Glycoside synthesis thioglycosides

The lactonized phenyl 2-thioglycosides of dimeric (26) [41] and trimeric (27) [42] sialic acids, which were prepared from the corresponding oligosialic acids according to the procedure employed for the monosialyl derivatives, were each coupled with the suitably protected sugar acceptors (14, 16, 17, and 19) by use of NIS-TfOH as a promoter in acetonitrile, as just described for the monosialyl glycoside synthesis (Fig. 3). 

Fugedi, P, Garegg, P J, A novel promoter for the efficient constmction of, 2-trans hnkages in glycoside synthesis, using thioglycosides as glycosyl donors, Carbohydr. Res., 149, C9-C12, 1986. 

Ldnn, H, Sulfurylchloride trifluoromethanesulfonic acid — a novel promoter system for glycoside synthesis using thioglycosides as glycosyl donors, Glycoconjugate J., 4, 117-118, 1987. 

Kallin, E, Lonn, H, Norberg, T, Glycosidations with thioglycosides activated by suUuryl chloride trifluoromethanesulfonic acid — synthesis of a human-blood group-B trisaccharide glycoside, Glycoconjugate J., 5, 3-8, 1988. 

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