Trifluoroacetamido Substituted Sialyl Donors for the Preparation of Sialyl Galactosides

Abstract

Glycosidations of sialyl donor (1a), bearing a trifluoroacetamido group at C5, with partially protected D-galactosyl derivatives afforded (2,3)-linked disaccharides in high yields and excellent stereoselectivities, even when sterically hindered alcohols were used as glycosyl acceptors. Good yields but modest stereoselectivities were obtained when (1a) was glycosidated with the C6 hydroxyl of D-galactosides.