       
     
         [0686]    The title compound was obtained as a yellow oil, MS: m/e=557.3 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and (RS)-5-(2,2-dimethyl-1,1-diphenyl-propoxy)-6,6-dimethyl-[1,3]oxazinan-2-one (Example 95, step 4). 
       Step 6: (RS)-5-Hydroxy-6,6-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0687]    
       
                 
         
             
             
         
       
     
         [0688]    The title compound was obtained as a light yellow solid, MS: m/e=323.1 (M+H + ), using chemistry similar to that described in Example 37, step 3 from (RS)-5-(2,2-dimethyl-1,1-diphenyl-propoxy)-6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 95, step 5) and iodobenzene. 
       Example 96 
     4-Methyl-6-(5-phenylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one 
       [0689]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Bromo-5-phenylethynyl-pyridine 
       [0690]    
       
                 
         
             
             
         
       
     
         [0691]    The title compound was obtained as a white solid, MS: m/e=258/260 (M+H + ), using chemistry similar to that described in Example 37, step 1 from 2-bromo-5-iodopyridine and by using phenylacetylene instead of ethynyltrimethylsilane. 
       Step 2: 4,6-Diaza-spiro[2.4]heptan-5-one 
       [0692]    
       
                 
         
             
             
         
       
     
         [0693]    (0.88 g, 5.53 mmol) 1-(Aminomethyl)cyclopropanamine dihydrochloride (CAS 849149-67-3) was dissolved in THF (10 ml) and CDI (0.9 g, 5.53 mmol, 1.0 equiv.) was added at room temperature. The mixture was stirred for 16 hours at 70° C. The reaction mixture was evaporated and extracted with saturated NaHCO 3  solution and five times with dichloromethane. The organic layers were dried over Na 2 SO 4  and evaporated to dryness. The desired 4,6-diaza-spiro[2.4]heptan-5-one (0.52 g, 50% purity, 42% yield) was obtained as a white solid, MS: m/e=113.0 (M+H + ) and was used without further purification in the next step. 
       Step 3: 6-(5-Phenylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one 
       [0694]    
       
                 
         
             
             
         
       
     
         [0695]    The title compound was obtained as a yellow solid, MS: m/e=290.1 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-phenylethynyl-pyridine (Example 96, step 1) and 4,6-diaza-spiro[2.4]heptan-5-one (Example 96, step 2). 
       Step 4: 4-Methyl-6-(5-phenylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one 
       [0696]    
       
                 
         
             
             
         
       
     
         [0697]    The title compound was obtained as a white solid, MS: m/e=304.1 (M+H + ), using chemistry similar to that described in Example 16 from 6-(5-phenylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one (Example 96, step 3) and iodomethane. 
       Example 97 
     3,3-Dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-azetidin-2-one 
       [0698]    
       
                 
         
             
             
         
       
     
       Step 1: N-(5-Bromo-pyridin-2-yl)-3-chloro-2,2-dimethyl-propionamide 
       [0699]    
       
                 
         
             
             
         
       
     
         [0700]    To a solution of 2-amino-5-bromopyridine (100 mg, 0.454 mmol) in dichloromethane (6 ml) were added triethylamine (0.19 ml, 1.364 mmol, 3 equiv.) and 3-chloro-2,2-dimethyl-propionyl chloride (CAS 4300-97-4) (140 mg, 0.909 mmol, 2 equiv.) at 0-5° C. The mixture was stirred for 16 hours at room temperature. The reaction mixture was evaporated and the crude product was purified by flash chromatography on silica gel column and eluting with an ethyl acetate:heptane gradient 5:95 to 10:90. The desired N-(5-bromo-pyridin-2-yl)-3-chloro-2,2-dimethyl-propionamide (154 mg, 74% yield) was obtained as a white solid. 
       Step 2: 1-(5-Bromo-pyridin-2-yl)-3,3-dimethyl-azetidin-2-one 
       [0701]    
       
                 
         
             
             
         
       
     
         [0702]    (250 mg, 0.738 mmol) N-(5-Bromo-pyridin-2-yl)-3-chloro-2,2-dimethyl-propionamide (Example 97, step 1) dissolved in DMF (3 ml) was added at room temperature to a solution of NaH (29.5 mg, 0.738 mmol, 1 equiv.) in 5 ml DMF. The mixture was stirred for 3 hours at 70° C. The reaction mixture was evaporated and the crude product was purified by flash chromatography on silica gel column and eluting with an ethyl acetate:heptane gradient 10:90 to 15:85. The desired 1-(5-bromo-pyridin-2-yl)-3,3-dimethyl-azetidin-2-one (160 mg, 72% yield) was obtained as a white solid. 
       Step 3: 3,3-Dimethyl-1-(5-phenylethynyl-pyridin-2-yl)-azetidin-2-one 
       [0703]    
       
                 
         
             
             
         
       
     
         [0704]    The title compound was obtained as a brown solid, MS: m/e=277.0 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(5-bromo-pyridin-2-yl)-3,3-dimethyl-azetidin-2-one (Example 97, step 2) and phenylacetylene. 
       Example 98 
     (1RS,5SR)-6-(5-Pyridin-3-ylethynyl-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one 
       [0705]    
       
                 
         
             
             
         
       
     
         [0706]    The title compound was obtained as a brown solid, MS: m/e=290.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (1RS,5SR)-6-(5-bromo-pyridin-2-yl)-6-aza-bicyclo[3.2.0]heptan-7-one (Example 46, step 1) with 3-ethynyl-pyridine. 
       Example 99 
     (3aSR,7aRS)-(3aRS,7RS)-1-Ethyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0707]    
       
                 
         
             
             
         
       
     
       Step 1: (3aSR,7aRS)-(3aRS,7aRS)-1-(5-Iodo-pyridin-2-yl)-3-ethyl-octahydro-benzoimidazol-2-one 
       [0708]    
       
                 
         
             
             
         
       
     
         [0709]    The title compound was obtained as a light yellow solid, MS: m/e=372.2 (M+H + ), using chemistry similar to that described in Example 16 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-octahydro-benzoimidazol-2-one (Example 84, step 2) and iodoethane by stirring the reaction at 60° C. instead of 0-5° C. 
       Step 2: (3aSR,7aRS)-(3aRS,7RS)-1-Ethyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0710]    
       
                 
         
             
             
         
       
     
         [0711]    The title compound was obtained as a brown oil, MS: m/e=346.4 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-3-ethyl-octahydro-benzoimidazol-2-one (Example 99, step 1) and phenylacetylene. 
       Example 100 
     (3aSR,7aRS)-(3aRS,7RS)-1-Ethyl-3-(5-pyridin-3-ylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0712]    
       
                 
         
             
             
         
       
     
         [0713]    The title compound was obtained as a brown solid, MS: m/e=347.8 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-3-ethyl-octahydro-benzoimidazol-2-one (Example 99, step 1) and 3-ethynyl-pyridine. 
       Example 101 
     (3aSR,7aRS)-(3aRS,7RS)-1-Isopropyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0714]    
       
                 
         
             
             
         
       
     
       Step 1: (3aSR,7aRS)-(3aRS,7aRS)-1-(5-Iodo-pyridin-2-yl)-3-isopropyl-octahydro-benzoimidazol-2-one 
       [0715]    
       
                 
         
             
             
         
       
     
         [0716]    The title compound was obtained as a white solid using chemistry similar to that described in Example 16 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-octahydro-benzoimidazol-2-one (Example 84, step 2) and isopropyl iodide by stirring the reaction at 60° C. instead of 0-5° C. 
       Step 2: (3aSR,7aRS)-(3aRS,7RS)-1-Isopropyl-3-(5-phenylethynyl-pyridin-2-yl)-octahydro-benzoimidazol-2-one 
       [0717]    
       
                 
         
             
             
         
       
     
         [0718]    The title compound was obtained as a brown oil, MS: m/e=360.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (3aSR,7aRS)-(3aRS,7aRS)-1-(5-iodo-pyridin-2-yl)-3-isopropyl-octahydro-benzoimidazol-2-one (Example 101, step 1) and phenylacetylene. 
       Example 102 
     (4aRS,7aSR)-3-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one 
       [0719]    
       
                 
         
             
             
         
       
     
       Step 1: (4aRS,7aSR)-3-(5-Iodo-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one 
       [0720]    
       
                 
         
             
             
         
       
     
         [0721]    The title compound was obtained as a white solid, MS: m/e=345.0 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and (1SR,2RS)-2-aminomethyl-cyclopentanol (CAS 40482-02-8) by using triphosgene and triethylamine in THF for 12 hours at room temperature instead of the conditions used in Example 1, step 2. 
       Step 2: (4aRS,7aSR)-3-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one 
       [0722]    
       
                 
         
             
             
         
       
     
         [0723]    The title compound was obtained as a brown solid, MS: m/e=319.0 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (4aRS,7aSR)-3-(5-iodo-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one (Example 102, step 1) and phenylacetylene. 
       Example 103 
     (4aRS,7aRS)-3-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one 
       [0724]    
       
                 
         
             
             
         
       
     
       Step 1: (4aRS,7aRS)-3-(5-Iodo-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one 
       [0725]    
       
                 
         
             
             
         
       
     
         [0726]    The title compound was obtained as a white solid, MS: m/e=345.0 (M+H + ), using procedures similar to those described in Example 1, step 1 and step 2 from 2-fluoro-5-iodopyridine and (1SR,2SR)-2-aminomethyl-cyclopentanol (CAS 40482-00-6) by using triphosgene and triethylamine in THF for 12 hours at room temperature instead of the conditions used in Example 1, step 2. 
       Step 2: (4aRS,7aRS)-3-(5-Phenylethynyl-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one 
       [0727]    
       
                 
         
             
             
         
       
     
         [0728]    The title compound was obtained as a brown solid, MS: m/e=318.8 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (4aRS,7aRS)-3-(5-iodo-pyridin-2-yl)-hexahydro-cyclopenta[e][1,3]oxazin-2-one (Example 103, step 1) and phenylacetylene. 
       Example 104 
     (RS)-5,6,6-Trimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0729]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-(3-Hydroxy-2,3-dimethyl-butyl)-carbamic acid tert-butyl ester 
       [0730]    
       
                 
         
             
             
         
       
     
         [0731]    The title compound was obtained as a colorless oil, MS: m/e=218.3 (M+H + ), using chemistry similar to that described in Example 95, step 2 from methyl 3-(tert-butoxycarbonylamino)-2-methylpropanoate (CAS 182486-16-4). 
       Step 2: (RS)-5,6,6-Trimethyl-[1,3]oxazinan-2-one 
       [0732]    
       
                 
         
             
             
         
       
     
         [0733]    The title compound was obtained as a yellow solid, MS: m/e=144.0 (M+H + ), using chemistry similar to that described in Example 72, step 2 from (RS)-(3-hydroxy-2,3-dimethyl-butyl)-carbamic acid tert-butyl ester (Example 104, step 1). 
       Step 3: (RS)-5,6,6-Trimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0734]    
       
                 
         
             
             
         
       
     
         [0735]    The title compound was obtained as a yellow oil, MS: m/e=321.1 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-phenylethynyl-pyridine (Example 96, step 1) and (RS)-5,6,6-trimethyl-[1,3]oxazinan-2-one (Example 104, step 2). 
       Example 105 
     (RS)-6-Methoxymethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0736]    
       
                 
         
             
             
         
       
     
         [0737]    The title compound was obtained as a light yellow solid, MS: m/e=323.1 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-phenylethynyl-pyridine (Example 96, step 1) and (RS)-6-methoxymethyl-[1,3]oxazinan-2-one (CAS 39754-63-7). 
       Example 106 
     (3aRS, 6aSR)-1-methyl-3-(5-(phenylethynyl) pyridin-2-yl)hexahydrocyclopenta[d]imidazol-2(1H)-one 
       [0738]    
       
