Thioglycoside synthesis

M. Jahn, H. Chen, J. Mullegger, J. Maries, R. A. Warren, and S. G. Withers, Thioglycosynthases Double mutant glycosidases that serve as scaffolds for thioglycoside synthesis, Chem. Commun. (Camb.) (2004) 274—275. 

The neighboring group participation mechanism requires two conditions a neighboring ester group and traas-configmation. For example, in the course of 3- and 4-thioglycoside synthesis, a solvent-dependent kinetically controlled stereoselective mechanism was found (Figure 8). 

J. F. Cassidy and J. M. Williams, Vinyl sulfones derived from thioglycosides synthesis and alkylation, Tetrahedron Lett., 27 (1986) 4355 1358. 

Jahn M, Maries J, Warren RA, Withers SG. Thioglycoligases mutant glycosidases for thioglycoside synthesis. Angew. Chem. Int. Ed. Engl. 2003 42 352-354. 

M. O. Contour, J. Defaye, M. Little, and E. Wong, Stereoselective thioglycoside synthesis. Part XI. Zirconium(IV) chloride-catalyzed synthesis of 1,2-trans-l-thioglycopyranoskles, Carbohydr. 

Fig. 8.63 Example of thioglycoside synthesis catalyzed by InCb-TiCU catalytic pair.

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. 

SCHEME 13. Synthesis of the trimanoside 59 by glycosidation of a thioglycoside or a trichloroacetimi-date with a diol acceptor in the presence of HC104—Si02. 

Y. W. Kim, A. L. Lovering, H. Chen, T. Kantner, L. P. McIntosh, N. C. Strynadka, and S. G. Withers, Expanding the thioglycoligase strategy to the synthesis of alpha-linked thioglycosides allows structural investigation of... 

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