| abstract |
A compound of formula (I) or a pharmaceutically acceptable salt thereof ** (See formula) ** in which: R 1 is hydrogen or C 1-3 alkyl and R 2 is selected from C 1-6 alkyl; and - C2-6 alkyl substituted with hydroxy, C1-4 alkoxy or an NRaRb group in which Ra and Rb are independently hydrogen or C1-4 alkyl, or Ra and Rb combine together with the N to which they are attached to form a heterocyclyl ring; or R1 and R2 combine together with the N to which they are attached to form a heterocyclyl ring; R3 is hydrogen, C1-3 alkyl or CH2OH; R4 is selected from - a phenyl group optionally substituted with C1-4 alkyl, CF3, halogen, hydroxy or C1-4 alkoxy; - a heteroaromatic group optionally substituted with C1-4 alkyl, CF3, halogen, hydroxy or C1-4 alkoxy; - a tetrahydropyranyl group; - a tetrahydrofuranyl group; - a C3-7 cycloalkyl group; and - a CH2OMe group. |