Syntheses and structure-activity relationships of novel 3′-difluoromethyl and 3′-trifluoromethyl-taxoids

Novel 3′-difluoromethyl-taxoids and 3′-trifluoromethyl-taxoids were synthesized and evaluated for their in vitro cytotoxicities against human breast, non-small cell lung, and colon cancer cell lines. These second-generation fluoro-taxoids exhibit two orders of magnitude higher potency than paclitaxel against multidrug-resistant cancer cell lines. Structure-activity relationship of these highly potent fluoro-taxoids is discussed.