                 
         
             
             
         
       
     
       Step 1: (3aSR, 6aRS)-2-oxo-hexahydro-cyclopentaimidazole-1-carboxylic acid tert-butyl ester 
       [0739]    
       
                 
         
             
             
         
       
     
         [0740]    A solution of (rac)-cis-2-(tert-butoxycarbonylamino)cyclopentanecarboxylic acid (2.28 g, 9.98 mmol) and N-methylmorpholine (1.1 g, 1.21 ml, 11.0 mmol, 1.1 equiv.) in 28 ml of dichloroethane was stirred at r.t. for 10 min. Then diphenylphosphoricacid azide (3.02 g, 2.37 ml, 11.0 mmol, 1.1 equiv.) was added dropwise at room temperature and the colorless solution was stirred for 45 min at room temperature during which the solution turned light yellow. The solution was then warmed to 75° C. and stirred overnight and allowed to cool. After workup with dichloromethane/water, the combined organic phases were evaporated to dryness. The orange solid was triturated with ethyl acetate and filtered to give 1.27 g of a white solid. The mother liquors were concentrated and the cristallized material was again filtered to yield an additional 0.55 g of product. One obtains a total yield of 1.82 g (81%) of the title compound as a crystalline white solid, MS: m/e=227.3 (M+H + ). 
       Step 2: (3aSR, 6aRS)-3-Methyl-2-oxo-hexahydro-cyclopentaimidazole-1-carboxylic acid tert-butyl ester 
       [0741]    
       
                 
         
             
             
         
       
     
         [0742]    To a solution of (3aSR, 6aRS)-2-oxo-hexahydro-cyclopentaimidazole-1-carboxylic acid tert-butyl ester (Example 106, step 1) (1.82 g, 8.04 mmol) in 30 ml of DMF was added a 60% suspension of sodium hydride in mineral oil (386 mg, 9.65 mmol, 1.2 equiv.). The suspension was stirred for 45 minutes at room temperature (gas evolution), then iodomethane (0.604 ml, 9.65 mmol, 1.2 equiv.) was added and the mixture was stirred at room temperature overnight. After concentration in vaccuo and workup with ethyl acetate/water, 2.05 g of a yellow oil were obtained containing mineral-oil drops which was directly used in the next step without further characterisation. 
       Step 3: (3aRS, 6aSR)-1-Methyl-hexahydro-cyclopentaimidazol-2-one 
       [0743]    
       
                 
         
             
             
         
       
     
         [0744]    To a solution of (3aSR, 6aRS)-3-methyl-2-oxo-hexahydro-cyclopentaimidazole-1-carboxylic acid tert-butyl ester (Example 106, step 2) (1.99 g, 8.28 mmol) in 30 ml of dichloromethane was added trifluoroacetic acid (7.55 g, 5.1 ml, 66.3 mmol, 8 equiv.) and the yellow solution was stirred at for 5 h at room temperature. The reaction mixture was quenched by addition of saturated sodium bicarbonate solution and the pH of the aqueous phase was set to 9. After workup with dichloromethane/water, the organic phases were dried, filtered and concentrated in vaccuo to yield 1.07 g of an off-white solid, which was taken up in cold ethyl acetate and filtered to yield the title compound (822 mg, 71%) as a crystalline white solid which was directly used in the next step without further characterisation. 
       Step 4: (3aRS, 6aSR)-1-methyl-3-(5-(phenylethynyl) pyridin-2-yl)hexahydrocyclopenta[d]imidazol-2(1H)-one 
       [0745]    
       
                 
         
             
             
         
       
     
         [0746]    To a suspension of 2-bromo-5-(phenylethynyl)pyridine (Example 96, step 1) (55.0 mg, 0.213 mmol), (3aR,6aS)-1-methylhexahydrocyclopenta[d]imidazol-2(1H)-one (Example 106, step 3) (35.8 mg, 0.256 mmol, 1.2 equiv.), 139 mg cesium carbonate (139 mg, 0.426 mmol, 2 equiv.), and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos) (5 mg, 0.008 mmol, 0.04 equiv.) in 1 ml of toluene was added under argon atmosphere tris(dibenzylideneacetone)dipalladium(0) (Pd 2 (dba) 3 ) (4 mg, 0.0046 mmol, 0.02 equiv.). The mixture was stirred overnight at 70° C. The mixture was directly loaded on a 20 g silicagel column and was eluted with a heptane to 33% ethylacetate in heptane gradient to yield the title compound (49 mg, 73%) as an amorphous light-yellow solid, MS: m/e=318.1 (M+H+). 
       Example 107 
     (RS)-4-tert-Butyl-3-methyl-1-(5-phenylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0747]    
       
                 
         
             
             
         
       
     
         [0748]    The title compound was obtained as a light yellow solid, MS: m/e=334.1 (M+H + ), using procedures similar to those described in Example 106 starting from (rac)-2-(tert-butoxycarbonylamino-methyl)-3,3-dimethyl-butyric acid instead of (rac)-cis-2-(tert-butoxycarbonylamino)cyclopentanecarboxylic acid. 
       Examples 108 
     1-[5-(3-Fluoro-phenylethynyl)-3-methyl-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0749]    
       
                 
         
             
             
         
       
     
       Step 1: 4,4-Dimethyl-1-(3-methyl-5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one 
       [0750]    
       
                 
         
             
             
         
       
     
         [0751]    The title compound was obtained as a yellow solid, MS: m/e=302.1 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-3-methyl-5-trimethylsilanylethynyl-pyridine (Example 41, step 1) and 4,4-dimethyl-imidazolidin-2-one (CAS 24572-33-6). 
       Step 2: 1-[5-(3-Fluoro-phenylethynyl)-3-methyl-pyridin-2-yl]-4,4-dimethyl-imidazolidin-2-one 
       [0752]    
       
                 
         
             
             
         
       
     
         [0753]    The title compound was obtained as a light yellow solid, MS: m/e=324.4 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4,4-dimethyl-1-(3-methyl-5-trimethylsilanylethynyl-pyridin-2-yl)-imidazolidin-2-one (Example 108, step 1) and 1-fluoro-3-iodobenzene. 
       Step 3: 1-[5-(3-Fluoro-phenylethynyl)-3-methyl-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0754]    
       
                 
         
             
             
         
       
     
         [0755]    The title compound was obtained as a light yellow solid, MS: m/e=338.3 (M+H + ), using chemistry similar to that described in Example 16 from 1-[5-(3-fluoro-phenylethynyl)-3-methyl-pyridin-2-yl]-4,4-dimethyl-imidazolidin-2-one (Example 108, step 2) and iodomethane. 
       Example 109 
     (3aSR,6aRS)-1-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-3-methyl-hexahydro-cyclopenta-imidazol-2-one 
       [0756]    
       
                 
         
             
             
         
       
     
       Step 1: (3aRS,6aSR)-1-Methyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-hexahydro-cyclopenta-imidazol-2-one 
       [0757]    
       
                 
         
             
             
         
       
     
         [0758]    The title compound, an off-white solid, MS: m/e=314.1 (M+H + ), was prepared in accordance with the general method of example 106, step 4 starting from 2-bromo-5-((trimethylsilyl)ethynyl)-pyridine (Example 37, step 1) and (3aRS,6aSR)-1-methylhexahydrocyclopenta[d]imidazol-2(1H)-one (Example 106, step 3). 
       Step 2: (3aSR,6aRS)-1-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-3-methyl-hexahydro-cyclopenta-imidazol-2-one 
       [0759]    
       
                 
         
             
             
         
       
     
         [0760]    The title compound, a light yellow oil, MS: m/e=336.2 (M+H + ), was prepared in accordance with the general method of Example 37, step 3 starting from (3aRS,6aSR)-1-methyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-hexahydro-cyclopenta-imidazol-2-one (Example 109, step 1) and 1-fluoro-3-iodobenzene. 
       Example 110 
     1-[3-Fluoro-5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0761]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(3-Fluoro-5-iodo-pyridin-2-yl)-4,4-dimethyl-imidazolidin-2-one 
       [0762]    
       
                 
         
             
             
         
       
     
         [0763]    2,3-Difluoro-5-iodopyridine (300 mg, 1.24 mmol) was dissolved in 2 ml toluene. (140 mg, 1.24 mmol, 1 equiv.) 4,4-Dimethylimidazolidin-2-one (CAS 24572-33-6) and cesium carbonate (650 mg, 1.99 mmol, 1.6 equiv.) were added and the mixture was heated to 100° C. for 4 hours. The reaction mixture was loaded directly onto a silica gel column and purified by flash chromatography eluting with an ethyl acetate:heptane gradient 0:100 to 100:0. The desired 1-(3-fluoro-5-iodo-pyridin-2-yl)-4,4-dimethyl-imidazolidin-2-one (205 mg, 49% yield) was obtained as a white solid, MS: m/e=336.1 (M+H + ). 
       Step 2: 1-(3-Fluoro-5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one 
       [0764]    
       
                 
         
             
             
         
       
     
         [0765]    The title compound, a yellow oil, MS: m/e=350.0 (M+H + ), was prepared in accordance with the general method of Example 16 from 1-(3-fluoro-5-iodo-pyridin-2-yl)-4,4-dimethyl-imidazolidin-2-one (Example 110, step 1) and iodomethane. 
       Step 3: 1-[3-Fluoro-5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0766]    
       
                 
         
             
             
         
       
     
         [0767]    The title compound was obtained as a light yellow solid, MS: m/e=342.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(3-fluoro-5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 110, step 2) and 1-ethynyl-4-fluorobenzene. 
       Example 111 
     1-[3-Fluoro-5-(3-fluoro-phenylethynyl)-pyridin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0768]    
       
                 
         
             
             
         
       
     
         [0769]    The title compound was obtained as a light yellow solid, MS: m/e=342.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 1-(3-fluoro-5-iodo-pyridin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 110, step 2) and 1-ethynyl-3-fluorobenzene. 
       Example 112 
     6-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-4-methyl-4,6-diaza-spiro[2.4]heptan-5-one 
       [0770]    
       
                 
         
             
             
         
       
     
       Step 1: 4-Methyl-4,6-diaza-spiro[2.4]heptan-5-one 
       [0771]    
       
                 
         
             
             
         
       
     
         [0772]    The title compound was obtained as a white solid using procedures similar to those described in Example 106, step 1 to 3 starting from 1-((tert-butoxycarbonylamino)methyl)cyclopropanecarboxylic acid instead of (rac)-cis-2-(tert-butoxycarbonylamino)cyclopentanecarboxylic acid. 
       Step 2: 4-Methyl-6-(5-trimethylsilanylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one 
       [0773]    
       
                 
         
             
             
         
       
     
         [0774]    The title compound was obtained as a white solid, MS: m/e=300.2 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and 4-methyl-4,6-diaza-spiro[2.4]heptan-5-one (Example 112, step 1). 
       Step 3: 6-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-4-methyl-4,6-diaza-spiro[2.4]heptan-5-one 
       [0775]    
       
                 
         
             
             
         
       
     
         [0776]    The title compound was obtained as a light yellow solid, MS: m/e=322.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4-methyl-6-(5-trimethylsilanylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one (Example 112, step 2) and 1-fluoro-4-iodobenzene. 
       Example 113 
     6-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-4-methyl-4,6-diaza-spiro[2.4]heptan-5-one 
       [0777]    
       
                 
         
             
             
         
       
