Sequential one-pot glycosylations using 1-hydroxyl and 1-thiodonors
Jeroen D C Codée1, Leendert J van den Bos, Remy E J N Litjens
1Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Abstract:
[reaction: see text] A novel sequential glycosylation procedure is described that combines the use of 1-hydroxyl and thiodonors. The Ph(2)SO/Tf(2)O-mediated dehydrative condensation of 1-hydroxyl donors with thioglycosides affords in good yield the thiodisaccharides, which in turn can be activated by the same activator system to furnish trisaccharides. The alpha-Gal epitope and a hyaluronan trisaccharide were efficiently assembled in a one-pot procedure.
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