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    Preparation of S-glycoside surfactants and cysteine thioglycosides using minimally competent Lewis acid catalysis.

    Carbohydr Res 2016 Mar 6;422:1-4. Epub 2016 Jan 6.
    Department of Chemistry and Biochemistry, BIO5, The University of Arizona, 1306 E. University Blvd., Tucson, AZ 85721, USA. Electronic address:
    Here we report a method for the preparation of anomerically pure β-S-glycopyranosides (1,2-trans-glycosides) from the corresponding peracetate donors. S-glycosylation was performed in CHCl3 at reflux in the presence of a catalytic amount of InBr3. Deacylation of the intermediate peracetates were achieved under Zemplén conditions. Five pyranose examples, monosaccharides D-glucose and D-galactose and disaccharides cellobiose, maltose, and lactose, were used as donors, and five thiols including an α/ω dithiol and Fmoc-L-cysteine were used as acceptors. Melting points, high res MS, [α]D and NMR data ((1)H and (13)C, including COSY, HSQC and HMBC) are reported for compounds not previously described.
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