Abstract: The present invention relates to a series of CDK-inhibiting purine derivatives of structural formula (I), or a pharmaceutically acceptable salt and/or prodrug form thereof, wherein: X is O, S or CHRX where RX is H or C1-14 alkyl; D is NZ1Z2 where Z1 is selected from H, C1-4 alkyl, C1-4 hydroxyalkyl, an unsubstituted or substituted aryl or heteroaryl, and an unsubstituted or substituted aralkyl or heteroaralkyl group, and Z2 is selected from an unsubstituted or substituted aryl or heteroaryl, and an unsubstituted or substituted aralkyl or heteroaralkyl group; A is selected from H, C1-4 alkyl, C1-4 alkoxy, hydroxy, CH2(CH2)nOH (n=1-4), and NRa1Ra2 where Ra1 and Ra2 are each independently H or C1-4 alkyl; B is selected from H, halo, C1-4 alkyl, C1-4 alkoxy, CF3, an optionally substituted aryl or an optionally substituted aralkyl, and a hydroxy group that may undergo a C═O tautomeric rearrangement; and Y comprises an unsubstituted or substituted 4- to 8-membered carbocyclic or heterocyclic ring, optio

Abstract: A pyrimidine derivative of formula (I) wherein, for example, R1 is-(1-6C)alkyl or (3-5C)alkenyl [optionally substituted by a phenyl substituent]; Q1 and Q2 are independently selected from phenyl, naphthyl, indanyl and 1,2,3,4-tetrahydronaphthyl; and one or both of Q1 and Q2 bears one substituent of formula (Ia) [provided that when present in Q1 the substituent of formula (Ia) is not adjacent to the —NH-link]; wherein, for example, X is CH2, O, S or NH; Y is H or as defined for Z; Z is OH, SH, NH2, (1-4C)alkoxy, (1-4C)alkylthio, —NH(1-4C)alkyl, —N[(1-4C)alkyl]2 or —NH-(3-8C)cycloalkyl; n is 1, 2 or 3; m is 1, 2 or 3; and Q1 and Q2 may each optionally bear other substituents selected from halogeno, (1-6C)alkyl, cyano and (2-4C)alkenyl, or a pharmaceutically-acceptable salt, or in-vivo-hydrolysable ester thereof; are useful as anti-cancer agents; and processes for their manufacture and pharmaceutical compositions containing them are describe