Compounds having the structural formula I or a pharmaceutically acceptable salt thereof, wherein: X 1 and X 2 are 1-3 substituents independently selected from the group consisting of H, alkyl, halo, —CF 3 , —OCF 3 , alkoxy, —OH and —CN; n is 0, 1 or 2; and R and R 1 are H or alkyl; also disclosed is the use of the compounds in the treatment of CNS diseases such as Parkinson's disease, alone or in combination with other agents for treating CNS diseases, pharmaceutical compositions comprising them and kits comprising the components of the combinations.
1. A compound represented by the structural formula
or a pharmaceutically acceptable salt thereof, wherein:
X 1 is 1-3 substituents independently selected from the group consisting of H, alkyl, halo, —CF 3 , —OCF 3 , alkoxy, —OH and —CN;
X 2 is 1-3 substituents independently selected from the group consisting of H, alkyl, halo, —CF 3 , —OCF 3 , alkoxy, —OH and —CN;
n is 0, 1 or 2; and
R and R 1 are independently selected from the group consisting of H and alkyl.
2. A compound of claim 1 wherein n is 1.
3. A compound of claim 1 wherein R and R 1 are each H.
4. A compound of claim 1 wherein X 1 is 1 or 2 substituents independently selected from H, halo, alkyl, alkoxy and —CF 3 .
5. A compound of claim 4 wherein X 1 is 1 or 2 substituents independently selected from H, fluoro, chloro, methyl, methoxy and —CF 3 .
6. A compound of claim 1 wherein X 2 is 1, 2 or 3 substituents independently selected from H, halo, alkyl, alkoxy, —CF 3 , —OCF 3 and —CN.
7. A compound of claim 6 wherein X 2 is 1, 2 or 3 substituents independently selected from H, fluoro, chloro, methyl, methoxy, —CF 3 , —OCF 3 and —CN.
8. A compound of claim 1 wherein n is 1; R and R 1 are each H; X 1 is 1 or 2 substituents independently selected from H, halo, alkyl, alkoxy and —CF 3 ; and X 2 is 1, 2 or 3 substituents independently selected from H, halo, alkyl, alkoxy, —CF 3 , —OCF 3 and —CN.
9. A compound of claim 8 wherein X 1 is 1 or 2 substituents independently selected from H, fluoro, chloro, methyl, methoxy and —CF 3 , and X 2 is 1, 2 or 3 substituents independently selected from H, fluoro, chloro, methyl, methoxy, —CF 3 , —OCF 3 and —CN.
10. A compound of claim 1 selected from the group consisting of
11. A pharmaceutical composition comprising a therapeutically effective amount of a compound of claim 1 in a pharmaceutically acceptable carrier.
12. A pharmaceutical composition comprising a therapeutically effective amount of a combination of a compound of claim 1 and one to three other agents useful in treating Parkinson's disease in a pharmaceutically acceptable carrier.
13. A kit comprising in separate containers in a single package pharmaceutical compositions for use in combination to treat Parkinson's disease wherein one container comprises a pharmaceutical composition comprising an effective amount of a compound of claim 1 in a pharmaceutically acceptable carrier, and wherein, in separate containers, one or more pharmaceutical compositions each comprise an effective amount of an agent useful in the treatment of Parkinson's disease in a pharmaceutically acceptable carrier.