Therapeutic agents useful for treating pain

1. A compound of formula:

or a pharmaceutically acceptable salt thereof, wherein:

Ar 1 is

X is O or S;

R 1 is -halo, —CH 3 , —C(halo) 3 , —CH(halo) 2 , or —CH 2 (halo);

each R 2 is independently:

(a) -halo, —OH, —NH 2 , —CN, or —NO 2 ;

(b) —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups; or

(c) -phenyl, -naphthyl, —(C 14 )aryl, or -(5- to 10-membered)heteroaryl, each of which is unsubstituted or substituted with one or more R 6 groups;

each R 3 is independently:

(a) -halo, —CN, —OH, —NO 2 , or —NH 2 ;

(b) —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups; or

(c) -phenyl, -naphthyl, —(C 1-4 )aryl, or -(5- to 10-membered)heteroaryl, each of which is unsubstituted or substituted with one or more R 6 groups;

each R 5 is independently —CN, —OH, —(C 1 -C 6 )alkyl, —(C 2 -C 6 )alkenyl, -halo, —N 3 , —NO 2 , —N(R 7 ) 2 , —CH═NR 7 , —NR 7 OH, —OR 7 , —COR 7 , —C(O)OR 7 , —OC(O)R 7 , —OC(O)OR 7 , —SR 7 , —S(O)R 7 , or —S(O) 2 R 7 ;

each R 6 is independently —(C 1 -C 6 )alkyl, —(C 2 -C 6 )alkenyl, —(C 2 -C 6 )alkynyl, —(C 3 -C 8 )cycloalkyl, —(C 5 -C 8 )cycloalkenyl, -phenyl, -(3- to 5-membered)heterocycle, —C(halo) 3 , —CH(halo) 2 , —CH 2 (halo), —CN, —OH, -halo, —N 3 , —NO 2 , N(R 7 ) 2 , —CH═NR 7 , —NR 7 OH, —OR 7 , —COR 7 , —C(O)OR 7 , —OC(O)R 7 , —OC(O)OR 7 , —SR 7 , —S(O)R B , or —S(O) 2 R 7 ;

each R 7 is independently —H, —(C 1 -C 6 )alkyl, —(C 2 -C 6 )alkenyl, —(C 2 -C 6 )alkynyl, —(C 3 -C 8 )cycloalkyl, —(C 5 -C 8 )cycloalkenyl, -phenyl, -(3- to 5-membered)heterocycle, —C(halo) 3 , —CH(halo) 2 , or —CH 2 (halo);

each R 8 is independently —(C 1 -C 6 )alkyl, —(C 2 -C 6 )alkenyl, —(C 2 -C 6 )alkynyl, —(C 3 -C 8 )cycloalkyl, —(C 5 -C 8 )cycloalkenyl, -phenyl, —C(halo) 3 , —CH(halo) 2 , —CH 2 (halo), —CN, —OH, -halo, —N 3 , —NO 2 , —N(R 7 ) 2 , —CH═NR 7 , —NR 7 OH, —OR 7 , —COR 7 , —C(O)OR 7 , —OC(O)R 7 , —OC(O)OR 7 , —SR 7 , —S(O)R 7 , or —S(O) 2 R 7 ;

each R 11 is independently —(C 1 -C 6 )alkyl, —(C 2 -C 6 )alkenyl, —(C 2 -C 6 )alkynyl, —(C 3 -C 8 )cycloalkyl, —(C 5 -C 8 )cycloalkenyl, -phenyl, —C(halo) 3 , —CH(halo) 2 , —CH 2 (halo), —CN, —OH, -halo, —N 3 , —NO 2 , —N(R 7 ) 2 , —CH═NR 7 , —NR 7 OH, —OR 7 , —COR 7 , —C(O)OR 7 , —OC(O)R 7 , —OC(O)OR 7 , —SR 7 , —S(O)R 7 , or —S(O) 2 R 7 ;

each halo is independently —F, —Cl, —Br, or —I;

m is an integer ranging from 0 to 4;

o is an integer ranging from 0 to 4;

p is an integer ranging from 0 to 2;

q is an integer ranging from 0 to 6;

r is an integer ranging from 0 to 5; and

s is an integer ranging from 0 to 4.