     
         [0778]    The title compound was obtained as a light brown solid, MS: m/e=322.2 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 4-methyl-6-(5-trimethylsilanylethynyl-pyridin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one (Example 112, step 2) and 1-fluoro-3-iodobenzene. 
       Example 114 
     (RS)-5-Methoxy-6,6-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0779]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-3-Benzyloxycarbonylamino-2-methoxy-propionic acid methyl ester 
       [0780]    
       
                 
         
             
             
         
       
     
         [0781]    The title compound was obtained using chemistry similar to that described in Example 16 starting from (RS)-3-benzyloxycarbonylamino-2-hydroxy-propionic acid methyl ester, which was directly used in the next step without further characterisation. 
       Step 2: (RS)-5-Methoxy-6,6-dimethyl-[1,3]oxazinan-2-one 
       [0782]    
       
                 
         
             
             
         
       
     
         [0783]    The title compound was obtained as a light yellow oil, MS: m/e=160.2 (M+H + ), using procedures similar to those described in Example 95, step 2 and Example 72, step 2 from (RS)-3-benzyloxycarbonylamino-2-methoxy-propionic acid methyl ester (Example 114, step 1). 
       Step 3: (RS)-5-Methoxy-6,6-dimethyl-3-(5-phenylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [0784]    
       
                 
         
             
             
         
       
     
         [0785]    The title compound was obtained as a light yellow oil, MS: m/e=337.3 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-phenylethynyl-pyridine (Example 96, step 1) and (RS)-5-methoxy-6,6-dimethyl-[1,3]oxazinan-2-one (Example 114, step 2). 
       Example 115 
     4,4-Dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one 
       [0786]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Methanesulfonyl-5-phenylethynyl-pyrimidine 
       [0787]    
       
                 
         
             
             
         
       
     
         [0788]    Bis-(triphenylphosphine)-palladium(II)dichloride (1.48 g, 2.11 mmol, 0.05 equiv.) was dissolved in 200 ml THF. (10 g, 42.2 mmol) 5-Bromo-2-(methylsulfonyl)pyrimidine and phenylacetylene (9.26 ml, 84.4 mmol, 2 equiv.) were added at room temperature. Triethylamine (17.6 ml, 127 mmol, 3 equiv.), triphenylphosphine (330 mg, 1.3 mmol, 0.03 equiv.) and copper(I)iodide (80 mg, 420 μmol, 0.01 equiv.) were added and the mixture was stirred for 4 hours at 65° C. The reaction mixture was cooled and extracted with saturated NaHCO 3  solution and two times with EtOAc. The organic layers were extracted with water, dried over sodium sulfate and evaporated to dryness. The crude product was purified by flash chromatography on a silica gel column and eluting with an ethyl acetate:heptane gradient 0:100 to 100:0. The desired 2-methanesulfonyl-5-phenylethynyl-pyrimidine (6.2 g, 57% yield) was obtained as a yellow solid, MS: m/e=259.1 (M+H + ). 
       Step 2: 4,4-Dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one 
       [0789]    
       
                 
         
             
             
         
       
     
         [0790]    (100 mg, 0.39 mmol) 2-Methanesulfonyl-5-phenylethynyl-pyrimidine (Example 115, step 1) was dissolved in 1 ml dioxane. 4,4-Dimethylpyrrolidin-2-one (53 mg, 465 μmol, 1.2 equiv.) and cesium carbonate (190 mg, 580 μmol, 1.5 equiv.) were added at room temperature. The mixture was stirred for 4 hours at 100° C. The reaction mixture was cooled, evaporated and extracted with saturated NaHCO 3  solution and two times with a small volume of dichloromethane. The crude product was purified by flash chromatography by directly loading the dichloromethane layers onto a silica gel column and eluting with an ethyl acetate:heptane gradient 0:100 to 100:0. The desired 4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one (32 mg, 28% yield) was obtained as a light yellow solid, MS: m/e=292.1 (M+H + ). 
       Example 116 
     5,5-Dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-piperidin-2-one 
       [0791]    
       
                 
         
             
             
         
       
     
         [0792]    The title compound was obtained as a brown oil, MS: m/e=306.2 (M+H + ), using chemistry similar to that described in Example 115, step 2 from 2-methanesulfonyl-5-phenylethynyl-pyrimidine (Example 115, step 1) and 5,5-dimethylpiperidin-2-one (CAS 4007-79-8). 
       Example 117 
     2-(5-Phenylethynyl-pyrimidin-2-yl)-2-aza-spiro[4.4]nonan-3-one 
       [0793]    
       
                 
         
             
             
         
       
     
         [0794]    The title compound was obtained as a light yellow solid, MS: m/e=318.2 (M+H + ), using chemistry similar to that described in Example 115, step 2 from 2-methanesulfonyl-5-phenylethynyl-pyrimidine (Example 115, step 1) and 2-aza-spiro[4.4]nonan-3-one (CAS 75751-72-3). 
       Example 118 
     1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0795]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Bromo-pyrimidin-2-yl)-4,4-dimethyl-pyrrolidin-2-one 
       [0796]    
       
                 
         
             
             
         
       
     
         [0797]    The title compound was obtained as a light yellow solid, MS: m/e=270.1/272.2 (M+H + ), using chemistry similar to that described in Example 115, step 2 from 5-bromo-2-fluoropyrimidine and 4,4-dimethylpyrrolidin-2-one. 
       Step 2: 1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0798]    
       
                 
         
             
             
         
       
     
         [0799]    The title compound was obtained as a light yellow solid, MS: m/e=310.2 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-bromo-pyrimidin-2-yl)-4,4-dimethyl-pyrrolidin-2-one (Example 118, step 1) and 1-ethynyl-3-fluoro-benzene. 
       Example 119 
     1-[5-(3-Chloro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0800]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Chloro-5-(3-chloro-phenylethynyl)-pyrimidine 
       [0801]    
       
                 
         
             
             
         
       
     
         [0802]    The title compound was obtained as a light brown solid, MS: m/e=248/250 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 2-chloro-5-iodopyrimidine and 1-chloro-3-ethynyl-benzene. 
       Step 2: 1-[5-(3-Chloro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0803]    
       
                 
         
             
             
         
       
     
         [0804]    The title compound was obtained as a light yellow solid, MS: m/e=326.3/328.3 (M+H + ), using chemistry similar to that described in Example 115, step 2 from 2-chloro-5-(3-chloro-phenylethynyl)-pyrimidine (Example 119, step 1) and 4,4-dimethylpyrrolidin-2-one. 
       Example 120 
       [0805]    1-[5-(4-Fluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
         [0000]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Bromo-5-trimethylsilanylethynyl-pyrimidine 
       [0806]    
       
                 
         
             
             
         
       
     
         [0807]    2-Bromo-5-iodopyrimidine (1.2 g, 4.2 mmol) was dissolved under nitrogen in 25 ml THF. Bis-(triphenylphosphine)-palladium(II)dichloride (300 mg, 420 μmol, 0.1 equiv.), ethynyltrimethylsilane (540 mg, 0.77 ml, 5.48 mmol, 1.3 equiv.), triethylamine (0.85 g, 1.17 ml, 8.4 mmol, 2 equiv.) and copper(I)iodide (40 mg, 210 μmol, 0.05 equiv.) were added and the mixture was stirred for 4 hours at 50° C. The reaction mixture was cooled and evaporated to dryness. The crude product was purified by flash chromatography on silica gel, eluting with an ethyl acetate:heptane gradient 0:100 to 40:60. The desired 2-bromo-5-trimethylsilanylethynyl-pyrimidine (0.75 g, 70% yield) was obtained as a yellow solid, MS: m/e=255/257 (M+H + ). 
       Step 2: 4,4-Dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one 
       [0808]    
       
                 
         
             
             
         
       
     
         [0809]    (200 mg, 0.78 mmol) 2-Bromo-5-trimethylsilanylethynyl-pyrimidine (Example 120, step 1) was dissolved in toluene (7 ml) and 4,4-dimethylpyrrolidin-2-one (89 mg, 0.78 mmol, 1.0 equiv.), cesium carbonate (410 mg, 1.25 mmol, 1.6 equiv.), xantphos (CAS 161265-03-8) (18 mg, 0.03 mmol, 0.04 equiv.) and Pd 2 (dba) 3  (14 mg, 0.01 mmol, 0.02 equiv.) were added under nitrogen. The mixture was stirred for 2 hours at 90° C. The crude product was purified by flash chromatography by directly loading the toluene mixture onto a silica gel column and eluting with an ethyl acetate:heptane gradient 0:100 to 100:0. The desired 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one (164 mg, 73% yield) was obtained as a light red solid, MS: m/e=288.1 (M+H + ). 
       Step 3: 1-[5-(4-Fluoro-phenylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0810]    
       
                 
         
             
             
         
       
     
         [0811]    4,4-Dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one (Example 120, step 2) (30 mg, 0.1 mmol) was dissolved in DMF (1 ml). 1-Fluoro-4-iodobenzene (32 mg, 0.14 mmol, 1.4 equiv.), Et 3 N (43 μl, 0.31 mmol, 3 equiv.), Bis-(triphenylphosphine)-1-palladium(II)dichloride (4 mg, 5.2 μmol, 0.05 equiv.) and copper(I)iodide (0.6 mg, 3.1 μmol, 0.03 equiv.) were added under nitrogen and the mixture was heated to 70° C. TBAF 1M in THF (115 μl, 0.115 mmol, 1.1 equiv.) was added dropwise in 20 minutes at 70° C. The reaction mixture was stirred for 30 minutes at 70° C. and evaporated with isolute to dryness. The crude product was purified by flash chromatography with a 20 g silica gel column and eluting with heptane:ethyl acetate 100:0-&gt;0:100. The desired 1-[5-(4-fluoro-phenylethynyl)-pyridin-2-yl]-4,4-dimethyl-pyrrolidin-2-one (24 mg, 73% yield) was obtained as a white solid, MS: m/e=310.1 (M+H + ). 
       Example 121 
     1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-pyrrolidin-2-one 
       [0812]    
       
                 
         
             
             
         
       
     
         [0813]    The title compound was obtained as a white solid, MS: m/e=328.2 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one (Example 120, step 2) and 1,4-difluoro-2-iodobenzene. 
       Example 122 
     3,4,4-Trimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-imidazolidin-2-one 
       [0814]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Iodo-pyrimidin-2-yl)-4,4-dimethyl-imidazolidin-2-one 
       [0815]    
       
                 
         
             
             
         
       
     
         [0816]    The title compound was obtained as a light yellow solid, MS: m/e=319 (M+H + ), using chemistry similar to that described in Example 115, step 2 from 2-chloro-5-iodopyrimidine and 4,4-dimethyl-imidazolidin-2-one (CAS 24572-33-6). 
       Step 2: 1-(5-Iodo-pyrimidin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one 
       [0817]    
       
                 
         
             
             
         
       
     
         [0818]    (55 mg, 173 μmol) 1-(5-Iodo-pyrimidin-2-yl)-4,4-dimethyl-imidazolidin-2-one (Example 122, step 1) was dissolved in DMF (1 ml) and cooled to 0-5° C. NaH (55%) (9 mg, 225 μmol, 1.3 equiv.) was added and the mixture was stirred for 30 min at 0-5° C. Iodomethane (13 μl, 200 μmol, 1.2 equiv.) was added and the mixture was stirred for 30 min without cooling bath. The reaction mixture was treated with sat. NaHCO 3  solution and extracted twice with a small volume of CH 2 Cl 2 . The organic layers were loaded directly to silica gel column and the crude material was purified by flash chromatography on silica gel (20 gr, ethyl acetate/heptane gradient, 0:100 to 100:0). The desired 1-(5-iodo-pyrimidin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (31 mg, 54% yield) was obtained as a white solid, MS: m/e=333.1 (M+H + ). 
       Step 3: 3,4,4-Trimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-imidazolidin-2-one 
       [0819]    
       
