| abstract |
The invention provides compounds of general formula (I), wherein: X is halogen or OSO2R, where R represents H or is unsubstituted or hydroxy- or amino--substituted lower alkyl; Y is a nitro or amine group or a substituted derivative thereof; W is selected from the structures of formulae (Ia, Ib or Ic), where E is N- or -CH-, G is 0, S, or NH, and Q is either up to three of R, OR, NRR, NO2, CONHR, NHCOR or NHCONHR, or is an additional group of formulae (Ia, Ib or Ic) and HET represents a 5- or 6-membered carbocycle or heterocycle; and A and B collectively represent a fused benzene or 2--CO2R pyrrole ring. In one embodiment, the group Y is an amine derivative substituted by a group which is a substrate for a nitroreductase or carboxypeptidase enzyme such that one of said enzymes is able to bring about removal of that group. |