Enzymatically Activated Glyco-Prodrugs of Doxorubicin Synthesized by a Catalysis-Free Diels-Alder Reaction.

The severe side effects associated with the use of anthracycline anticancer agents continues to limit their use. Herein we describe the synthesis and preliminary biological evaluation of three enzymatically activatable doxorubicin-oligosaccharide prodrugs. The synthetic protocol allows late stage variation of the carbohydrate and is compatible with the use of disaccharides such as lactose as well as more complex oligosaccharides such as xyloglucan oligomers. The enzymatic release of doxorubicin from the prodrugs by both protease (plasmin) and human carboxylesterases (hCE1 and 2) was demonstrated in vitro and the cytotoxic effect of the prodrugs was assayed on MCF-7 breast cancer cells.