Modulators of G protein-coupled receptor 88

1. A compound of Formula (I)

or a pharmaceutically acceptable salt thereof, wherein

A is selected from phenyl and thienyl;

R 1 is selected from C 2 -C 6 alkenyl; C 3 -C 6 alkoxy; C 3 -C 6 alkylsulfanyl; C 2 -C 6 alkynyl; C 3 -C 6 cycloalkyl-C 2 -C 4 alkenyl; C 3 -C 6 cycloalkyl-C 1 -C 3 alkoxy; C 3 -C 6 cycloalkyloxy; phenoxy optionally substituted with one C 1 -C 3 alkyl group; phenyl optionally substituted with one, two, or three groups independently selected from C 1 -C 3 alkoxy, C 1 -C 3 alkoxy-C 1 -C 3 alkyl, C 1 -C 3 alkyl, C 1 -C 3 alkylsulfonyl, cyano, halo, and halo-C 1 -C 3 alkyl; phenyl-C 1 -C 3 alkoxy wherein the phenyl part is optionally substituted with one or two groups independently selected from C 1 -C 3 alkyl and halo; and thienyl;

R 2 is selected from hydrogen; C 1 -C 3 alkoxy; C 1 -C 3 alkyl; and halo;

R 3 is selected from hydrogen and C 1 -C 3 alkoxy;

R 4 is selected from C 1 -C 3 alkoxy-C 1 -C 3 alkyl; C 1 -C 6 alkyl; heterocyclyl; hydroxy-C 1 -C 3 alkyl; (R a R b N)—C 1 -C 3 alkyl;

wherein denotes the point of attachment to the parent molecular moiety;

R 5 is hydrogen; and

R a and R b are independently selected from hydrogen and C 1 -C 3 alkyl; or

R a and R b , together with the nitrogen atom to which they are attached, form a piperidinyl or piperazinyl ring wherein each ring is optionally substituted with one group selected from C 1 -C 3 alkyl and hydroxy-C 1 -C 3 alkyl.

2. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 3 is hydrogen.

3. The compound of claim 2 , or a pharmaceutically acceptable salt thereof, wherein A is phenyl.

4. The compound of claim 3 , or a pharmaceutically acceptable salt thereof, wherein R 4 is selected from C 1 -C 3 alkoxy-C 1 -C 3 alkyl; hydroxy-C 1 -C 3 alkyl; and

5. The compound of claim 3 , or a pharmaceutically acceptable salt thereof, wherein R 4 is selected from C 1 -C 6 alkyl and

6. The compound of claim 3 , or a pharmaceutically acceptable salt thereof, wherein R 4 is heterocyclyl.

7. The compound of claim 3 , or a pharmaceutically acceptable salt thereof, wherein R 4 is (R a R b N)—C 1 -C 3 alkyl.

8. The compound of claim 2 , or a pharmaceutically acceptable salt thereof, wherein A is thienyl.

9. The compound of claim 8 , or a pharmaceutically acceptable salt thereof, wherein R 4 is selected from C 1 -C 3 alkoxy-C 1 -C 3 alkyl; hydroxy-C 1 -C 3 alkyl; and

10. The compound of claim 8 , or a pharmaceutically acceptable salt thereof, wherein R 4 is selected from C 1 -C 6 alkyl and

11. The compound of claim 8 , or a pharmaceutically acceptable salt thereof, wherein R 4 is heterocyclyl.

12. The compound of claim 8 , or a pharmaceutically acceptable salt thereof, wherein R 4 is (R a R b N)—C 1 -C 3 alkyl.

13. A compound of Formula (II)

or a pharmaceutically acceptable salt thereof, wherein

A is selected from phenyl and thienyl;

R 1 is selected from C 5 -C 6 alkoxy; C 5 alkynyl; phenyl optionally substituted with one group selected from C 1 alkoxy and C 1 -C 2 alkyl;

R 2 is selected from hydrogen; C 1 alkoxy and C 1 alkyl;

R 4 is selected from hydroxy-C 1 alkyl and (R a R b N)—C 1 alkyl; and

R a and R b are each hydrogen; or

R a and R b , together with the nitrogen atom to which they are attached, form a piperazinyl ring substituted with one C 1 alkyl group.

14. A compound selected from

15. A composition comprising a compound of claim 1 , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.