Tetracyclic inhibitors of fatty acid amide hydrolase

Abstract

Certain tetracyclic compounds are described, which may be used in pharmaceutical compositions and methods for treating disease states, disorders, and conditions mediated by fatty acid amide hydrolase (FAAH) activity. Thus, the compounds may be administered to treat, e.g., anxiety, pain, inflammation, sleep disorders, eating disorders, or movement disorders (such as multiple sclerosis).

What is claimed is: 
     
         1 . A compound of Formula (I): 
       
         
           
           
               
               
           
         
         wherein 
         R 1  is H; 
         R 2  is pyridyl optionally substituted with R x ; 
         or R 1  and R 2  taken together with the oxazole to which they are attached form oxazolo[4,5-b]pyridin-2-yl;
 where R x  is —C 1-6 alkyl; —C 3-6 cycloalkyl; —CF 3 ; —CN; —C(O)C 1-4 alkyl optionally substituted with one, two, or three fluoro substituents; —CO 2 C 1-4 alkyl; —CO 2 H; —C(O)N(R a )R b ; —OH; —OC 1-6 alkyl; halo; —NO 2 ; —NR a R b ; —N(R a )C(O)R b ; —N(R a )SO 2 R b ; —SO 2 N(R a )R b ; —S(O) 0-2 R f ; or tetrazolyl;
 where R a  and R b  are each independently —H, —C 1-6 alkyl, or —C 3-6 cycloalkyl; and 
 R f  is —C 1-4 alkyl optionally substituted with one, two, or three fluoro substituents; 
 
 
         R 3  is —H; —C 1-6 alkyl; C 3-6 cycloalkyl; —CF 3 ; —CN; —C(O)C 1-4 alkyl optionally substituted with one, two, or three fluoro substituents; —CO 2 C 1-4 alkyl; —CO 2 H; —C(O)N(R c )R d ; —OH; —OC 1-6 alkyl; -halo; —NO 2 ; —NR c R d ; —N(R c )C(O)R d ; —N(R c )SO 2 R d ; —SO 2 N(R c )R d ; —S(O) 0-2 R f ; or —CH 2 N(R g )R h ;
 where R c  and R d  are each independently —H, —C 1-6 alkyl, or —C 3-6 cycloalkyl; 
 R f  is —C 1-4 alkyl optionally substituted with one, two, or three fluoro substituents; and 
 R g  and R h  are each independently H or C 1-4 alkyl; or R g  and R h  taken together with the nitrogen to which they are attached form a monocyclic saturated heterocycloalkyl group; 
 
         X is —CH 2 —, —O—, —S—, —S(O)—, —S(O) 2 —, —N(R i )—, or —CH(OH)—; and 
         Y is absent or is —CH 2 —, —O—, —S—, —S(O)—, —S(O) 2 —, —NR i —, —CH 2 O—, or —OCH 2 —;
 wherein R i  is —H or —C 1-6 alkyl; and provided that when Y is absent, a single bond is present between the two phenyl rings of formula I; 
 
         a pharmaceutically acceptable salt of a compound of Formula (I), a pharmaceutically acceptable prodrug of a compound of Formula (I), or a pharmaceutically active metabolite of a compound of Formula (I). 
       
     
     
         2 . A compound according to  claim 1  wherein R 2  is unsubstituted 2-pyridyl. 
     
     
         3 . A compound according to  claim 1  wherein R 2  is 2-pyridyl substituted with —CN, —CO 2 Me, —CO 2 Et, —CO 2 H, or —CONH 2 . 
     
     
         4 . A compound according to  claim 1  selected from the group consisting of compounds of Formula (I) wherein R 3  is —H. 
     
     
         5 . A compound according to  claim 1  wherein R 3  is —CH 2 N(R g )R h . 
     
     
         6 . A compound according to  claim 5  wherein R g  and R h  are both methyl. 
     
     
         7 . A compound according to  claim 5  wherein R g  and R h  are taken together with the nitrogen to which they are attached to form piperidine, morpholine, thiomorpholine, pyrrolidine, or N-methylpiperazine. 
     
     
         8 . A compound according to  claim 1  wherein X is —CH 2 — or —O—. 
     
     
         9 . A compound according to  claim 1  wherein X is —O—. 
     
     
         10 . A compound according to  claim 8  wherein X is —CH 2 —. 
     
     
         11 . A compound according to  claim 1  wherein Y is absent or is —CH 2 —, —O—, —S—, —NH—, or —CH 2 O—. 
     