                 
         
             
             
         
       
     
         [0820]    The title compound was obtained as a yellow oil, MS: m/e=307.4 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 122, step 2) and phenylacetylene. 
       Example 123 
     1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0821]    
       
                 
         
             
             
         
       
     
         [0822]    The title compound was obtained as a light yellow solid, MS: m/e=325.2 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 122, step 2) and 1-ethynyl-3-fluoro-benzene. 
       Example 124 
     1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0823]    
       
                 
         
             
             
         
       
     
       Step 1: 4,4-Dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-imidazolidin-2-one 
       [0824]    
       
                 
         
             
             
         
       
     
         [0825]    The title compound was obtained as a light yellow solid, MS: m/e=289.0 (M+H + ), using chemistry similar to that described in Example 120, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyrimidine (Example 120, step 1) and 4,4-dimethyl-imidazolidin-2-one (CAS 24572-33-6). 
       Step 2: 1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-imidazolidin-2-one 
       [0826]    
       
                 
         
             
             
         
       
     
         [0827]    The title compound was obtained as a light brown solid, MS: m/e=329.2 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-imidazolidin-2-one (Example 124, step 1) and 1,4-difluoro-2-iodobenzene. 
       Step 3: 1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0828]    
       
                 
         
             
             
         
       
     
         [0829]    The title compound was obtained as a white solid, MS: m/e=343.1 (M+H + ), using chemistry similar to that described in Example 122, step 2 from 1-[5-(2,5-difluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-imidazolidin-2-one (Example 124, step 2) and iodomethane. 
       Example 125 
       [0830]    1-[5-(4-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
         [0000]    
       
                 
         
             
             
         
       
     
         [0831]    The title compound was obtained as a light brown solid, MS: m/e=325.2 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 122, step 2) and 1-ethynyl-4-fluoro-benzene. 
       Example 126 
     1-[5-(3,4-Difluoro-phenylethynyl)-pyrimidin-2-yl]-3,4,4-trimethyl-imidazolidin-2-one 
       [0832]    
       
                 
         
             
             
         
       
     
         [0833]    The title compound was obtained as a light brown solid, MS: m/e=343.1 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 122, step 2) and 4-ethynyl-1,2-difluoro-benzene. 
       Example 127 
     (RS)-3-Methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one 
       [0834]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-4-Iodo-N-(5-iodo-pyrimidin-2-yl)-2-methoxy-3,3-dimethyl-butyramide 
       [0835]    
       
                 
         
             
             
         
       
     
         [0836]    The title compound was obtained as an orange solid, MS: m/e=476.0 (M+H + ), using chemistry similar to that described in patent WO9637466, page 17, step 2 starting from (RS)-3-methoxy-4,4-dimethyl-dihydro-furan-2-one (CAS 100101-82-4) instead of 3-t-butylcarbamoyloxy-tetrahydrofuran-2-one and by using 2-amino-5-iodopyrimidine instead of 2-amino-4-trifluoromethylpyridine. 
       Step 2: (RS)-1-(5-Iodo-pyrimidin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0837]    
       
                 
         
             
             
         
       
     
         [0838]    The title compound was obtained as a light yellow solid, MS: m/e=348.0 (M+H + ), using chemistry similar to that described in patent WO9637466, page 17, step 3 from (RS)-4-iodo-N-(5-iodo-pyrimidin-2-yl)-2-methoxy-3,3-dimethyl-butyramide (Example 127, step 1). 
       Step 3: (RS)-3-Methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one 
       [0839]    
       
                 
         
             
             
         
       
     
         [0840]    The title compound was obtained as a light yellow solid, MS: m/e=322.2 (M+H + ), using chemistry similar to that described in Example 115, step 1 from (RS)-1-(5-iodo-pyrimidin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 127, step 2) and phenylacetylene. 
       Example 128 
       [0841]    (5R or 5S)-5-Methoxymethyl-3-(5-phenylethynyl-pyrimidin-2-yl)-oxazolidin-2-one 
         [0000]    
       
                 
         
             
             
         
       
     
         [0842]    The title compound, a light yellow solid, MS: m/e=322.3 (M+H + ), was prepared by separation of (RS)-3-methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one (Example 127) using a chiral column (chiralpak AD with heptane:isopropanol 90:10 as solvent). 
       Example 129 
     (5S or 5R)-5-Methoxymethyl-3-(5-phenylethynyl-pyrimidin-2-yl)-oxazolidin-2-one 
       [0843]    
       
                 
         
             
             
         
       
     
         [0844]    The title compound, a light yellow solid, MS: m/e=322.3 (M+H + ), was prepared by separation of (RS)-3-methoxy-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one (Example 127) using a chiral column (chiralpak AD with heptane:isopropanol 90:10 as solvent). 
       Example 130 
     (RS)-1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0845]    
       
                 
         
             
             
         
       
     
         [0846]    The title compound was obtained as a yellow solid, MS: m/e=340.2 (M+H + ), using chemistry similar to that described in Example 115, step 1 from (RS)-1-(5-iodo-pyrimidin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 127, step 2) and 1-ethynyl-3-fluoro-benzene. 
       Example 131 
     (R or S)-1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0847]    
       
                 
         
             
             
         
       
     
         [0848]    The title compound, a white solid, MS: m/e=340.3 (M+H + ), was prepared by separation of (RS)-1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 130) using a chiral column (chiralpak AD with heptane:isopropanol 90:10 as solvent). 
       Example 132 
     (S or R)-1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0849]    
       
                 
         
             
             
         
       
     
         [0850]    The title compound, a white solid, MS: m/e=340.3 (M+H + ), was prepared by separation of (RS)-1-[5-(3-fluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 130) using a chiral column (chiralpak AD with heptane:isopropanol 90:10 as solvent). 
       Example 133 
     (R or S)-1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0851]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-3-Methoxy-4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one 
       [0852]    
       
                 
         
             
             
         
       
     
         [0853]    The title compound was obtained as a light brown solid, MS: m/e=318.1 (M+H + ), using chemistry similar to that described in Example 115, step 1 from (RS)-1-(5-iodo-pyrimidin-2-yl)-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 127, step 2) and ethynyl-trimethyl-silane. 
       Step 2: (RS)-1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0854]    
       
                 
         
             
             
         
       
     
         [0855]    The title compound was obtained as a yellow solid, MS: m/e=358.1 (M+H + ), using chemistry similar to that described in Example 120, step 3 from (RS)-3-methoxy-4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-pyrrolidin-2-one (Example 133, step 1) and 1,4-difluoro-2-iodo-benzene. 
       Step 3: (R or S)-1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one 
       [0856]    
       
                 
         
             
             
         
       
     
         [0857]    The title compound, a white solid, MS: m/e=358.1 (M+H + ), was prepared by separation of (RS)-1-[5-(2,5-difluoro-phenylethynyl)-pyrimidin-2-yl]-3-methoxy-4,4-dimethyl-pyrrolidin-2-one (Example 133, step 2) using a chiral column (Reprosil Chiral NR with heptane:EtOH 70:30 as solvent). 
       Example 134 
     4,4-Dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-piperidin-2-one 
       [0858]    
       
                 
         
             
             
         
       
     
       Step 1: 4,4-Dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-piperidin-2-one 
       [0859]    
       
                 
         
             
             
         
       
     
         [0860]    The title compound was obtained as a light yellow solid, MS: m/e=302.2 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 2 from 2-bromo-5-trimethylsilanylethynyl-pyrimidine (Example 120, step 1) and 4,4-dimethyl-piperidin-2-one (CAS 55047-81-9). 
       Step 2: 4,4-Dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-piperidin-2-one 
       [0861]    
       
                 
         
             
             
         
       
     
         [0862]    The title compound was obtained as a white solid, MS: m/e=306.3 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-piperidin-2-one (Example 134, step 1) and iodobenzene. 
       Example 135 
     1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-piperidin-2-one 
       [0863]    
       
                 
         
             
             
         
       
     
         [0864]    The title compound was obtained as a white solid, MS: m/e=324.2 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-piperidin-2-one (Example 134, step 1) and 1-fluoro-3-iodobenzene. 
       Example 136 
       [0865]    1-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-4,4-dimethyl-piperidin-2-one 
         [0000]    
       
                 
         
             
             
         
       
     
         [0866]    The title compound was obtained as a light yellow solid, MS: m/e=342.3 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-1-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-piperidin-2-one (Example 134, step 1) and 2,5-difluoro-3-iodobenzene. 
       Example 137 
     3,4,4-Trimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0867]    
       
                 
         
             
             
         
       
     
       Step 1: 4,4-Dimethyl-tetrahydro-pyrimidin-2-one 
       [0868]    
       
                 
         
             
             
         
       
     
         [0869]    (3.4 g, 14.3 mmol) (3-Amino-3-methyl-butyl)-carbamic acid tert-butyl ester hydrochloride was dissolved in THF (60 ml) and KOtBu (6.4 g, 57.1 mmol, 4 equiv.) was added. The mixture was stirred for 16 hours at 60° C. and evaporated then with isolute to dryness. The crude product was purified by flash chromatography by directly loading the residue onto a silica gel column and eluting with an ethyl acetate:methanol gradient 100:0 to 70:30. The desired 4,4-dimethyl-tetrahydro-pyrimidin-2-one (1.65 g, 90% yield) was obtained as a light yellow solid, MS: m/e=129.1 (M+H + ). 
       Step 2: 4,4-Dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0870]    
       
                 
         
             
             
         
       
     
         [0871]    The title compound was obtained as a brown solid, MS: m/e=303.2 (M+H + ), using chemistry similar to that described in Example 120, step 2 from 2 from 2-bromo-5-trimethylsilanylethynyl-pyrimidine (Example 120, step 1) and 4,4-dimethyl-tetrahydro-pyrimidin-2-one (Example 137, step 1). 
       Step 3: 4,4-Dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0872]    
       
                 
         
             
             
         
       
     
         [0873]    The title compound was obtained as a yellow solid, MS: m/e=329.2 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one (Example 137, step 2) and iodobenzene. 
       Step 4: 3,4,4-Trimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0874]    
       
                 
         
             
             
         
       
     
         [0875]    The title compound was obtained as a light yellow solid, MS: m/e=321.1 (M+H + ), using chemistry similar to that described in Example 122, step 2 from 4,4-dimethyl-5′-phenylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one (Example 137, step 3) and iodomethane. 
       Example 138 
     5′-(3-Fluoro-phenylethynyl)-3,4,4-trimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0876]    
       
                 
         
             
             
         
       
     
       Step 1: 5′-(3-Fluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0877]    
       
                 
         
             
             
         
       
     
         [0878]    The title compound was obtained as a light brown solid, MS: m/e=325.2 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one (Example 137, step 2) and 1-fluoro-3-iodobenzene. 
       Step 2: 5′-(3-Fluoro-phenylethynyl)-3,4,4-trimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0879]    
       
                 
         
             
             
         
       
     
         [0880]    The title compound was obtained as a yellow oil, MS: m/e=339.2 (M+H + ), using chemistry similar to that described in Example 122, step 2 from 5′-(3-fluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one (Example 138, step 1) and iodomethane. 
       Example 139 
     5′-(2,5-Difluoro-phenylethynyl)-3,4,4-trimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0881]    
       
                 
         
             
             
         
       
     
       Step 1: 5′-(2,5-Difluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0882]    
       
                 
         
             
             
         
       
