3,4-substituted pyrrolidine beta-secretase inhibitors for the treatment of alzheimer's disease

1. A compound of formula (I)

Y 1 is phenyl, which is optionally substituted with one or more

(a) —C 1-6 alkyl,

(b) —C 1-6 alkyl-C 3-6 cycloalkyl,

(c) —C 6-10 aryl,

(d) halogen,

(e) —O—C 1-6 alkyl,

(f) —CN,

(g) a heterocyclic group having 4 to 8 ring atoms, wherein one ring atom is a heteroatom selected from the group consisting of nitrogen, sulfur or oxygen, and

(h) heteroaryl,

and wherein said alkyl, aryl, cycloalkyl, heterocyclic, or heteroaryl moiety is optionally substituted with one or more

(i) halo,

(ii) —OH,

(iii) —CN,

(iv) —C 1-6 alkyl,

(v) —C 2-6 alkenyl,

(vi) —C 3-6 cycloalkyl,

(vii) —O—C 1-6 alkyl,

(viii) —O—(CH 2 ) p -aryl,

(ix) aryl,

(x) heteroaryl,

(xi) —NR 6A R 6B ,

(xii) —C(═O)—R 6C ,

(xiii) —C(═O)—NR 6A R 6B ,

(xiv) —NR 6A (C═O)R 6B ,

(xiv) —C(═O)—OR 6C ,

(xv) —NSO 2 R 6A R 6B ,

(xvi) —SO 2 —R 6C ,

(xvii) —(SO 2 )NR 6A R 6B ,

wherein R 6A and R 6B are selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl,

(III) —C 3-6 cycloalkyl,

or R 6A and R 6B are linked together with the nitrogen to which they are both attached to form a 2-6 membered carbocyclic ring,

wherein one or two of the ring carbon atoms is replaced by a nitrogen, oxygen or sulfur,

and R 6C is selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl, and

(III) —C 3-6 cycloalkyl;

Y 2 is hydrogen or methyl;

R 2 is selected from the group consisting of

(1) hydrogen

(2) C 1-6 alkyl,

(3) —C 1-6 alkyl-C 3-6 cycloalkyl,

(4) —(CH 2 ) m aryl,

(5) heteroaryl,

(6) —O—C 1-6 alkyl,

(7) —C(═O)—OR 6C , and

(8) a heterocyclic group having 4 to 8 ring atoms, wherein one ring atom is a heteroatom selected from the group consisting of nitrogen, sulfur or oxygen, and

wherein said alkyl, aryl, cycloalkyl, heterocyclic or heteroaryl R 2 moiety is optionally substituted with one or more

(a) halo,

(b) —OH,

(c) —CN,

(d) —C 1-6 alkyl

(e) —C 3-6 cycloalkyl,

(f) —O—C 1-6 alkyl,

(g) —O—CH 2 -aryl,

(h) aryl,

(i) heteroaryl,

(j) —NR 6A R 6B ,

(k) —NR 6A C(═O)R 6B ,

(l) a heterocyclic group having 4 to 8 ring atoms, wherein one ring atom is a heteroatom selected from the group consisting of nitrogen, sulfur and oxygen,

(m) —SO 2 C 1-3 alkyl,

(n) —SO 2 NR 6A R 6B ,

(o) —CONR 6A R 6B , and

(p) a heterocyclic group having 4 to 8 ring atoms, wherein one ring atom is a heteroatom selected from the group consisting of nitrogen, sulfur and oxygen;

wherein R 6A and R 6B are selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl,

(III) —C 3-6 cycloalkyl,

or R 6A and R 6B are linked together with the nitrogen to which they are both attached to form a 2-6 membered carbocyclic ring,

wherein one or two of the ring carbon atoms is replaced by a nitrogen, oxygen or sulfur,

and R 6C is selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl, and

(III) —C 3-6 cycloalkyl;

X is selected from the group consisting of

(1) —CR 5 R 6 —O—CR 7 R 8 —

(2) —CR 5 R 6 CR 7 R 8 —O—CR 9 R 10 —

(3) —CR 5 R 6 —

(4) —CR 5 R 6 CR 7 R 8 —

(5) —CH 2 CR 7 R 8 CH 2 —

(6) —CR 5 ═CR 6 CR 7 R 8 —

(7) —CR 5 R 6 CR 7 R 8 CR 9 R 10 CR 11 R 12 —;

