New bioactive taxoids from cell cultures of Taxus baccata

Four new taxoids were isolated from cell cultures of Taxus baccata. Their structures were elucidated by spectroscopic analyses. Two were the aglycones corresponding to previously isolated 7-O-xylosides of taxol C [1] and 10-deacetyltaxol C [2]. The third [3] had an N-methylated side-chain, while the fourth, named taxcultine [4], contained an n-propyl group on the side-chain. All four compounds actively promoted tubulin assembly. Taxol C [1] showed potent and selective cytotoxicity in the NCI human cell line screen.