     
         [0883]    The title compound was obtained as a light brown solid, MS: m/e=343.1 (M+H + ), using chemistry similar to that described in Example 120, step 3 from 4,4-dimethyl-5′-trimethylsilanylethynyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one (Example 137, step 2) and 1,4-difluoro-2-iodobenzene. 
       Step 2: 5′-(2,5-Difluoro-phenylethynyl)-3,4,4-trimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one 
       [0884]    
       
                 
         
             
             
         
       
     
         [0885]    The title compound was obtained as a light yellow solid, MS: m/e=357.2 (M+H + ), using chemistry similar to that described in Example 122, step 2 from 5′-(2,5-difluoro-phenylethynyl)-4,4-dimethyl-3,4,5,6-tetrahydro-[1,2′]bipyrimidinyl-2-one (Example 139, step 1) and iodomethane. 
       Example 140 
     3-Isopropyl-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-imidazolidin-2-one 
       [0886]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Iodo-pyrimidin-2-yl)-3-isopropyl-4,4-dimethyl-imidazolidin-2-one 
       [0887]    
       
                 
         
             
             
         
       
     
         [0888]    The title compound was obtained as a light yellow oil, MS: m/e=361.0 (M+H + ), using chemistry similar to that described in Example 122, step 2 from 1-(5-iodo-pyrimidin-2-yl)-4,4-dimethyl-imidazolidin-2-one (Example 122, step 1) and 2-iodopropane. 
       Step 2: 3-Isopropyl-4,4-dimethyl-1-(5-phenylethynyl-pyrimidin-2-yl)-imidazolidin-2-one 
       [0889]    
       
                 
         
             
             
         
       
     
         [0890]    The title compound was obtained as a light brown solid, MS: m/e=335.2 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3-isopropyl-4,4-dimethyl-imidazolidin-2-one (Example 140, step 1) and phenylacetylene. 
       Example 141 
     1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-isopropyl-4,4-dimethyl-imidazolidin-2-one 
       [0891]    
       
                 
         
             
             
         
       
     
         [0892]    The title compound was obtained as a light brown solid, MS: m/e=353.3 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3-isopropyl-4,4-dimethyl-imidazolidin-2-one (Example 140, step 1) and 1-ethynyl-3-fluorobenzene. 
       Example 142 
       [0893]    1-[5-(4-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-isopropyl-4,4-dimethyl-imidazolidin-2-one 
         [0000]    
       
                 
         
             
             
         
       
     
         [0894]    The title compound was obtained as a light brown solid, MS: m/e=353.3 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3-isopropyl-4,4-dimethyl-imidazolidin-2-one (Example 140, step 1) and 1-ethynyl-4-fluorobenzene. 
       Example 143 
     1-[5-(4-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-ethyl-4,4-dimethyl-imidazolidin-2-one 
       [0895]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Bromo-pyrimidin-2-yl)-4,4-dimethyl-imidazolidin-2-one 
       [0896]    
       
                 
         
             
             
         
       
     
         [0897]    The title compound was obtained as a light brown solid, MS: m/e=271.1/273.1 (M+H + ), using chemistry similar to that described in Example 120, step 2 from 5-bromo-2-iodopyrimidine and 4,4-dimethyl-imidazolidin-2-one (CAS 24572-33-6). 
       Step 2: 1-(5-Bromo-pyrimidin-2-yl)-3-ethyl-4,4-dimethyl-imidazolidin-2-one 
       [0898]    
       
                 
         
             
             
         
       
     
         [0899]    The title compound was obtained as a brown solid, MS: m/e=299.2/301.2 (M+H + ), using chemistry similar to that described in Example 122, step 2 from 1-(5-bromo-pyrimidin-2-yl)-4,4-dimethyl-imidazolidin-2-one (Example 143, step 1) and ethyl iodide. 
       Step 3: 1-(5-Iodo-pyrimidin-2-yl)-3-ethyl-4,4-dimethyl-imidazolidin-2-one 
       [0900]    
       
                 
         
             
             
         
       
     
         [0901]    (350 mg, 1.17 mmol) 1-(5-Bromo-pyrimidin-2-yl)-3-ethyl-4,4-dimethyl-imidazolidin-2-one (Example 143, step 2) was dissolved in dioxane (20 ml) and sodium iodide (700 mg, 4.68 mmol, 4 equiv.), copper(I)iodide (21 mg, 0.234 mmol, 0.2 equiv.) and trans-N,N′-dimethylcyclohexane-1,2-diamine (33 mg, 37 μl, 0.234 mmol, 0.2 equiv.) were added. The mixture was stirred for 16 hours at 100° C. The reaction mixture was cooled and extracted with saturated NaHCO 3  solution and two times ethyl acetate. The organic layers were extracted with brine, dried over sodium sulfate and evaporated to dryness. The desired 1-(5-iodo-pyrimidin-2-yl)-3-ethyl-4,4-dimethyl-imidazolidin-2-one (350 mg, 86% yield) was obtained as a brown solid, MS: m/e=347.0 (M+H + ) and was used without further purification in the next step. 
       Step 4: 1-[5-(4-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-ethyl-4,4-dimethyl-imidazolidin-2-one 
       [0902]    
       
                 
         
             
             
         
       
     
         [0903]    The title compound was obtained as a brown solid, MS: m/e=339.3 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3-ethyl-4,4-dimethyl-imidazolidin-2-one (Example 143, step 3) and 1-ethynyl-4-fluorobenzene. 
       Example 144 
     1-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-3-ethyl-4,4-dimethyl-imidazolidin-2-one 
       [0904]    
       
                 
         
             
             
         
       
     
         [0905]    The title compound was obtained as a light brown solid, MS: m/e=339.3 (M+H + ), using chemistry similar to that described in Example 115, step 1 from 1-(5-iodo-pyrimidin-2-yl)-3-ethyl-4,4-dimethyl-imidazolidin-2-one (Example 143, step 3) and 1-ethynyl-3-fluorobenzene. 
       Example 145 
     (RS)-5,6,6-Trimethyl-3-(5-phenylethynyl-pyrimidin-2-yl)-[1,3]oxazinan-2-one 
       [0906]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-(3-Hydroxy-2,3-dimethyl-butyl)-carbamic acid tert-butyl ester 
       [0907]    
       
                 
         
             
             
         
       
     
         [0908]    The title compound was obtained as a colorless oil, MS: m/e=218.3 (M+H + ), using chemistry similar to that described in Example 95, step 2 from methyl 3-(tert-butoxycarbonylamino)-2-methylpropanoate (CAS 182486-16-4). 
       Step 2: (RS)-5,6,6-Trimethyl-[1,3]oxazinan-2-one 
       [0909]    
       
                 
         
             
             
         
       
     
         [0910]    The title compound was obtained as a yellow solid, MS: m/e=144.0 (M+H + ), using chemistry similar to that described in Example 72, step 2 from (RS)-(3-hydroxy-2,3-dimethyl-butyl)-carbamic acid tert-butyl ester (Example 145, step 1). 
       Step 3: 2-Bromo-5-phenylethynyl-pyrimidine 
       [0911]    
       
                 
         
             
             
         
       
     
         [0912]    The title compound was obtained as a white solid using chemistry similar to that described in Example 120, step 1 from 2-bromo-5-iodopyrimidine and phenylacetylene. 
       Step 4: (RS)-5,6,6-Trimethyl-3-(5-phenylethynyl-pyrimidin-2-yl)-[1,3]oxazinan-2-one 
       [0913]    
       
                 
         
             
             
         
       
     
         [0914]    The title compound was obtained as a yellow solid, MS: m/e=322.2 (M+H + ), using chemistry similar to that described in Example 120, step 2 from 2-bromo-5-phenylethynyl-pyrimidine (Example 145, step 3) and (RS)-5,6,6-trimethyl-[1,3]oxazinan-2-one (Example 145, step 2). 
       Example 146 
     (RS)-3-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-5,6,6-trimethyl-[1,3]oxazinan-2-one 
       [0915]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-5,6,6-Trimethyl-3-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-[1,3]oxazinan-2-one 
       [0916]    
       
                 
         
             
             
         
       
     
         [0917]    The title compound was obtained as a brown solid, MS: m/e=318.1 (M+H + ), using chemistry similar to that described in Example 120, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyrimidine (Example 120, step 1) and (RS)-5,6,6-trimethyl-[1,3]oxazinan-2-one (Example 145, step 2). 
       Step 2: (RS)-3-[5-(2,5-Difluoro-phenylethynyl)-pyrimidin-2-yl]-5,6,6-trimethyl-[1,3]oxazinan-2-one 
       [0918]    
       
                 
         
             
             
         
       
     
         [0919]    The title compound was obtained as a white solid, MS: m/e=358.4 (M+H + ), using chemistry similar to that described in Example 120, step 3 from (RS)-5,6,6-trimethyl-3-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-[1,3]oxazinan-2-one (Example 146, step 1) and 1,4-difluoro-2-iodobenzene. 
       Example 147 
     4-Methyl-6-(5-phenylethynyl-pyrimidin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one 
       [0920]    
       
                 
         
             
             
         
       
     
       Step 1: 4-Methyl-4,6-diaza-spiro[2.4]heptan-5-one 
       [0921]    
       
                 
         
             
             
         
       
     
         [0922]    The title compound was obtained as a white solid using procedures similar to those described in Example 106, step 1 to 3 from starting from 1-((tert-butoxycarbonylamino)methyl)cyclopropanecarboxylic acid instead of (rac)-cis-2-(tert-butoxycarbonylamino)cyclopentanecarboxylic acid. 
       Step 2: 4-Methyl-6-(5-phenylethynyl-pyrimidin-2-yl)-4,6-diaza-spiro[2.4]heptan-5-one 
       [0923]    
       
                 
         
             
             
         
       
     
         [0924]    The title compound was obtained as a white solid, MS: m/e=305.3 (M+H + ), using chemistry similar to that described in Example 120, step 2 from 2-bromo-5-phenylethynyl-pyrimidine (Example 145, step 3) and 4-methyl-4,6-diaza-spiro[2.4]heptan-5-one (Example 147, step 1). 
       Example 148 
     (RS)-3-[5-(3-Fluoro-phenylethynyl)-pyrimidin-2-yl]-5,6,6-trimethyl-[1,3]oxazinan-2-one 
       [0925]    
       
                 
         
             
             
         
       
     
         [0926]    The title compound was obtained as a yellow solid, MS: m/e=340.1 (M+H + ), using chemistry similar to that described in Example 120, step 3 from (RS)-5,6,6-trimethyl-3-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-[1,3]oxazinan-2-one (Example 146, step 1) and 1-fluoro-3-iodobenzene. 
       Example 149 
     (RS)-3-[5-(4-Fluoro-phenylethynyl)-pyrimidin-2-yl]-5,6,6-trimethyl-[1,3]oxazinan-2-one 
       [0927]    
       
                 
         
             
             
         
       
     
         [0928]    The title compound was obtained as a yellow solid, MS: m/e=340.1 (M+H + ), using chemistry similar to that described in Example 120, step 3 from (RS)-5,6,6-trimethyl-3-(5-trimethylsilanylethynyl-pyrimidin-2-yl)-[1,3]oxazinan-2-one (Example 146, step 1) and 1-fluoro-4-iodobenzene. 
       Example 150 
     4,4-Dimethyl-1-(6-(phenylethynyl)pyridazin-3-yl)pyrrolidin-2-one 
       [0929]    
       
                 
         
             
             
         
       