R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 and R 12 are independently selected from the group consisting of:

(1) hydrogen,

(2) C 1-6 alkyl,

(3) OH

(4) —(CH 2 ) m aryl

wherein said alkyl or aryl moiety is optionally substituted with one or more

(a) halo,

(b) —C 1-6 alkyl,

(c) —O—C 1-6 alkyl, and

(d) -aryl,

wherein said wherein said alky or aryl is optionally substituted with one or more halo,

or R 5 and R 6 , or R 7 and R 8 , or R 9 and R 10 , or R 11 and R 12 are linked together to form an aromatic or non-aromatic spirocyclic group of 5-10 ring carbon atoms, wherein one or two of the ring carbon atoms is replaced by an oxygen, nitrogen or sulfur,

or R 5 and R 6 , and R 7 and R 8 , are linked together to form to form a fused aromatic or non-aromatic cyclic group of 5-10 ring carbon atoms, wherein one or two of the ring carbon atoms is replaced by an oxygen, nitrogen or sulfur,

or R 2 and R 5 are linked together to form to form a fused aromatic or non-aromatic cyclic group of 5-10 ring carbon atoms, wherein one or two of the ring carbon atoms is replaced by an oxygen, nitrogen or sulfur;

m is 0, 1 or 2;

p is 0 or 1;

or a pharmaceutically acceptable salt thereof.

2. A compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Y 1 is phenyl, which is substituted by one or more

(1) —C 1-6 alkyl, wherein said alkyl is optionally substituted with one or more fluoro,

(2) halogen, and

(3) —O—C 1-6 alkyl, wherein said alkyl is optionally substituted with one or more fluoro.

3. A compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Y 1 is phenyl, which is substituted by one or more phenyl, wherein said phenyl is optionally substituted with one or more

(a) halo,

(b) —OH,

(c) —CN,

(d) —C 1-6 alkyl,

(e) —C 2-6 alkenyl,

(f) —C 3-6 cycloalkyl,

(g) —O—C 1-6 alkyl,

(h) —O—(CH 2 ) p -aryl,

(i) aryl,

(j) heteroaryl,

(k) —NR 6A R 6B ,

(l) —C(═O)—R 6C ,

(m) —C(═O)—NR 6A R 6B ,

(n) —NR 6A (C═O)R 6B ,

(o) —C(═O)—OR 6C ,

(p) —NSO 2 R 6A R 6B ,

(q) —SO 2 —R 6C , and

(r) —(SO 2 )NR 6A R 6B .

4. A compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein Y 2 is hydrogen.

5. A compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 2 is selected from the group consisting of:

(1) phenyl, and

(2) benzyl.

6. A compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein X is selected from the group consisting of

(1) —CR 5 R 6 —O—CR 7 R 8 —,

(2) —CR 5 R 6 CR 7 R 8 —O—CR 9 R 10 —,

(3) —CR 5 R 6 CR 7 R 8 —, and

(4) —CR 5 R 6 CR 7 R 8 CR 9 R 10 —.

7. A compound of claim 1 , or a pharmaceutically acceptable salt thereof,

wherein the compound of formula (I) is a compound of formula (II)

or a pharmaceutically acceptable salt thereof,

wherein R 1A and R 1B are selected from the group consisting of

(a) —C 1-6 alkyl,

(b) —C 1-6 alkyl-C 3-6 cycloalkyl,

(c) —C 6-10 aryl,

(d) halogen,

(e) —O—C 1-6 alkyl,

(f) —CN,

(g) a heterocyclic group having 4 to 8 ring atoms, wherein one ring atom is a heteroatom selected from the group consisting of nitrogen, sulfur or oxygen, and

(h) heteroaryl,

and wherein said alkyl, aryl, cycloalkyl, heterocyclic, or heteroaryl moiety is optionally substituted with one or more

(i) halo,

(ii) —OH,

(iii) —CN,

(iv) —C 1-6 alkyl,

(v) —C 2-6 alkenyl,

(vi) —C 3-6 cycloalkyl,

(vii) —O—C 1-6 alkyl,

(viii) —O—(CH 2 ) p -aryl,

(ix) aryl,

(x) heteroaryl,

(xi) —NR 6A R 6B ,

(xii) —C(═O)—R 6C ,

(xiii) —C(═O)—NR 6A R 6B ,

(xiv) —NR 6A (C═O)R 6B ,

(xiv) —C(═O)—OR 6C ,

(xv) —NSO 2 R 6A R 6B ,

(xvi) —SO 2 —R 6C ,

(xvii) —(SO 2 )NR 6A R 6B ,

wherein R 6A and R 6B are selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl,

(III) —C 3-6 cycloalkyl,

or R 6A and R 6B are linked together with the nitrogen to which they are both attached to form a 2-6 membered carbocyclic ring, wherein one or two of the ring carbon atoms is replaced by a nitrogen, oxygen or sulfur,

and R 6C is selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl, and

(III) —C 3-6 cycloalkyl.

