Fused bicyclic aromatic compounds that are useful in treating sexual dysfunction

1. A compound of formula (II)

or a pharmaceutically acceptable salt thereof, wherein

X is selected from the group consisting of CR X and N;

Y is selected from the group consisting of O, and S;

V is selected from the group consisting of CR V and N;

P is selected from the group consisting of CR P and N;

Q is selected from the group consisting of CRC Q and N;

S is selected from the group consisting of CR S and N;

T is selected from the group consisting of CR T and N;

provided that 1 of P, Q, S, and T is N;

further provided that when only T is N, and or V is CR V , then Y cannot be O;

R P , R Q , R S , R T , R V , and R X are independently selected from the group consisting of hydrogen, alkoxy, alkenyl, alkyl, alkylsulfinyl, alkylsulfonyl, alkylthio, alkynyl, alkoxycarbonyl, alkylcarbonyl, alkylcarbonyloxy, carboxy, cyano, formyl, halogen, haloalkoxy, haloalkyl, hydroxy, hydroxyalkyl, mercapto, nitro, —NZ 1 Z 2 , (NZ 3 Z 4 )carbonyl, and (NZ 3 Z 4 )sulfonyl;

Z 1 and Z 2 are each independently selected from the group consisting of hydrogen, alkyl, alkylcarbonyl, alkylsulfonyl, aryl, arylalkyl, arylalkylsulfonyl, arylsulfonyl, and formyl;

Z 3 and Z 4 are each independently selected from the group consisting of hydrogen, alkyl, aryl, and arylalkyl;

L is alkylene;

D is selected from the group consisting of

wherein the left end is attached to L and the right end is attached to B 1 ;

R A is selected from the group consisting of hydrogen and alkyl;

Z is selected from the group consisting of N;

— is absent;

B 1 is selected from the group consisting of

R 1 , R 2 , R 3 , R 4 and R 5 are each independently selected from the group consisting of hydrogen, alkoxy, alkenyl, alkyl, alkylsulfinyl, alkylsulfonyl, alkylthio, alkynyl, alkoxycarbonyl, alkylcarbonyl, alkylcarbonyloxy, carboxy, cyano, formyl, halogen, haloalkoxy, haloalkyl, hydroxy, hydroxyalkyl, mercapto, nitro, —NZ 1 Z 2 , (NZ 3 Z 4 )carbonyl, and (NZ 3 Z 4 )sulfonyl;

X 1 is selected from the group consisting of N(R 6 ), O and S;

Y 1 is selected from the group consisting of C(R 7 ) and N;

R 6 is selected from the group consisting of hydrogen and alkyl; and

R 7 is selected from the group consisting of hydrogen and alkyl.

2. The compound according to claim 1 wherein

A is

P is N;

Q is CR Q ;

S is CR S ;

T is CR T ;

X is CR X ; and

Y is selected from the group consisting of O and S.

3. The compound according to claim 1 wherein

P is N;

Q is CR Q ;

S is CR S ;

T is CR T ;

X is CR X ;

Y is selected from the group consisting of O and S;

4. The compound according to claim 3 wherein

R Q , R S , R T , and R X are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

Z is N;

— is absent; and

R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkoxy, alkyl, alkylthio, cyano, and halogen.

5. The compound according to claim 4 selected from the group consisting of

2-{[4-(3-methyl-2-pyridinyl)-1-piperazinyl]methyl}furo[3,2-b]pyridine;

2-[4-(furo[3,2-b]pyridin-2-ylmethyl)-1-piperazinyl]nicotinonitrile; and

2-{[4-(2-pyridinyl)-1-piperazinyl]methyl}furo[3,2-b]pyridine.

6. The compound according to claim 1 wherein

P is N;

Q is CR Q ;

S is CR S ;

T is CR T ;

X is CR X ;

Y is selected from the group consisting of O and S;

7. The compound according to claim 6 wherein

R Q , R S , R T , and R X are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

Z is N;

— is absent; and

R 1 , R 2 , R 3 , R 4 , and R 5 are independently selected from the group consisting of hydrogen, alkoxy, alkyl, alkylthio, cyano, halogen, and hydroxy.

8. The compound according to claim 7 selected from the group consisting of

4-(4-{[6-(trifluoromethyl)thieno[3,2-b]pyridin-2-yl]methyl}-1-piperazinyl)phenol;

2-{[4-(2-methoxyphenyl)-1-piperazinyl]methyl}-6-(trifluoromethyl)thieno[3,2-b]pyridine;

2-(4-{[6-(trifluoromethyl)thieno[3,2-b]pyridin-2-yl]methyl}-1-piperazinyl)benzonitrile;

4-[4-(furo[3,2-b]pyridin-2-ylmethyl)-1-piperazinyl]phenol;

2-[(4-phenyl-1-piperazinyl)methyl]furo[3,2-b]pyridine;

2-{[4-(2-methoxyphenyl)-1-piperazinyl]methyl}furo[3,2-b]pyridine;

2-[4-(furo[3,2-b]pyridin-2-ylmethyl)-1-piperazinyl]benzonitrile; and

2-{[4-(2-fluorophenyl)-1-piperazinyl]methyl}furo[3,2-b]pyridine.

