Efficient synthesis of α,β-unsaturated γ-lactones linked to sugars

A series of structurally diverse unsaturated supar-derived lactones has been prepared. alpha,beta -Butenolides were introduced to the sugar moiety starting from epoxides. while alpha -methylene-gamma -lactones were constructed from a carbonyl precursor, either an aldehyde. a ketone or a lactone. In the Inst case. an unprecedented Reformatsky-type: reaction has been developed. (C) 2001 Published by Elsesvier Science Ltd.