     
         [0930]    To a solution of 3-chloro-6-(phenylethynyl)pyridazine (CAS 77778-15-5) (180 mg, 839 mmol) and 4,4-dimethylpyrrolidin-2-one (CAS 66899-02-3) (142 mg, 1.26 mmol, 1.5 equiv.) in 2 ml of DMF were added cesium carbonate (546 mg, 1.68 mmol, 2 equiv.). The suspension was heated 16 hours at 120° C. and then allowed to cool to room temperature. Ethyl acetate (10 ml) were added and the unsoluble salts were filtered off. After concentration in vaccuo, the residue was dissolved in 10 ml of ethyl acetate. Silicagel (4 g) were added and the suspension was evaporated to dryness. The silicagel with the adsorbed crude mixture was loaded onto a 20 g silicagel flash chromatography column and eluted three min. with heptane followed by a heptane to 45% ethyl acetate/heptane gradient over 25 min to yield 36 mg (15% yield) of the title compound as a cristalline yellow solid, MS: m/e=292.3 (M+H + ). 
       Example 151 
     4,4-Dimethyl-1-(6-(phenylethynyl)pyridazin-3-yl)piperidin-2-one 
       [0931]    
       
                 
         
             
             
         
       
     
       Step 1: 3-Iodo-6-(phenylethynyl)pyridazine 
       [0932]    
       
                 
         
             
             
         
       
     
         [0933]    To a solution of 100 mg (0.466 mmol) of 3-chloro-6-(phenylethynyl)pyridazine in 5 ml of acetonitrile were added sodium iodide (209 mg, 1.4 mmol, 3 equiv.), acetic acid (56 mg, 53.3 ml, 0.93 mmol, 2 equiv.), and 95% sulfuric acid (4.6 mg, 2.5 ml, 0.47 mmol, 1 equiv.). The orange solution was stirred for 8 hours at 70° C. and then left to cool overnight. After standard workup with ethyl acetate/water, the residue was adsorbed onto 4 g of silicagel and purified by flash chromatography over a 20 g silicagel column over a heptane to 50% ethyl acetate in heptane gradient to yield 82 mg (58% yield) of the title compound as a crystalline light yellow solid, MS: m/e=307.1 (M+H + ). 
       Step 2: 4,4-Dimethyl-1-(6-(phenylethynyl)pyridazin-3-yl)piperidin-2-one 
       [0934]    
       
                 
         
             
             
         
       
     
         [0935]    To a well stirred suspension of 3-iodo-6-(phenylethynyl)pyridazine (Example 151, step 1) (80 mg, 261 μmol), 4,4-dimethylpiperidin-2-one (66.5 mg, 314 μmol, 1.2 equiv.) and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos) (6.05 mg, 10.5 μmol, 0.04 equiv.) in 2 ml of toluene were added under argon atmosphere tris(dibenzylideneacetone)dipalladium(0) (Pd 2 (dba) 3 ), (4.79 mg, 5.23 μmol, 0.02 equiv.) and the mixture was stirred for 4 hours at 100° C. The crude mixture was directly purified by flash chromatography over a 20 g silicagel column using a heptane to 50% ethyl acetate in heptane gradient, and yielded 18 mg (23% yield) of the title compound as a white solid, MS: m/e=306.2 (M+H + ). 
       Example 152 
     5,5-Dimethyl-3-(6-(phenylethynyl)pyridazin-3-yl)oxazolidin-2-one 
       [0936]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Methyl-1-(6-phenylethynyl-pyridazin-3-ylamino)-propan-2-ol 
       [0937]    
       
                 
         
             
             
         
       
     
         [0938]    A solution of 3-chloro-6-(phenylethynyl)pyridazine (CAS 77778-15-5) (300 mg, 1.4 mmol) and 1-amino-2-methylpropan-2-ol (137 mg, 147 μl, 1.54 mmol, 1.1 equiv.) in 3 ml of pyridine was heated 20 hours at 120° C. in a sealed tube. The solvent was removed in vaccuo. The residue was taken up in ethyl acetate/methanol, adsorbed onto 4 g of silica and purified on a 20 g flash chromatography column using a heptane to ethyl acetate gradient to yield 90 mg (24% yield) of the title compound as a crystalline light yellow solid, MS: m/e=268.2 (M+H + ). 
       Step 2: 5,5-Dimethyl-3-(6-(phenylethynyl)pyridazin-3-yl)oxazolidin-2-one 
       [0939]    
       
                 
         
             
             
         
       
     
         [0940]    A solution of 2-methyl-1-(6-(phenylethynyl)pyridazin-3-ylamino)propan-2-ol (Example 152, step 1) (90 mg, 337 μmol) and triethylamine (102 mg, 141 μl, 1.01 mmol, 3 equiv.) in 4 ml of THF was cooled to 0-5° C. and then triphosgene (99.9 mg, 337 μmol, 1 equiv.) was added and the reaction was stirred for 1 hour at 0-5° C. The mixture was quenched with 5 ml of 5% sodium bicarbonate solution and worked up with ethyl acetate/water. The crude material was adsorbed onto silicagel and purified by flash chromatography over a heptane to 50% ethyl acetate in heptane gradient to yield the title compound (51 mg, 52% yield) as a crystalline light yellow solid, MS: m/e=294.2 (M+H + ). 
       Example 153 
     6,6-Dimethyl-3-(6-(phenylethynyl)pyridazin-3-yl)-1,3-oxazinan-2-one 
       [0941]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Methyl-4-(6-phenylethynyl-pyridazin-3-ylamino)-butan-2-ol 
       [0942]    
       
                 
         
             
             
         
       
     
         [0943]    A solution of 3-chloro-6-(phenylethynyl)pyridazine (CAS 77778-15-5) (125 mg, 0.582 mmol) and 4-amino-2-methylbutan-2-ol hydrochloride (244 mg, 1.75 mmol, 3 equiv.) and triethylamine (206 mg, 284 ml, 2.04 mmol, 2 equiv.) in 1.25 ml of pyridine was heated 20 hours at 85° C. The solvent was removed in vaccuo. The residue was taken up in ethyl acetate/methanol, adsorbed onto 4 g of silica and purified on a 20 g flash chromatography column using a heptane/ethyl acetate 85:15 to 15:85 gradient to yield 44 mg (27% yield) of the title compound as a crystalline white solid, MS: m/e=282.2 (M+H + ). 
       Step 2: 6,6-Dimethyl-3-(6-(phenylethynyl)pyridazin-3-yl)-1,3-oxazinan-2-one 
       [0944]    
       
                 
         
             
             
         
       
     
         [0945]    The title compound, a crystalline light yellow solid, MS: m/e=308.3 (M+H + ), was prepared in accordance with the general method of Example 152, step 2 starting from 2-methyl-4-(6-phenylethynyl-pyridazin-3-ylamino)-butan-2-ol (Example 153, step 1) and triphosgene. 
       Example 154 
     3,4,4-Trimethyl-1-(6-(m-tolylethynyl)pyridazin-3-yl)imidazolidin-2-one 
       [0946]    
       
                 
         
             
             
         
       
     
       Step 1: N-1-(6-Iodo-pyridazin-3-yl)-2-methyl-propane-1,2-diamine 
       [0947]    
       
                 
         
             
             
         
       
     
         [0948]    A suspension of 3-chloro-6-iodo-pyridazine (CAS 135034-10-5) (500 mg, 2.08 mmol) and 2-methylpropane-1,2-diamine (220 mg, 262 μl, 2.5 mmol, 1.2 equiv.) in 4 ml of pyridine was heated 16 hours at 100° C. The solvent was removed in vaccuo. The crude material (508 mg) was directly used in the next step. 
       Step 2: 1-(6-Chloro-pyridazin-3-yl)-4,4-dimethyl-imidazolidin-2-one 
       [0949]    
       
                 
         
             
             
         
       
     
         [0950]    To a solution of crude N-1-(6-iodopyridazin-3-yl)-2-methylpropane-1,2-diamine (Example 154, step 1) (580 mg, 1.99 mmol) and pyridine (346 mg, 353 μl, 4.37 mmol, 2.2 equiv.) in 5 ml of dichloromethane were added (1.96 g, 2.1 ml, 3.97 mmol, 2 equiv.) of a 20% solution of phosgene in toluene dropwise at 0-2° C. over a period of 10 min. After stirring for 2 hours at 0-4° C., the reaction was allowed to warm up to room temperature overnight. The mixture was quenched with 5 ml of 5% sodium bicarbonate solution and worked up with dichloromethane/water. The crude material was adsorbed onto silicagel and purified by flash chromatography using a heptane to 80% ethyl acetate in heptane gradient to yield the title compound (where the iodine was completely exchanged for chlorine) (140 mg, 31% yield) as a crystalline white solid, MS: m/e=227.2, 229.4 (M+H + ). 
       Step 3: 1-(6-Chloro-pyridazin-3-yl)-3,4,4-trimethyl-imidazolidin-2-one 
       [0951]    
       
                 
         
             
             
         
       
     
         [0952]    To a solution of 1-(6-chloropyridazin-3-yl)-4,4-dimethylimidazolidin-2-one (Example 154, step 2) (140 mg, 618 μmol) in DMF (3 ml) was added 60% sodium hydride suspension (37.1 mg, 926 μmol, 1.5 equiv.). After stirring at room temperature for 10 min, iodomethane (132 mg, 57.9 μl, 926 μmol, 1.5 equiv.) was added and the suspension was stirred for 1 hour at room temperature. The solvent was removed in vaccuo and the residue was worked up with ethyl acetate/water. The title compound was obtained as a crystalline light brown solid (129 mg, 87% yield), MS: m/e=241.2, 243.4 (M+H + ). 
       Step 4: 1-(6-Iodo-pyridazin-3-yl)-3,4,4-trimethyl-imidazolidin-2-one 
       [0953]    
       
                 
         
             
             
         
       
     
         [0954]    The title compound, crystalline light yellow solid (149 mg, 86%), MS: m/e=333.0 (M+H + ), was prepared from 1-(6-chloro-pyridazin-3-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 154, step 3) in accordance with the general method of Example 151, step 1 by acid catalyzed chlorine-iodine exchange. 
       Step 5: 3,4,4-Trimethyl-1-(6-(m-tolylethynyl)pyridazin-3-yl)imidazolidin-2-one 
       [0955]    
       
                 
         
             
             
         
       
     
         [0956]    To a solution of 1-(6-iodopyridazin-3-yl)-3,4,4-trimethylimidazolidin-2-one (Example 154, step 4) (75 mg, 226 μmol), 1-ethynyl-3-methylbenzene (44.6 mg, 49.5 μl, 384 μmol, 1.7 equiv.), triethylamine (68.5 mg, 94.4 μl, 677 μmol, 3 equiv.), bis(triphenylphosphine)palladium (II) chloride (9.51 mg, 13.5 μmol, 0.06 equiv.) and triphenylphosphine (1.78 mg, 6.77 μmol, 0.03 equiv.) in 2 ml of THF was added under an Argon atmosphere copper (I) iodide (1.29 mg, 6.77 μmol, 0.03 equiv.). The suspension was warmed to 60° C. for 2 hours, taken up in 5 ml of ethyl acetate and adsorbed on 4 g of silica. Purification by flash chromatography on silicagel using a heptane to 50% ethyl acetate/heptane gradient yielded the title compound as a crystalline light yellow solid (18 mg, 25% yield), MS: m/e=321.2 (M+H + ). 
       Example 155 
     1-(6-((3-Chlorophenyl)ethynyl)pyridazin-3-yl)-3,4,4-trimethylimidazolidin-2-one 
       [0957]    
       
                 
         
             
             
         
       
     
         [0958]    The title compound, a crystalline light yellow solid (36 mg, 47% yield), MS: m/e=341.2, 343.3 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(6-iodo-pyridazin-3-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 154, step 4) and 3-chlorophenyl-acetylene. 
       Example 156 
     3,4,4-Trimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)imidazolidin-2-one 
       [0959]    
       
