A new series of potent oxindole inhibitors of CDK2

A novel series of oxindole-type inhibitors of CDK2 that have heteroatom substituted alkynyl moieties at their C-4 position is described. These novel 4-alkynyl-substituted inhibitors have superior potency relative to their parent compound in free enzyme and in cell based assays. The crystal structure of CDK2 in complex with one of these analogues was determined and gives insight to their increased potency. The biochemical evaluation of a representative derivative is also described.     

Synthesis of potent oxindole CDK2 inhibitors

A series of oxindole CDK2 inhibitors was synthesized. These novel analogues have a saturated monosubstituted cyclic moiety at their C-4 position that mimics the ribofuranoside of ATP. This substitution afforded agents with increased potency relative to the parent indolinone and nanomolar range IC(50) against the CDK2 enzyme and two cancer cell lines.     

3,5,6-Trisubstituted naphthostyrils as CDK2 inhibitors

A novel class of 3,5,6-trisubstituted naphthostyril analogues was designed and synthesized to study the structure-activity relationship for inhibition of cyclin-dependent kinase 2 (CDK2). These compounds, particularly molecules with side-chain modifications providing additional hydrogen bonding capability, were demonstrated to be potent CDK2 inhibitors with cellular activities consistent with CDK2 inhibition. These molecules inhibited tumor cell proliferation and G1-S and G2-M cell-cycle progression in vitro. The X-ray crystal structure of a 2-aminoethyleneamine derivative bound to CDK2, refined to 2.5A resolution, is presented.