Patent ID: 7829555

Claim:
A bioreductive conjugate of the formula II: (wherein R 1 and R 2 independently represent hydrogen or halogen atoms, or a group R, OR, SR, NHR, NR 2 , CO 2 R or CONHR; or, alternatively, R 1 and R 2 together with the intervening ring carbon atoms form a 5-7 membered carbocyclic or heterocyclic ring itself optionally substituted by one or more halogen atoms, or by one or more groups selected from R, OR, SR, NHR, NR 2 , CO 2 R and CONHR; Z represents an alkyl, alkenyl, aryl or aralkyl group optionally carrying at least one OH, SH, NH 2 or NHR 7 group in which R 7 is an alkyl group or Z represents a group of the formula —XH where X represents an oxygen or a sulphur atom, or a group of formula NY in which Y represents a hydrogen atom or an alkyl group; R 3 , R 4 , R 5 and R 6 independently represent hydrogen atoms or an alkyl or alkenyl group; each group R independently represents a hydrogen atom, an alkyl or alkenyl group; E represents the residue of a therapeutic agent to be delivered, optionally attached via a linking group L which is an ester, phosphate ester, ether, amine, thiol or thiol ester group or any combination thereof; m=0, 1, 2 or 3; and p=0 or 2; with the proviso that when m=1 then p=0) or a salt thereof.