                 
         
             
             
         
       
     
       Step 1: N-1-(5-Iodo-pyrazin-2-yl)-2-methyl-propane-1,2-diamine 
       [0960]    
       
                 
         
             
             
         
       
     
         [0961]    To a solution of 2-bromo-5-iodopyrazine (CAS 622392-04-5) (250 mg, 878 μmol) in 0.7 ml of pyridine, was added 2-methylpropane-1,2-diamine (116 mg, 138 μl, 1.32 mmol, 1.5 equiv.) at room temperature. The colorless solution was stirred for 16 hours at 100° C. The reaction mixture was cooled and concentrated in vacuo. The crude material was used directly in the next step. 
       Step 2: 1-(5-Iodo-pyrazin-2-yl)-4,4-dimethyl-imidazolidin-2-one 
       [0962]    
       
                 
         
             
             
         
       
     
         [0963]    The title compound, an off-white solid (72 mg, 26% yield), was prepared in accordance with the general method of Example 154, step 2; starting from N-1-(5-iodo-pyrazin-2-yl)-2-methyl-propane-1,2-diamine (Example 156, step 1) and cyclisation with phosgene. The crude material was directly used in the next step without further characterization. 
       Step 3: 1-(5-Iodo-pyrazin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one 
       [0964]    
       
                 
         
             
             
         
       
     
         [0965]    The title compound, an off-white solid (77 mg, 99% yield), was prepared in accordance with the general method of Example 154, step 3; by alkylation of 1-(5-iodo-pyrazin-2-yl)-4,4-dimethyl-imidazolidin-2-one (Example 156, step 2) with methyl iodide. The crude material was directly used in the next step without further characterization. 
       Step 4: ′3,4,4-Trimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)imidazolidin-2-one 
       [0966]    
       
                 
         
             
             
         
       
     
         [0967]    The title compound, a crystalline light yellow solid (69 mg, 75% yield), MS: m/e=307.3 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-iodo-pyrazin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 156, step 3) and phenylacetylene. 
       Example 157 
     3,4,4-Trimethyl-1-(5-(pyridin-3-ylethynyl)pyrazin-2-yl)imidazolidin-2-one 
       [0968]    
       
                 
         
             
             
         
       
     
         [0969]    The title compound, a crystalline yellow solid, MS: m/e=308.3 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-iodo-pyrazin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 156, step 3) and 3-pyridylacetylene. 
       Example 158 
     1-(5-((3-Fluorophenyl)ethynyl)pyrazin-2-yl)-3,4,4-trimethylimidazolidin-2-one 
       [0970]    
       
                 
         
             
             
         
       
     
         [0971]    The title compound, a crystalline light yellow solid, MS: m/e=325.2 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-iodo-pyrazin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 156, step 3) and 3-fluorophenylacetylene. 
       Example 159 
     1-(5-((4-Fluorophenyl)ethynyl)pyrazin-2-yl)-3,4,4-trimethylimidazolidin-2-one 
       [0972]    
       
                 
         
             
             
         
       
     
         [0973]    The title compound, a light yellow solid, MS: m/e=325.2 (M+H + ), was prepared in accordance with the general method of example 154, step 5; starting from 1-(5-iodo-pyrazin-2-yl)-3,4,4-trimethyl-imidazolidin-2-one (Example 156, step 3) and 4-fluorophenylacetylene. 
       Example 160 
     4,4-Dimethyl-1-(5-(pyridin-3-ylethynyl)pyrazin-2-yl)pyrrolidin-2-one 
       [0974]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Bromo-pyrazin-2-yl)-4,4-dimethyl-pyrrolidin-2-one 
       [0975]    
       
                 
         
             
             
         
       
     
         [0976]    To a well stirred suspension of 2-bromo-5-iodopyrazine (300 mg, 1.05 mmol), 4,4-dimethylpiperidin-2-one (155 mg, 1.37 mmol, 1.3 equiv.) and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos) (24.4 mg, 0.042 mmol, 0.04 equiv.) in 4 ml of toluene were added under argon atmosphere tris(dibenzylideneacetone)dipalladium(0) (Pd 2 (dba) 3 ), (19.3 mg, 0.021 mmol, 0.02 equiv.) and the mixture was stirred for 5 hours at 100° C. The crude mixture was adsorbed on silicagel and purified by flash chromatography over a 20 g silicagel column using a 2:1 heptane/ethyl acetate mixture as eluant. The title compound (151 mg, 53% yield) was obtained as a white solid, MS: m/e=270.1, 272.1 (M+H + ). 
       Step 2: 4,4-Dimethyl-1-(5-(pyridin-3-ylethynyl)pyrazin-2-yl)pyrrolidin-2-one 
       [0977]    
       
                 
         
             
             
         
       
     
         [0978]    The title compound, a light yellow solid, MS: m/e=310.4 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-bromo-pyrazin-2-yl)-4,4-dimethyl-pyrrolidin-2-one (Example 160, step 1) and 3-fluorophenylacetylene. 
       Example 161 
     1-(5-((3-Fluorophenyl)ethynyl)pyrazin-2-yl)-4,4-dimethylpiperidin-2-one 
       [0979]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Bromo-pyrazin-2-yl)-4,4-dimethyl-piperidin-2-one 
       [0980]    
       
                 
         
             
             
         
       
     
         [0981]    The title compound, an off-white solid, MS: m/e=284.2, 286.0 (M+H + ), was prepared in accordance with the general method of Example 160, step 1; starting from 2-bromo-5-iodopyrazine and 4,4-dimethyl-piperidin-2-one. 
       Step 2: 1-(5-((3-Fluorophenyl)ethynyl)pyrazin-2-yl)-4,4-dimethylpiperidin-2-one 
       [0982]    
       
                 
         
             
             
         
       
     
         [0983]    The title compound, an off-white solid, MS: m/e=324.3 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-bromo-pyrazin-2-yl)-4,4-dimethyl-piperidin-2-one (Example 161, step 1) and 3-fluorophenylacetylene. 
       Example 162 
     4,4-Dimethyl-1-(5-(pyridin-3-ylethynyl)pyrazin-2-yl)piperidin-2-one 
       [0984]    
       
                 
         
             
             
         
       
     
         [0985]    The title compound, an off-white solid, MS: m/e=307.2 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-bromo-pyrazin-2-yl)-4,4-dimethyl-piperidin-2-one (Example 161, step 1) and 3-pyridylacetylene. 
       Example 163 
     4,4-Dimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)piperidin-2-one 
       [0986]    
       
                 
         
             
             
         
       
     
         [0987]    The title compound, a yellow solid, MS: m/e=306.2 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-bromo-pyrazin-2-yl)-4,4-dimethyl-piperidin-2-one (Example 161, step 1) and phenylacetylene. 
       Example 164 
     4,4-Dimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)tetrahydropyrimidin-2(1H)-one 
       [0988]    
       
                 
         
             
             
         
       
     
       Step 1: 1-(5-Bromo-pyrazin-2-yl)-4,4-dimethyl-tetrahydro-pyrimidin-2-one 
       [0989]    
       
                 
         
             
             
         
       
     
         [0990]    The title compound, a light brown solid, MS: m/e=285.0, 287.0 (M+H + ), was prepared in accordance with the general method of Example 160, step 1; starting from 2-bromo-5-iodopyrazine and 4,4-dimethyl-tetrahydro-pyrimidin-2-one (Example 137, step 1). 
       Step 2: 4,4-Dimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)tetrahydropyrimidin-2(1H)-one 
       [0991]    
       
                 
         
             
             
         
       
     
         [0992]    The title compound, a light yellow solid, MS: m/e=307.3 (M+H + ), was prepared in accordance with the general method of example 45, step 5; starting from 1-(5-bromo-pyrazin-2-yl)-4,4-dimethyl-tetrahydro-pyrimidin-2-one (Example 164, step 1) and phenylacetylene. 
       Example 165 
     3,4,4-Trimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)tetrahydropyrimidin-2(1H)-one 
       [0993]    
       
                 
         
             
             
         
       
     
         [0994]    To a solution of 4,4-dimethyl-1-(5-(phenylethynyl)pyrazin-2-yl)tetrahydropyrimidin-2(1H)-one (Example 164, step 2) (30 mg, 0.098 mmol) in 2 ml of DMF was added 60% sodium hydride suspension (4.7 mg, 0.118 mmol, 1.2 equiv.). After stirring at room temperature for 15 min, iodomethane (7.4 ml, 16.7 mg, 0.118 mmol, 1.2 equiv.) was added and the reaction was stirred at room temperature overnight. The reaction mixture was concentrated in vacuo and was worked up with ethyl acetate/water. Flash chromatography over a prepacked 20 g silica column eluting with a heptane to 50% ethyl acetate in heptane gradient yielded the title compound (25.4 mg, 81% yield) as an off-white solid, MS: m/e=321.3 (M+H + ). 
       Example 166 
     1-(5-((3-Fluorophenyl)ethynyl)pyrazin-2-yl)-4,4-dimethyltetrahydropyrimidin-2(1H)-one 
       [0995]    
       
                 
         
             
             
         
       
     
         [0996]    The title compound, an off-white solid, MS: m/e=325.3 (M+H + ), was prepared in accordance with the general method of Example 154, step 5; starting from 1-(5-bromo-pyrazin-2-yl)-4,4-dimethyl-tetrahydro-pyrimidin-2-one (Example 164, step 1) and 3-fluorophenylacetylene. 
       Example 167 
     1-(5-((3-Fluorophenyl)ethynyl)pyrazin-2-yl)-3,4,4-trimethyltetrahydropyrimidin-2(1H)-one 
       [0997]    
       
                 
         
             
             
         
       
     
         [0998]    The title compound, a light yellow solid, MS: m/e=339.1 (M+H + ), was prepared in accordance with the general method of Example 165, by alkylation of 1-(5-((3-fluorophenyl)ethynyl)pyrazin-2-yl)-4,4-dimethyltetrahydropyrimidin-2(1H)-one (Example 166) with methyl iodide. 
       Example 168 
     6,6-Dimethyl-3-(5-(phenylethynyl)pyrazin-2-yl)-1,3-oxazinan-2-one 
       [0999]    
       
                 
         
             
             
         
       
     
       Step 1: 2-Bromo-5-phenylethynyl-pyrazine 
       [1000]    
       
                 
         
             
             
         
       
     
         [1001]    To a solution of 2-bromo-5-iodopyrazine (500 mg, 1.76 mmol), phenylacetylene (224 mg, 241 μL, 2.19 mmol, 1.25 equiv.), triethylamine (533 mg, 734 μL, 5.27 mmol, 3 equiv.), bis(triphenylphosphine)palladium (II) chloride (73.9 mg, 0.105 mmol, 0.06 equiv.) and triphenyl-phosphine (13.8 mg, 0.053 mmol, 0.03 equiv.) in 10 ml of THF was added under an Argon atmosphere copper (I) iodide (10.0 mg, 0.053 mmol, 0.03 equiv.). The suspension was warmed to 60° C. overnight, taken up in 5 ml of ethyl acetate and adsorbed on 4 g of silica. Purification by flash chromatography on silicagel using a 2:1 ethyl acetate/heptane mixture yielded the title compound as a light brown solid (107 mg, 23% yield). The material was directly used in the next step without further characterization. 
       Step 2: 2-Methyl-4-(5-phenylethynyl-pyrazin-2-ylamino)-butan-2-ol 
       [1002]    
       
                 
         
             
             
         
       
