Modulators of G protein-coupled receptor 88

1. A compound of formula (II)

or a pharmaceutically acceptable salt thereof, wherein

A is selected from pyrazinyl and pyridinyl;

R 1 is selected from:

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

R 3 is selected from C 4 alkyl and C 1 alkoxy-C 2 alkyl;

R 4 is hydrogen; or

R 3 and R 4 , together with the carbon atom to which they are attached, form a carbonyl group, or form a ring selected from C 5 cycloalkyl and tetrahydropyranyl;

R 6 is selected from hydrogen and halo; and

R 7 is selected from

C 5 alkynyl;

C 3 cycloalkyl;

C 4 cycloalkyl-C 1 alkoxy; and

phenyl optionally substituted with one substituent selected from C 3 alkoxy, C 1 alkoxy-C 1 alkyl, C 3 alkyl, and C 2 alkynyl, provided that when the phenyl is substituted the substituent is in the para position on the phenyl ring;

R 8 is selected from hydrogen; C 1 -C 3 alkyl; and halo; and

R 9 is selected from hydrogen; C 1 -C 3 alkyl; and halo.

2. A compound selected from

or a pharmaceutically acceptable salt thereof.

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

4. A method of modulating G protein-coupled receptor 88 in a mammal, comprising administering to the mammal a therapeutically effective amount of a compound of claim 1 , or a pharmaceutically acceptable salt thereof.

5. The method of claim 4 wherein the mammal is a human.

6. The method of claim 4 wherein the G protein-coupled receptor 88 is modulated in order to treat a neurological disorder.

7. The method of claim 6 wherein the G protein-coupled receptor 88 is modulated in order to treat a neurological disorder wherein the neurological disorder is selected from psychosis, cognitive deficits in schizophrenia, affective disorders, attention deficit hyperactivity disorders, bipolar disorder, drug addiction, Parkinson's disease, and Alzheimer's disease.