Convenient access to 4-O-glycosylated 1,5-anhydro-D-fructoses via disaccharide-derived 2-hydroxyglycal esters

Efficient six-step protocols are described for the conversion of common disaccharides, such as maltose, cellobiose, or lactose, into the corresponding 4-O-glycosyl-1,5-anhydro-D-fructoses. Overall yields of 40-45% are favorably compared to the alternative eleven-step procedure from their monosaccharide components (similar to 15%). (C) 2011 Elsevier Ltd. All rights reserved.