     
         [1003]    A solution of 2-bromo-5-(phenylethynyl)pyrazine (Example 168, step 1) (158 mg, 0.061 mmol) and 4-amino-2-methylbutan-2-ol hydrochloride (255 mg, 1.83 mmol, 30 equiv.) and triethylamine (185 mg, 255 μl, 1.83 mmol, 30 equiv.) in 3 ml pyridine was stirred overnight at 85° C. The reaction mixture was concentrated in vaccuo. After workup with dichloromethane/water/brine, and drying over magnesium sulfate, the organic phases were concentrated in vacuo. The crude product was chromatographed over a prepacked 20 g silica column eluting with a 25% to 100% ethyl acetate in heptane gradient which yielded the title compound (87.5 mg, 51% yield) as an off-white solid, MS: m/e=282.2 (M+H + ). 
       Step 3: 6,6-Dimethyl-3-(5-(phenylethynyl)pyrazin-2-yl)-1,3-oxazinan-2-one 
       [1004]    
       
                 
         
             
             
         
       
     
         [1005]    A solution of 2-methyl-4-(5-(phenylethynyl)pyrazin-2-ylamino)butan-2-ol (Example 168, step 2) (84 mg, 0.30 mmol) and triethylamine (91 mg, 125 μl, 0.90 mmol, 3 equiv.) in 2 ml of THF was cooled to 0-5° C. and triphosgene (89 mg, 0.30 mmol, 1 equiv.) was added in portions. The mixture was stirred for 1 hr at 0-5° C. and for 2 hours at room temperature. The reaction mixture was quenched with saturated sodium carbonate solution followed by workup with ethyl acetate/water. The organic layers were combined, dried and concentrated. The crude product was chromatographed over a prepacked 20 g Silica column eluting with a heptane to 50% ethyl acetate in heptane gradient to yield the title compound (66.1 mg, 72% yield) as an off-white solid, MS: m/e=308.3 (M+H + ). 
       Example 169 
     (RS)-3-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-5-methoxy-6,6-dimethyl-[1,3]oxazinan-2-one 
       [1006]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-5-Methoxy-6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one 
       [1007]    
       
                 
         
             
             
         
       
     
         [1008]    The title compound was obtained as a light brown solid, MS: m/e=333.2 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and (RS)-5-methoxy-6,6-dimethyl-[1,3]oxazinan-2-one (Example 114, step 2). 
       Step 2: (RS)-3-[5-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-5-methoxy-6,6-dimethyl-[1,3]oxazinan-2-one 
       [1009]    
       
                 
         
             
             
         
       
     
         [1010]    The title compound was obtained as a yellow oil, MS: m/e=355.0 (M+H + ), using chemistry similar to that described in Example 37, step 3 from (RS)-5-methoxy-6,6-dimethyl-3-(5-trimethylsilanylethynyl-pyridin-2-yl)-[1,3]oxazinan-2-one (Example 169, step 1) and 1-fluoro-3-iodobenzene. 
       Example 170 
     (3aRS,6aSR)-1-Methyl-3-(6-phenylethynyl-pyridazin-3-yl)-hexahydro-cyclopentaimidazol-2-one 
       [1011]    
       
                 
         
             
             
         
       
     
         [1012]    To a solution of (3aRS, 6aSR)-1-methyl-hexahydro-cyclopentaimidazol-2-one (Example 106, step 3) (55 mg, 0.39 mmol, 1.5 equiv.) in 3 ml of DMF was added 60% sodium hydride suspension in mineral oil (17 mg, 0.42 mmol, 1.6 equiv.). The white suspension was stirred for 30 min. at room temperature. Then 3-chloro-6-(phenylethynyl)pyridazine (CAS 77778-15-5) (56 mg, 0.261 mmol) was added and the reaction was stirred for 1 hour at room temperature. After workup with ethyl acetate/water, drying over magnesium sulfate and concentration in vaccuo, the residue was purified by flash chromatography over silica gel eluting with a heptane to 50% ethyl acetate/heptane gradient to yield 40 mg (48% yield) of the title compound as an off-white solid, MS: m/e=319.1 (M+H + ). 
       Example 171 
     (RS)-6-Methyl-4-(5-phenylethynyl-pyridin-2-yl)-morpholin-3-one 
       [1013]    
       
                 
         
             
             
         
       
     
       Step 1: (RS)-4-(5-Iodo-pyridin-2-yl)-6-methyl-morpholin-3-one 
       [1014]    
       
                 
         
             
             
         
       
     
         [1015]    The title compound was obtained as a white solid, MS: m/e=319.0 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2,5-diiodopyridine and (RS)-6-methyl-morpholin-3-one (CAS 127958-63-8). 
       Step 2: (RS)-6-Methyl-4-(5-phenylethynyl-pyridin-2-yl)-morpholin-3-one 
       [1016]    
       
                 
         
             
             
         
       
     
         [1017]    The title compound was obtained as a light yellow solid, MS: m/e=293.1 (M+H + ), using chemistry similar to that described in Example 1, step 3 from (RS)-4-(5-iodo-pyridin-2-yl)-6-methyl-morpholin-3-one (Example 171, step 1) with phenylacetylene. 
       Example 172 
     6,6-Dimethyl-4-(5-phenylethynyl-pyridin-2-yl)-morpholin-3-one 
       [1018]    
       
                 
         
             
             
         
       
     
       Step 1: (2-Dibenzylamino-1,1-dimethyl-ethoxy)-acetic acid ethyl ester 
       [1019]    
       
                 
         
             
             
         
       
     
         [1020]    (4.9 g, 18.2 mmol) 1-(Dibenzylamino)-2-methylpropan-2-ol (CAS 344868-41-3) was dissolved in dichloroethane (50 ml) and ethyl 2-diazoacetate (2.83 ml, 27.3 mmol, 1.5 equiv.) and rhodium(II) acetate dimer (200 mg, 0.455 mmol, 0.025 equiv.) were added carefully at room temperature. The mixture was stirred for 3 hours at 80° C. The reaction mixture was evaporated with isolute and the crude product was purified by flash chromatography by directly loading the residue onto a silica gel column and eluting with a heptane:ethyl acetate gradient 100:0 to 70:30. The desired (2-dibenzylamino-1,1-dimethyl-ethoxy)-acetic acid ethyl ester (1.03 g, 80% purity, 13% yield) was obtained as a colorless liquid, MS: m/e=356.3 (M+H + ). 
       Step 2: 6,6-Dimethyl-morpholin-3-one 
       [1021]    
       
                 
         
             
             
         
       
     
         [1022]    (2-Dibenzylamino-1,1-dimethyl-ethoxy)-acetic acid ethyl ester (Example 172, step 1) was hydrogenated in EtOH with Pd(OH) 2  for 16 hours at 60° C. The desired 6,6-dimethyl-morpholin-3-one (585 mg, 60% purity, quant.) was obtained as a colorless liquid, MS: m/e=129 (M+H + ) and used in the next step without further purification. 
       Step 3: 6,6-Dimethyl-4-(5-trimethylsilanylethynyl-pyridin-2-yl)-morpholin-3-one 
       [1023]    
       
                 
         
             
             
         
       
     
         [1024]    The title compound was obtained as a yellow oil, MS: m/e=303.2 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2-bromo-5-trimethylsilanylethynyl-pyridine (Example 37, step 1) and 6,6-dimethyl-morpholin-3-one (Example 172, step 2). 
       Step 4: 6,6-Dimethyl-4-(5-phenylethynyl-pyridin-2-yl)-morpholin-3-one 
       [1025]    
       
                 
         
             
             
         
       
     
         [1026]    The title compound was obtained as a white solid, MS: m/e=307.3 (M+H + ), using chemistry similar to that described in Example 37, step 3 from 6,6-dimethyl-4-(5-trimethylsilanylethynyl-pyridin-2-yl)-morpholin-3-one (Example 172, step 3) and iodobenzene. 
       Example 173 
     1,1-Dioxo-4-(5-phenylethynyl-pyridin-2-yl)-thiomorpholin-3-one 
       [1027]    
       
                 
         
             
             
         
       
     
       Step 1: 4-(5-Bromo-pyridin-2-yl)-thiomorpholin-3-one 
       [1028]    
       
                 
         
             
             
         
       
     
         [1029]    The title compound was obtained as a yellow solid, MS: m/e=273.0/274.9 (M+H + ), using chemistry similar to that described in Example 37, step 2 from 2,5-dibromopyridine and thiomorpholin-3-one. 
       Step 2: 4-(5-Bromo-pyridin-2-yl)-1,1-dioxo-thiomorpholin-3-one 
       [1030]    
       
                 
         
             
             
         
       
     
         [1031]    (240 mg, 0.88 mmol) 4-(5-Bromo-pyridin-2-yl)-thiomorpholin-3-one (Example 173, step 1) was dissolved in dichloroethane (10 ml) and mCPBA (300 mg, 1.76 mmol, 2 equiv.) was added at 0-5° C. The mixture was stirred for 2 hours at 20-25° C. The reaction mixture was extracted with saturated NaHCO 3  solution and five times dichloromethane. The organic layers were combined, dried over Na 2 SO 4  and evaporated to dryness. The desired 4-(5-bromo-pyridin-2-yl)-1,1-dioxo-thiomorpholin-3-one (167 mg, 62% yield) was obtained as a light brown solid, MS: m/e=305.1/307.1 (M+H + ). 
       Step 3: 1,1-Dioxo-4-(5-phenylethynyl-pyridin-2-yl)-thiomorpholin-3-one 
       [1032]    
       
                 
         
             
             
         
       
     
         [1033]    The title compound was obtained as a light brown solid, MS: m/e=327.2 (M+H + ), using chemistry similar to that described in Example 1, step 3 from 4-(5-bromo-pyridin-2-yl)-1,1-dioxo-thiomorpholin-3-one (Example 173, step 2) and phenylacetylene. 
       Example 174 
       [1034]    (3 aSR,6aRS)-1-[6-(3-Fluoro-phenylethynyl)-pyridazin-3-yl]-3-methyl-hexahydro-cyclopentaimidazol-2-one 
         [0000]    
       
                 
         
             
             
         
       
     
       Step 1: 3-Chloro-6-(3-fluoro-phenylethynyl)-pyridazine 
       [1035]    
       
                 
         
             
             
         
       
     
         [1036]    To a well stirred solution of 2-chloro-5-iodopyrazine (600 mg, 2.5 mmol), 3-fluorophenyl-acetylene (315 mg, 303 μl, 2.62 mmol, 1.05 equiv.) in 7 ml of THF were added under argon atmosphere bis(triphenylphosphine)-palladium(II)dichloride (175 mg, 0.250 mmol, 0.02 equiv.), copper(I) iodide (23.8 mg, 0.125 mmol, 0.01 equiv.) and triethylamine (556 mg, 761 ul, 5.49 mmol, 2.2 equiv.). The mixture was stirred for 2 hours at room temperature. The crude mixture was filtered, adsorbed on silicagel and purified by flash chromatography over a 50 g silicagel column using a heptane to 25% ethyl acetate in heptane gradient. The title compound (450 mg, 78% yield) was obtained as a crystalline light-yellow solid, MS: m/e=233.1, 235.0 (M+H + ). 
       Step 2: (3aSR,6aRS)-1-[6-(3-Fluoro-phenylethynyl)-pyridazin-3-yl]-3-methyl-hexahydro-cyclopentaimidazol-2-one 
       [1037]    
       
                 
         
             
             
         
       
     
         [1038]    The title compound, an off-white solid, MS: m/e=337.2 (M+H + ), was prepared in accordance with the general method of Example 170; starting from 3-chloro-6-((3-fluorophenyl)-ethynyl)pyridazine and (3aRS, 6aSR)-1-methyl-hexahydro-cyclopentaimidazol-2-one.