A process for synthesizing an oligosaccharide includes (a) activating a
protected glycosyl donor with a promoter in the absence of a glycosyl
acceptor to produce a reactive intermediate, the glycosyl donor having an
activatable aglycon at the anomeric carbon; (b) adding a protected
glycosyl donor/acceptor to the reactive intermediate to produce a new
glycosyl donor, the glycosyl donor/acceptor having both an activatable
aglycon at the anomeric carbon and a free hydroxyl group; (c) repeating
steps (a) and (b) to add any additional protected glycosyl
donor/acceptors; and (d) adding a protected glycosyl acceptor to produce
the oligosaccharide, the glycosyl acceptor having a free hydroxyl group
and a non-activatable aglycon at the anomeric carbon.
