Isolation, identification, semi-synthesis of aziditaxel derivatives and their biological evaluation

Two new taxoids (5 and 6) were obtained by isolating impurities in aziditaxel, and their structures were characterized based on data analysis of 1H NMR, 13C NMR, HPLC-MS, and through comparison with literature. In order to test their cytotoxicities against human nonsmall lung cancer cell lines (A549), sufficient amounts of compounds 5 and 6 were obtained by semi-synthesis and both of them showed equipotent cytotoxiesty compared with taxol, docetaxel, and aziditaxel.