8. A compound of claim 1 , or a pharmaceutically acceptable salt thereof,

wherein the compound of formula (I) is a compound of formula (III):

wherein R 1A is selected from the group consisting of

(a) —C 1-6 alkyl,

(b) —C 1-6 alkyl-C 3-6 cycloalkyl,

(c) —C 6-10 aryl,

(d) halogen,

(e) —O—C 1-6 alkyl,

(f) —CN,

(g) a heterocyclic group having 4 to 8 ring atoms, wherein one ring atom is a heteroatom selected from the group consisting of nitrogen, sulfur or oxygen, and

(h) heteroaryl,

and wherein said alkyl, aryl, cycloalkyl, heterocyclic, or heteroaryl moiety is optionally substituted with one or more

(i) halo,

(ii) —OH,

(iii) —CN,

(iv) —C 1-6 alkyl,

(v) —C 2-6 alkenyl,

(vi) —C 3-6 cycloalkyl,

(vii) —O—C 1-6 alkyl,

(viii) —O—(CH 2 ) p -aryl,

(ix) aryl,

(x) heteroaryl,

(xi) —NR 6A R 6B ,

(xii) —C(═O)—R 6C ,

(xiii) —C(═O)—NR 6A R 6B ,

(xiv) —NR 6A (C═O)R 6B ,

(xiv) —C(═O)—OR 6C ,

(xv) —NSO 2 R 6A R 6B ,

(xvi) —SO 2 —R 6C ,

(xvii) —(SO 2 )NR 6A R 6B ,

wherein R 6A and R 6B are selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl,

(III) —C 3-6 cycloalkyl,

or R 6A and R 6B are linked together with the nitrogen to which they are both attached to form a 2-6 membered carbocyclic ring, wherein one or two of the ring carbon atoms is replaced by a nitrogen, oxygen or sulfur,

and R 6C is selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl, and

(III) —C 3-6 cycloalkyl.

9. A compound of claim 8 , wherein R 1A is phenyl, which is unsubstituted or substituted with one or more groups selected from the group consisting of:

(i) halo,

(ii) —OH,

(iii) —CN,

(iv) —C 1-6 alkyl,

(v) —C 2-6 alkenyl,

(vi) —C 3-6 cycloalkyl,

(vii) —O—C 1-6 alkyl,

(viii) —O—(CH 2 ) p -aryl,

(ix) aryl,

(x) heteroaryl,

(xi) —NR 6A R 6B ,

(xii) —C(═O)—R 6C ,

(xiii) —C(═O)—NR 6A R 6B ,

(xiv) —NR 6A (C═O)R 6B ,

(xiv) —C(═O)—OR 6C ,

(xv) —NSO 2 R 6A R 6B ,

(xvi) —SO 2 —R 6C ,

(xvii) —(SO 2 )NR 6A R 6B ,

wherein R 6A and R 6B are selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl,

(III) —C 3-6 cycloalkyl,

or R 6A and R 6B are linked together with the nitrogen to which they are both attached to form a 2-6 membered carbocyclic ring, wherein one or two of the ring carbon atoms is replaced by a nitrogen, oxygen or sulfur,

and R 6C is selected from the group consisting of

(I) hydrogen,

(II) —C 1-6 alkyl, and

(III) —C 3-6 cycloalkyl.

10. A compound of claim 1 , or a pharmaceutically acceptable salt thereof,

wherein the compound of formula (I) is a compound of formula (IV):

11. A compound of claim 1 , or a pharmaceutically acceptable salt thereof,

wherein the compound of formula (I) is a compound of formula (V):

or a pharmaceutically acceptable salt thereof.