9. The compound according to claim 1 wherein

P is N;

Q is CR Q ;

S is CR S ;

T is CR T ;

X is N;

Y is selected from the group consisting of O and S;

10. The compound according to claim 9 wherein

R Q , R S , and R T are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

Z is N;

— is absent; and

R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkoxy, alkyl, alkylthio, cyano, and halogen.

11. The compound according to claim 1 wherein

P is N;

Q is CR Q ;

S is CR S ;

T is CR T ;

X is N;

Y is selected from the group consisting of O and S;

12. The compound according to claim 11 wherein

R Q , R S , and R T are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

Z is N;

— is absent; and

R 1 , R 2 , R 3 , R 4 , and R 5 are independently selected from the group consisting of hydrogen, alkoxy, alkyl, alkylthio, cyano, halogen, and hydroxy.

13. The compound according to claim 12 selected from the group consisting of

2-{[4-(2-methoxyphenyl)-1-piperazinyl]methyl}[1,3]oxazolo[4,5-b]pyridine; and

2-[4-([1,3]oxazolo[4,5-b]pyridin-2-ylmethyl)-1-piperazinyl]benzonitrile.

14. The compound according to claim 1 wherein

P is CR P ;

Q is CR Q ;

S is CR S ;

T is N;

X is N;

Y is selected from the group consisting of O and S;

15. The compound according to claim 14 wherein

R P , R Q , and R S are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

Z is N;

— is absent; and

R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkoxy, alkyl, alkylthio, cyano, and halogen.

16. The compound according to claim 15 selected from the group consisting of

5-methoxy-2-{[4-(6-methyl-2-pyridinyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine;

5-methoxy-2-{[4-(2-pyridinyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine;

2-{[4-(6-methyl-2-pyridinyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine;

2-[4-([1,3]thiazolo[5,4-b]pyridin-2-ylmethyl)-1-piperazinyl]nicotinonitrile; and

2-{[4-(2-pyridinyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine.

17. The compound according to claim 1 wherein

P is CR P ;

Q is CR Q ;

S is CR S ;

T is N;

X is N;

Y is selected from the group consisting of O and S;

18. The compound according to claim 17 wherein

R P , R Q , and R S are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

Z is N;

— is absent; and

R 1 , R 2 , R 3 , R 4 , and R 5 are independently selected from the group consisting of hydrogen, alkoxy, alkyl, alkylthio, cyano, halogen, and hydroxy.

19. The compound according to claim 18 selected from the group consisting of

4-{4-[(5-methoxy[1,3]thiazolo[5,4-b]pyridin-2-yl)methyl]-1-piperazinyl}phenol;

2-{[4-(2-fluorophenyl)-1-piperazinyl]methyl}-5-methoxy[1,3]thiazolo[5,4-b]pyridine;

5-methoxy-2-({4-[2-(methylthio)phenyl]-1-piperazinyl}methyl)[1,3]thiazolo[5,4-b]pyridine;

5-methoxy-2-{[4-(2-methoxyphenyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine;

2-{[4-(2-chlorophenyl)-1-piperazinyl]methyl}-5-methoxy[1,3]thiazolo[5,4-b]pyridine;

2-{4-[(5-methoxy[1,3]thiazolo[5,4-b]pyridin-2-yl)methyl]-1-piperazinyl}benzonitrile;

2-{[4-(2-chlorophenyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine;

2-{[4-(5-chloro-2-methoxyphenyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine;

4-[4-([1,3]thiazolo[5,4-b]pyridin-2-ylmethyl)-1-piperazinyl]phenol;

2-({4-[2-(methylthio)phenyl]-1-piperazinyl}methyl)[1,3]thiazolo[5,4-b]pyridine;

2-{[4-(2-fluorophenyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine;

2-[4-([1,3]thiazolo[5,4-b]pyridin-2-ylmethyl)-1-piperazinyl]benzonitrile;

2-{[4-(2-methoxyphenyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine; and

2-[(4-phenyl-1-piperazinyl)methyl][1,3]thiazolo[5,4-b]pyridine.

20. The compound according to claim 1 wherein

P is CR P ;

Q is CR Q ;

S is CR S ;

T is N;

X is N;

Y is selected from the group consisting of O and S;

21. The compound according to claim 20 wherein

R P , R Q , and R S are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

Z is N;

— is absent; and

R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkyl, and halogen.

22. The compound according to claim 21 selected from the group consisting of

5-methoxy-2-{[4-(2-pyrimidinyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine; and

2-{[4-(2-pyrimidinyl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine.

23. The compound according to claim 1 wherein

P is CR P ;

Q is CR Q ;

S is CR S ;

T is N;

X is N;

Y is selected from the group consisting of O and S;

24. The compound according to claim 23 wherein

R P , R Q , and R S are independently selected from the group consisting of hydrogen, alkoxy, alkyl, haloalkyl, and halogen;

X 1 is S;

Y 1 is N; p 1 Z is N;

— is absent; and

R 2 , and R 3 are independently selected from the group consisting of hydrogen, alkyl, and halogen.

25. The compound according to claim 24 that is 2-{[4-(1,3-thiazol-2-yl)-1-piperazinyl]methyl}[1,3]thiazolo[5,4-b]pyridine.