Synthesis and biological evaluation of highly potent analogues of epothilones B and D

A series of new epothilone B and D analogues incorporating fused hetero-aro matic side chains have been prepared. The synthetic strategy is based on ol efin 3 as the common intermediate and allows variation of the side-chain st ructure in a highly convergent and stereoselective manner. Epothilone analo gues 1a-d and 2a-d are more potent inhibitors of cancer cell proliferation than the corresponding parent epothilones B or D. (C) 2000 Elsevier Science Ltd. All rights reserved.