Sequential one-pot glycosylations using 1-hydroxyl and 1-thiodonors.
Codée JD, van den Bos LJ, Litjens RE, Overkleeft HS, van Boom JH, et al.
Organic letters •
[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.