abstract |
A compound of formula (I): or a pharmaceutically acceptable salt thereof, wherein: R 1 is selected from the group consisting of C 1-6 alkyl, C 1-6 alkoxy, 3-5-membered carbocyclyl and N , N- (C1-6 alkyl) 2-amino, wherein R1 may be optionally substituted on a carbon with one or more R6; R2 is selected from the group consisting of hydrogen, halo, nitro and C1-6 alkyl, wherein R2 may be optionally substituted on a carbon with one or more R8; R3 is selected from the group consisting of hydrogen, fluoro, chloro, bromo, N-methyl-N-mesylamino and morpholino; R4 is C1-6 alkyl; R5 it is halo; R6 is halo; R8 is halo; and n> = 1. |