Abstract: This invention relates to compounds of formula (1) wherein B is optionally substituted aryl; R1 and R2 are the same or different and are independently selected from hydrogen or C1-3 alkyl; n is 1 or 2, preferably n is 1; m is 0 or 1; R3 is hydrogen or acyl; R4 and R5 are the same or different and are independently selected from amino, alkylamino, dialkylamino, arylamino and C2-C8 cycloalkylamino; X and Y are independently selected from C, H or N provided at least one of X and Y is N; and salts thereof, solvates thereof, pharmaceutically acceptable derivatives thereof, prodrugs thereof, tautomers thereof and/or isomers thereof; and processes for their preparation and methods of treatment, pharmaceutical formulations and uses involving them.