Chitooligosaccharide Synthesis Using an Ionic Tag
An environmentally improved synthesis of the N-differentiated chitotetrasaccharide CO-IV-(NH2), a key intermediate for the preparation of lipochitooligosaccharides and the TMG-chitotriomycin, is reported based on a chromatography-free ionic-liquid tagging approach. The method involves the glycosylation of ionic-liquid-tagged acceptors with thioglucosamine donors leading to the stereoselective formation of β-(14)-linked glucosamine-containing oligomers.