     
         12 . A compound of  claim 1  selected from the group consisting of:
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(benzyloxy)phenyl)propane; 
 2-(4-(Benzyloxy)phenoxy)-1-(5-(pyridin-2-yl)oxazol-2-yl)ethanone; 
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(3-(benzyloxy)phenyl)-propane; 
 2-(3-(Benzyloxy)phenoxy)-1-(5-(pyridin-2-yl)oxazol-2-yl)ethanone; 
 3-(4-(Phenoxymethyl)phenyl)-1-(5-(pyridin-2-yl)oxazol-2-yl)propan-1-one; 
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-phenoxyphenyl)propane; 
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(phenylamino)phenyl)propane; 
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-benzylphenyl)propane; 
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(phenylthio)phenyl)propane; 
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-biphenyl)propane; 
 3-(4-(Benzyloxy)phenyl)-1-(oxazolo[4,5-b]pyridin-2-yl)propan-1-one; 
 6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester; 
 6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid methyl ester; 
 6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid; 
 6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid; 
 6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester; 
 6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid methyl ester; 
 6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid; 
 6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carbonitrile; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid ethyl ester; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinic acid methyl ester; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinic acid; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid amide; 
 6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinamide; 
 4-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester; 
 4-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid; 
 3-Biphenyl-4-yl-1-(5-pyridin-4-yl-oxazol-2-yl)-propan-1-one; 
 3-Biphenyl-4-yl-1-(5-pyridin-3-yl-oxazol-2-yl)-propan-1-one; 
 5-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester; 
 5-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid; 
 6-{2-[3-(4′-Piperidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester; 
 6-{2-[3-(4′-Morpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester; 
 6-{2-[3-(4′-Thiomorpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester; 
 6-{2-[3-(4′-Pyrrolidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester; 
 6-{2-[3-(4′-Dimethylaminomethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester; 
 6-(2-{3-[4′-(4-Methyl-piperazin-1-ylmethyl)-biphenyl-4-yl]-propionyl}-oxazol-5-yl)-pyridine-2-carboxylic acid methyl ester; 
 6-{2-[3-(4′-Piperidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid; 
 6-{2-[3-(4′-Morpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid; 
 6-{2-[3-(4′-Thiomorpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid; 
 6-{2-[3-(4′-Pyrrolidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid; 
 6-{2-[3-(4′-Dimethylaminomethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid; 
 6-(2-{3-[4′-(4-Methyl-piperazin-1-ylmethyl)-biphenyl-4-yl]-propionyl}-oxazol-5-yl)-pyridine-2-carboxylic acid; 
 3-Biphenyl-4-yl-1-{5-[6-(1H-tetrazol-5-yl)-pyridin-2-yl]-oxazol-2-yl}-propan-1-one; 
 3-(4-Phenoxymethyl-phenyl)-1-{5-[6-(1H-tetrazol-5-yl)-pyridin-2-yl]-oxazol-2-yl}-propan-1-one; and 
 6-{2-[3-(4-phenoxymethylphenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carbonitrile; 
 or 
 a pharmaceutically acceptable salt thereof; 
 or any combination thereof. 
 
     
     
         13 . A pharmaceutical composition for treating a disease, disorder, or medical condition mediated by FAAH activity, comprising:
 (a) an effective amount of at least one compound of Formula (I) of  claim 1  or a pharmaceutically acceptable salt, a pharmaceutically acceptable prodrug, or a pharmaceutically active metabolite thereof, or any combination thereof;   
       and
 (b) a pharmaceutically acceptable excipient. 
 
     
     
         14 . A pharmaceutical composition according to  claim 13 , wherein the compound of Formula (I) is:
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(benzyloxy)phenyl)propane;   2-(4-(Benzyloxy)phenoxy)-1-(5-(pyridin-2-yl)oxazol-2-yl)ethanone;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(3-(benzyloxy)phenyl)-propane;   2-(3-(Benzyloxy)phenoxy)-1-(5-(pyridin-2-yl)oxazol-2-yl)ethanone;   3-(4-(Phenoxymethyl)phenyl)-1-(5-(pyridin-2-yl)oxazol-2-yl)propan-1-one;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-phenoxyphenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(phenylamino)phenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-benzylphenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(phenylthio)phenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-biphenyl)propane;   3-(4-(Benzyloxy)phenyl)-1-(oxazolo[4,5-b]pyridin-2-yl)propan-1-one;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid methyl ester;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid methyl ester;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carbonitrile;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid ethyl ester;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinic acid methyl ester;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinic acid;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid amide;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinamide;   4-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester;   4-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid;   3-Biphenyl-4-yl-1-(5-pyridin-4-yl-oxazol-2-yl)-propan-1-one;   3-Biphenyl-4-yl-1-(5-pyridin-3-yl-oxazol-2-yl)-propan-1-one;   5-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester;   5-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Piperidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Morpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Thiomorpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Pyrrolidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Dimethylaminomethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-(2-{3-[4′-(4-Methyl-piperazin-1-ylmethyl)-biphenyl-4-yl]-propionyl}-oxazol-5-yl)-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Piperidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Morpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Thiomorpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Pyrrolidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Dimethylaminomethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-(2-{3-[4′-(4-Methyl-piperazin-1-ylmethyl)-biphenyl-4-yl]-propionyl}-oxazol-5-yl)-pyridine-2-carboxylic acid;   3-Biphenyl-4-yl-1-{5-[6-(1H-tetrazol-5-yl)-pyridin-2-yl]-oxazol-2-yl}-propan-1-one;   3-(4-Phenoxymethyl-phenyl)-1-{5-[6-(1H-tetrazol-5-yl)-pyridin-2-yl]-oxazol-2-yl}-propan-1-one; or   6-{2-[3-(4-phenoxymethylphenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carbonitrile;   or a pharmaceutically acceptable salt thereof, or any combination thereof.   
     
