SYNTHESIS OF NOVEL 3'-TRIFLUOROMETHYL TAXOIDS THROUGH EFFECTIVE KINETIC RESOLUTION OF RACEMIC 4-CF3-BETA-LACTAMS WITH BACCATINS

The coupling of racemic 1-(t)Boc-4-CF3-beta-lactams with various C-10 modified baccatins has resulted in CF3-taxoids with diastereoselectivi ties ranging from 9:1 to one single isomer. The observed high diastere oselectivity is ascribed to the highly efficient enantiomer-differenti ation by the enantiopure lithium alkoxide of a baccatin III in the cou pling reaction with a racemic 1-(t)Boc-beta-lactam. These novel CF3-ta xoids have also been shown to exhibit significant increases in activit y against various cancer cell lines compared to either paclitaxel or d ocetaxel. In addition, the first asymmetric synthesis of a CF3-beta-la ctam via chiral ester enolate-imine cyclocondensation was performed wi th 50% enantioselectivity. (C) 1997 Wiley-Liss, Inc.