Chemo-enzymatic synthesis of ester-linked taxol–oligosaccharide conjugates as potential prodrugs

7-Glycolylpaclitaxel 2″-O-α-glucooligosaccharides, novel taxol (paclitaxel) prodrugs of ester-linked oligosaccharide series compounds, were synthesized by chemo-enzymatic procedures, including enzymatic transglycosylations with α-glucosidase and cyclodextrin glucanotransferase. The water-solubility of 7-glycolylpaclitaxel 2″-O-α-glucopentaoside was 2.7 mM, which was 6.8 thousand-fold higher than that of paclitaxel. C-7 modification of paclitaxel with a longer oligosaccharide chain decreased the in vitro cytotoxicity of paclitaxel against KF human ovarian cancer cells.