Synthesis of selenophene derivatives as novel CHK1 inhibitors.

A series of selenophene derivatives 3 were synthesized as potential CHK1 inhibitors. The effects of substitution on the 4'- or 5'-position of selenophene moiety and shifting the hydroxyl group position on C6- phenolic ring of oxindole were explored. This study led to the discovery of the most potent CHK1 inhibitors 29-33 and 39-43, which had IC(50) values in the subnanomolar range.