| 主权项 |
1. A compound of the formula wherein R1 is selected from the group consisting of C1-6 alkyl, halo, cyano, C1-6 hydroxyalkyl, R2 is (i)aryl (ii)heteroaryl said aryl or heteroaryl optionally substituted by one or three groups independently selected from C1-6 alkyl, C1-6 alkoxy, C1-6 haloalkyl or halogen and said heteroaryl is pyridinyl, (iii) piperazinyl or (iv) piperidinyl said piperazinyl or piperidinyl optionally substituted by aryl which aryl is optionally substituted as described above; or, a pharmaceutically acceptable salt thereof. |
