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

ABSTRACT: 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.

SUBMITTER: Szabo LZ

PROVIDER: S-EPMC8876251 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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

Szabó Lajos Z LZ Hanrahan Dillon J DJ Jones Evan M EM Martin Erin E Pemberton Jeanne E JE Polt Robin R

Carbohydrate research 20160106

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 ...[more]

PMID: 26795078

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