abstract |
A compound of Formula I: ** (See formula) ** wherein: R1 is hydrogen, NH2 or fluoro; R2 and R3 are methyl or hydrogen; or R2 is methyl, ethyl, 1-hydroxyethyl, 1-methoxyethyl, fluoromethyl, 1-fluoroethyl or 1-methylethyl, and R3 is hydrogen; R4 is methyl or fluoromethyl; R5 is hydrogen, ethyl or -CH2-cyclopropyl, or a pharmaceutically acceptable salt thereof. |