| abstract |
The present invention provides a compound of formula I, wherein A is selected from the group consisting of: □R1 is H or F; R2 is H, -CH2OH, C1-C3 alkyl, □R3 is H, F or CN; R4 is H And F or CN; and R5 is H, -CH3 or -OCH3; or a pharmaceutically acceptable salt thereof. |