12. A compound of claim 1 , or pharmaceutically acceptable salt thereof,

wherein the compound of formula (I) is a compound of formula (VI):

13. A compound of claim 1 , which is selected from the group consisting of

2-benzyl-1-{[(3S,4R)-4-(2-methylphenyl)pyrrolidine-3-yl]carbonyl}pyrrolidine;

(3S)-4-{[3S,4R]-4-(2-bromophenyl)pyrrolidine-3-yl}carbonyl}-3-phenylmorpholine;

(3S)-4-{[3S,4R]-4-(4′-ethoxybiphenyl-2-yl)pyrrolidin-3-yl}carbonyl}-3-phenylmorpholine;

2-benzyl-1-{[(3S,4R)-4-(2-chlorophenyl)pyrrolidin-3-yl]carbonyl}pyrrolidine;

(3S)-4-{[(3S,4R)-4-(2-methoxyphenyl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

2-benzyl-1-{[(3S,4R)-4-phenylpyrrolidin-3-yl]carbonyl}pyrrolidine;

(3S)-4-{[(3S,4R)-4-biphenyl-2-ylpyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

2-benzyl-1{-[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}pyrrolidine;

(3S)-4-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-4-({(3S,4R)-4-[2-(1-methyl-1H-pyrazol-4-yl)phenyl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(2′-fluorobiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(4′-ethoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-[2-(4-chlorophenyl)ethyl]piperidine;

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-3H-spiro[2-benzofuran-1,4′-piperidine];

2-benzyl-1-{[(3S,4R)-4-(4′-ethoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}pyrrolidine;

4-(2-{(3S,4S)-4-[(2-benzylpyrrolidin-1-yl)carbonyl]pyrrolidin-3-yl}phenyl)-1-methyl-1H-pyrazole;

2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-carbonitrile;

2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-3-carbonitrile;

(3S)-3-phenyl-4-({(3S,4R)-4-[3′-(trifluoromethyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)morpholine;

N-[2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-3-yl]methanesulfonamide;

(3S)-4-({(3S,4R)-4-[2-(2,3-dihydro-1,4-benzodioxin-6-yl)phenyl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(4′-fluoro-2′-methylbiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-3-phenyl-4-({(3S,4R)-4-[2-(3-thienyl)phenyl]pyrrolidin-3-yl}carbonyl)morpholine;

(3S)-4-({(3S,4R)-4-[2′-(benzyloxy)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(4′-isobutylbiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

1-methyl-5-[2-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)phenyl]-1H-indole;

(3S)-4-({(3S,4R)-4-[4′-(methylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

1-[2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-yl]ethanone;

(3S)-4-({(3S,4R)-4-[4′-(morpholin-4-ylcarbonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

N-cyclopropyl-2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-carboxamide;

N-methyl-2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-amine;

{[2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-yl]oxy}acetonitrile;

(3S)-4-({(3S,4R)-4-[2-(6-chloropyridin-3-yl)phenyl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

(3S)-4-({(3S,4R)-4-[2-(3,5-dimethylisoxazol-4-yl)phenyl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

(3S)-4-({(3S,4R)-4-[2-(3-furyl)phenyl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

5-[2-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)phenyl]pyridin-2-ol;

(3S)-4-[((3S,4R)-4-{2-[(1Z)-1-methylprop-1-en-1-yl]phenyl}pyrrolidin-3-yl)carbonyl]-3-phenylmorpholine;

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}spiro[indene-1,4′-piperidine];

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-phenylazepane;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-(2-phenylethyl)pyrrolidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-phenylpiperidine;

2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-ol;

(3S)-4-{[(3S,4R)-4-(4′-methylbiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(4′-fluorobiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

ethyl 2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-carboxylate;

N-[2′-((3R,4S)-4-{[(3S)-3-phenylmorpholin-4-yl]carbonyl}pyrrolidin-3-yl)biphenyl-4-yl]acetamide;

(3S)-4-({(3S,4R)-4-[2-(6-morpholin-4-ylpyridin-3-yl)phenyl]pyrrolidin-3-yl}carbonyl)-3-phenylmorpholine;

(3S)-3-phenyl-4-({(3S,4R)-4-[4′-(pyrrolidin-1-ylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)morpholine;

(3S)-4-{[(3S,4R)-4-(4′-tert-butylbiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-3-phenyl-4-{[(3S,4R)-4-(3′-propoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}morpholine;

(3S)-4-{[(3S,4R)-4-(3′-isopropoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(4′-isopropoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-3-phenyl-4-{[(3S,4R)-4-(4′-propoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}morpholine;