2. The compound of claim 1 , wherein p is 1 and R 2 is —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups.

3. The compound of claim 2 , wherein R 2 is —(C 1 -C 10 )alkyl which is substituted with two R 5 groups.

4. The compound of claim 1 , wherein:

Ar 2 is

X is O; and

R 1 is —F, —Cl, —CH 3 , or —CF 3 .

5. The compound of claim 4 , wherein p is 1 and R 2 is —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups.

6. The compound of claim 5 , wherein R 2 is —(C 1 -C 10 )alkyl which is substituted with two R 5 groups.

7. The compound of claim 4 , wherein:

m is 0;

r is 1; and

R 8 is —(C 1 -C 6 )alkyl, -halo, —OCF 3 , or —CF 3 .

8. The compound of claim 7 , wherein p is 1 and R 2 is —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups.

9. The compound of claim 8 , wherein R 2 is —(C 1 -C 10 )alkyl which is substituted with two R 5 groups.

10. The compound of claim 7 , wherein the —(C 1 -C 6 )alkyl is a tert-butyl group, optionally substituted at the 4-position of Ar 2 .

11. The compound of claim 1 , wherein:

Ar 2 is

X is O;

R 1 is —CH 3 , —CF 3 , —Cl, —Br, —I, or —F;

m is 0;

(R 8 ) a is —H; and

(R 8 ) b is —H, —CH 3 , —OCH 3 , —CF 3 , —OCF 3 , —OCH 2 CH 3 , iso-propyl, tert-butyl, —Cl, —Br, —I, or —F.

12. The compound of claim 11 , wherein p is I and R 2 is —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups.

13. The compound of claim 12 , wherein R 2 is —(C 1 -C 10 )alkyl which is substituted with two R 5 groups.

14. The compound of claim 11 , wherein R 1 is —CH 3 , —CF 3 , or —Cl and (R 8 ) b is —Cl, —F, —CF 3 , —OCF 3 , or tent-butyl.

15. The compound of claim 1 , wherein:

Ar 2 is

X is O; and

R 1 is —F, —Cl, —CH 3 or —CF 3 .

16. The compound of claim 15 , wherein p is 1 and R 2 is —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups.

17. The compound of claim 16 , wherein R 2 is —(C 1 -C 10 )alkyl which is substituted with two R 5 groups.

18. The compound of claim 15 , wherein:

m is 0;

o is 1; and

R 8 is —(C 1 -C 6 )alkyl or -halo.

19. The compound of claim 18 , wherein p is 1 and R 2 is —(C 1 -C 10 )alkyl, —(C 2 -C 10 )alkenyl, —(C 2 -C 10 )alkynyl, —(C 3 -C 10 )cycloalkyl, —(C 8 -C 14 )bicycloalkyl, —(C 8 -C 14 )tricycloalkyl, —(C 5 -C 10 )cycloalkenyl, —(C 8 -C 14 )bicycloalkenyl, —(C 8 -C 14 )tricycloalkenyl, -(3- to 7-membered)heterocycle, or -(7- to 10-membered)bicycloheterocycle, each of which is unsubstituted or substituted with one or more R 5 groups.

20. The compound of claim 19 , wherein R 2 is —(C 1 -C 10 )alkyl which is substituted with two R 5 groups.

21. A composition comprising an effective amount of the compound or a pharmaceutically acceptable salt of the compound of claim 1 and a pharmaceutically acceptable carrier or excipient.

22. An in vitro method for inhibiting VR1 function in a cell comprising:

contacting a cell expressing VR1 in vitro with a compound of claim 1 , or a pharmaceutically acceptable salt thereof, in an amount sufficient to reduce calcium ion mobilization into said cell treated with an activator of VR1 as compared to said cell expressing VR1 in vitro treated with an activator of VR1 and not contacted with said compound.

23. A method for treating pain in an animal, comprising administering to an animal in need thereof an effective amount of the compound or a pharmaceutically acceptable salt of the compound of claim 1 .