     
         15 . A pharmaceutical composition according to  claim 13 , further comprising: an analgesic selected from the group consisting of opioids and non-steroidal anti-inflammatory drugs. 
     
     
         16 . A pharmaceutical composition according to  claim 13 , further comprising: an active ingredient selected from the group consisting of aspirin, acetaminophen, opioids, ibuprofen, naproxen, COX-2 inhibitors, gabapentin, pregabalin, and tramadol. 
     
     
         17 . A method of treating a subject suffering from or diagnosed with a disease, disorder, or medical condition mediated by FAAH activity, comprising administering to the subject in need of such treatment an effective amount of at least one compound of Formula (I) of  claim 1 , a pharmaceutically acceptable salt of a compound of Formula (I), a pharmaceutically acceptable prodrug of a compound of Formula (I), or a pharmaceutically active metabolite of a compound of Formula (I). 
     
     
         18 . A method according to  claim 17 , wherein the compound of Formula (I) is:
 1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(benzyloxy)phenyl)propane;   2-(4-(Benzyloxy)phenoxy)-1-(5-(pyridin-2-yl)oxazol-2-yl)ethanone;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(3-(benzyloxy)phenyl)-propane;   2-(3-(Benzyloxy)phenoxy)-1-(5-(pyridin-2-yl)oxazol-2-yl)ethanone;   3-(4-(Phenoxymethyl)phenyl)-1-(5-(pyridin-2-yl)oxazol-2-yl)propan-1-one;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-phenoxyphenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(phenylamino)phenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-benzylphenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-(phenylthio)phenyl)propane;   1-Oxo-1-[5-(2-pyridyl)oxazol-2-yl]-3-(4-biphenyl)propane;   3-(4-(Benzyloxy)phenyl)-1-(oxazolo[4,5-b]pyridin-2-yl)propan-1-one;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid methyl ester;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4-Phenoxy-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid methyl ester;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4-Phenoxymethyl-phenyl)-propionyl]-oxazol-5-yl}-nicotinic acid;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carbonitrile;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid ethyl ester;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinic acid methyl ester;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinic acid;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid amide;   6-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-nicotinamide;   4-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester;   4-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid;   3-Biphenyl-4-yl-1-(5-pyridin-4-yl-oxazol-2-yl)-propan-1-one;   3-Biphenyl-4-yl-1-(5-pyridin-3-yl-oxazol-2-yl)-propan-1-one;   5-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid methyl ester;   5-[2-(3-Biphenyl-4-yl-propionyl)-oxazol-5-yl]-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Piperidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Morpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Thiomorpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Pyrrolidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Dimethylaminomethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid methyl ester;   6-(2-{3-[4′-(4-Methyl-piperazin-1-ylmethyl)-biphenyl-4-yl]-propionyl}-oxazol-5-yl)-pyridine-2-carboxylic acid methyl ester;   6-{2-[3-(4′-Piperidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Morpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Thiomorpholin-4-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Pyrrolidin-1-ylmethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-{2-[3-(4′-Dimethylaminomethyl-biphenyl-4-yl)-propionyl]-oxazol-5-yl}-pyridine-2-carboxylic acid;   6-(2-{3-[4′-(4-Methyl-piperazin-1-ylmethyl)-biphenyl-4-yl]-propionyl}-oxazol-5-yl)-pyridine-2-carboxylic acid;   3-Biphenyl-4-yl-1-{5-[6-(1H-tetrazol-5-yl)-pyridin-2-yl]-oxazol-2-yl}-propan-1-one;   3-(4-Phenoxymethyl-phenyl)-1-{5-[6-(1H-tetrazol-5-yl)-pyridin-2-yl]-oxazol-2-yl}-propan-1-one; or   6-{2-[3-(4-phenoxymethylphenyl)-propionyl]-oxazol-5-yl}-pyridine-2-carbonitrile;   or a pharmaceutically acceptable salt thereof,   or any combination thereof.   
     
     
         19 . A method according to  claim 17 , wherein the disease, disorder, or medical condition is selected from the group consisting of: anxiety, depression, pain, sleep disorders, eating disorders, inflammation, movement disorders, HIV wasting syndrome, closed head injury, stroke, learning and memory disorders, Alzheimer's disease, epilepsy, Tourette's syndrome, Niemann-Pick disease, Parkinson's disease, Huntington's chorea, optic neuritis, autoimmune uveitis, drug withdrawal, nausea, emesis, sexual dysfunction, post-traumatic stress disorder, cerebral vasospasm, glaucoma, irritable bowel syndrome, inflammatory bowel disease, immunosuppression, gastroesophageal reflux disease, paralytic ileus, secretory diarrhea, gastric ulcer, rheumatoid arthritis, unwanted pregnancy, hypertension, cancer, hepatitis, allergic airway disease, autoimmune diabetes, intractable pruritis, and neuroinflammation. 
     
     
         20 . A method according to  claim 17 , wherein the disease, disorder, or medical condition is selected from the group consisting of: anxiety, pain, inflammation, sleep disorders, eating disorders, and movement disorders.