(3S)-3-phenyl-4-({(3S,4R)-4-[4′-(trifluoromethyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)morpholine;

(3S)-4-{[(3S,4R)-4-(2′-methyl-4′-propoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(4′-phenoxybiphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-4-{[(3S,4R)-4-(2′-fluoro-1,1′:4′,1″-terphenyl-2-yl)pyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

(3S)-3-phenyl-4-[((3S,4R)-4-{2-[(1E)-prop-1-en-1-yl]phenyl}pyrrolidin-3-yl)carbonyl]morpholine;

methyl (2S)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}piperidine-2-carboxylate;

methyl (2S)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}piperidine-2-carboxylate;

(3S)-3-benzyl-4-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}morpholine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-phenylpiperidine;

1-({(3S,4R)-4-[4′-(methylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-4-phenylpiperidine;

1′-({(3S,4R)-4-[4′-(methylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)spiro[indene-1,4′-piperidine];

(2R)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-(fluoromethyl)pyrrolidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-(4-methoxyphenyl)pyrrolidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-(3,5-dichlorophenyl)pyrrolidine;

1-({(3S,4R)-4-[4′-(methylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-2-phenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-(4-chlorophenyl)piperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-(2-fluorophenyl)piperidine;

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2,3-dihydrospiro[indene-1,4′-piperidine];

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-(4-methylphenyl)piperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

1-({(3S,4R)-4-[4′-(methylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-2,4-diphenylpiperidine;

2,4-diphenyl-1-{[(3S,4R)-4-phenylpyrrolidin-3-yl]carbonyl}piperidine;

(2R,4S)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2′-phenylspiro[indene-1,4′-piperidine];

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2′-phenylspiro[indene-1,4′-piperidine];

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2′-phenylspiro[indene-1,4′-piperidine];

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2′-(4-methoxyphenyl)spiro[indene-1,4′-piperidine];

1′-({(3S,4R)-4-[4′-(methylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-2′-phenylspiro[indene-1,4′-piperidine];

(2R,4S)-1-{[(3S,4R)-4-(2-allylphenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

2′-phenyl-1′-{[(3S,4R)-4-phenylpyrrolidin-3-yl]carbonyl}spiro[indene-1,4′-piperidine];

1′-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2′-(4-chlorophenyl)spiro[indene-1,4′-piperidine];

(2R,4S)-1-{[(3S,4R)-4-(2-allylphenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

(2R,4S)-2,4-diphenyl-1-({(3S,4R)-4-[2-(1H-pyrrol-2-yl)phenyl]pyrrolidin-3-yl}carbonyl)piperidine;

4-[2-((3R,4S)-4-{[(2R,4S)-2,4-diphenylpiperidin-1-yl]carbonyl}pyrrolidin-3-yl)phenyl]pyridine;

5-[2-((3R,4S)-4-{[(2R,4S)-2,4-diphenylpiperidin-1-yl]carbonyl}pyrrolidin-3-yl)phenyl]pyrimidine;

3-[2-((3R,4S)-4-{[(2R,4S)-2,4-diphenylpiperidin-1-yl]carbonyl}pyrrolidin-3-yl)phenyl]pyridine;

2-chloro-5-[2-((3R,4S)-4-{[(2R,4S)-2,4-diphenylpiperidin-1-yl]carbonyl}pyrrolidin-3-yl)phenyl]pyridine;

(2R,4S)-2,4-diphenyl-1-({(3S,4R)-4-[2-(1H-pyrazol-4-yl)phenyl]pyrrolidin-3-yl}carbonyl)piperidine;

(2R,4S)-1-({(3S,4R)-4-[2-(1-methyl-1H-pyrazol-4-yl)phenyl]pyrrolidin-3-yl}carbonyl)-2,4-diphenylpiperidine;

(2S,4S)-1-({(3S,4R)-4-[2-(1-isobutyl-1H-pyrazol-4-yl)phenyl]pyrrolidin-3-yl}carbonyl)-2,4-diphenylpiperidine;

(2S,4S)-1-[((3S,4R)-4-{2-[1-(3-methylbutyl)-1H-pyrazol-4-yl]phenyl}pyrrolidin-3-yl)carbonyl]-2,4-diphenylpiperidine;

(2R,4S)-2,4-diphenyl-1-({(3S,4R)-4-[2-(1-propyl-1H-pyrazol-4-yl)phenyl]pyrrolidin-3-yl}carbonyl)piperidine;

