A SIMPLE SYNTHESIS OF C-GLUCOSIDES RELATED TO THE ANTITUMOR AGENT ETOPOSIDE

The synthesis of four new lignan derivatives 2a, 2b, 3a and 3b related to the anticancer agent etoposide has been accomplished. In these compounds a methylene or ethylene group of a C-glucoside separates the glucosidic moiety as present in etoposide (1) from its lignan aglycone bonded by an ethereal function. The key step in the synthesis involves the reaction of a benzylated alditol 4 or 5 and the unprotected 4'-demethylepipodophyllotoxin (6).