1-Thioglycosides as glycosyl donors

The synthesis is an excellent example of the use of thioglycosides as glycosyl donors in the block synthesis of complex oligosaccharides as well as the use of partial glycosylation of diols to achieve short paths to the target. 

Figure2.7 Two-stage activation procedure using glycosyl fluoride and thioglycoside as glycosyl donor.

Scheme 5.3 Stepwise assembly of the solid-phase-bound heptasaccharide thioglycosides as glycosyl donors and DMTST as activator.29...

Scheme 7 Methods for glycosyl fluorides using (a) thioglycosides [23] and (b) lactols [29,30], Thioglycosides as Glycosyl Donors...

Garegg PJ. Thioglycosides as glycosyl donors in oligosaccharide synthesis. Adv. Carbohydr. Chem. Biochem. 1997 52 179-205. 

The capacity of these thioglycosides as glycosyl donors was evaluated using various thiophilic promoters and three different acceptors, one primary (66) and two secondary (67 and 68), the latter relevant for the synthesis of H. influenzae type e structures. The yields obtained were extraordinary, both with the benzoylated and the benzylated donor (1.5 equiv.) and with all three acceptors quantitative or nearly quantitative yields of disaccharide products were observ-... 

Andersson, F, Fugedi, P, Garegg, P J, Nashed, M, Synthesis of 1,2-cA-linked glycosides using dimethyl(methylthio)sulfonium triflate as promoter and thioglycosides as glycosyl donors. Tetrahedron Lett., 27, 3919-3922, 1986. 

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. 

---