(2R,4S)-1-{[(3S,4R)-4-(2-cyclohex-1-en-1-ylphenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

(2S,4S)-1-{[(3S,4R)-4-(2-cyclopropylphenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

(2S,4S)-2,4-diphenyl-1-({(3S,4R)-4-[2-(2-thienyl)phenyl]pyrrolidin-3-yl}carbonyl)piperidine;

(2R,4S)-1-({(3S,4R)-4-[2-(1-benzofuran-2-yl)phenyl]pyrrolidin-3-yl}carbonyl)-2,4-diphenylpiperidine;

(2S,4S)-1-{[(3S,4R)-4-(2-methylphenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-3-phenylpyrrolidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-methyl-4-phenylpiperidine;

1-{[(3R,4R)-3-fluoro-4-phenylpyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

(2S,4S)-1-{[(3S,4R)-4-(3-bromophenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

2-((3R,4S)-4-{[(2R,4S)-2,4-diphenylpiperidin-1-yl]carbonyl}pyrrolidin-3-yl)benzonitrile;

(2R,4S)-1-({(3S,4R)-4-[3-(methoxymethyl)phenyl]pyrrolidin-3-yl}carbonyl)-2,4-diphenylpiperidine;

1-({(3S,4R)-4-[3-(methoxymethyl)phenyl]pyrrolidin-3-yl}carbonyl)-4-phenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-methyl-4-phenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-phenyl-4-vinylpiperidine;

3-((3R,4S)-4-{[(2R,4S)-2,4-diphenylpiperidin-1-yl]carbonyl}pyrrolidin-3-yl)benzonitrile;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-ethyl-4-phenylpiperidine;

(2S,4S)-1-({(3S,4R)-4-[3-(2-methoxyethyl)phenyl]pyrrolidin-3-yl}carbonyl)-2,4-diphenylpiperidine;

1-({(3S,4R)-4-[3-(2-methoxyethyl)phenyl]pyrrolidin-3-yl}carbonyl)-4-phenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-cyclopropyl-4-phenylpiperidine;

(2S,4S)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-(2-cyclopropylphenyl)-2-phenylpiperidine;

1-{[(3S,4R)-4-methyl-4-phenylpyrrolidin-3-yl]carbonyl}-4-phenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-isopropyl-4-phenylpiperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-4-methyl-2-phenylpiperidine;

4-phenyl-1-{[(3S,4R)-4-phenylpyrrolidin-3-yl]carbonyl}piperidine;

1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-phenyl-4-propylpiperidine;

(2S,4R)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-methyl-4-phenylpiperidine;

2-isopropyl-1-({(3S,4R)-4-[4′-(methylsulfonyl)biphenyl-2-yl]pyrrolidin-3-yl}carbonyl)-4-phenylpiperidine;

2-isopropyl-4-phenyl-1-{[(3S,4R)-4-phenylpyrrolidin-3-yl]carbonyl}piperidine;

3-((2R,4S)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-phenylpiperidin-4-yl)pyridine;

(2R,4R)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-methyl-4-phenylpiperidine;

2-((2R,4S)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-phenylpiperidin-4-yl)pyridine;

(2S,4S)-1-{[(3S,4R)-4-methyl-4-phenylpyrrolidin-3-yl]carbonyl}-2,4-diphenylpiperidine;

(3S)-4-{[(3 S,4R)-4-methyl-4-phenylpyrrolidin-3-yl]carbonyl}-3-phenylmorpholine;

2-cyclopropyl-1-{[(3S,4R)-4-methyl-4-phenylpyrrolidin-3-yl]carbonyl}-4-phenylpiperidine;

2-isopropyl-1-{[(3S,4R)-4-methyl-4-phenylpyrrolidin-3-yl]carbonyl}-4-phenylpiperidine;

(2S,4S)-1-{[(3 S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-isopropyl-4-phenylpiperidine;

(2S,4S)-1-{[(3S,4R)-4-(2-bromophenyl)pyrrolidin-3-yl]carbonyl}-2-methyl-4-phenylpiperidine;

N,N-dimethyl-4-{(3R,4S)-4-[(4-phenylpiperidin-1-yl)carbonyl]pyrrolidin-3-yl}aniline;

or a pharmaceutically acceptable salt thereof.

14. A pharmaceutical composition comprising a compound of any of claims 1 - 13 , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.