A New, Iterative Strategy of Oligosaccharide Synthesis Based on Highly Reactive β-Bromoglycosides Derived from Selenoglycosides

Stereoselective conversion of a selenoglycoside to a β-bromoglycoside in the absence of a glycosyl acceptor followed by the coupling with another selenoglycoside affords the corresponding glycosylated selenoglycoside, which could be directly used for the next glycosylation. The iteration of this sequence allows the synthesis of a variety of oligosaccharides including an elicitor active heptasaccharide.