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α-Selective Glycosylation with β-Glycosyl Sulfonium Ions Prepared via Intramolecular Alkylation.

ABSTRACT: Stereoselective glycosylation remains the main challenge in the chemical synthesis of oligosaccharides. Herein we report a simple method to convert thioglycosides into β-sulfonium ions via an intramolecular alkylation reaction, leading to highly α-selective glycosylations for a variety of glycosyl acceptors. The influence of the thioglycoside substituent and the protecting group pattern on the glycosyl donor was investigated and showed a clear correlation with the observed stereoselectivity.

SUBMITTER: Moons SJ

PROVIDER: S-EPMC6454400 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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α-Selective Glycosylation with β-Glycosyl Sulfonium Ions Prepared via Intramolecular Alkylation.

Moons Sam J SJ Mensink Rens A RA Bruekers Jeroen P J JPJ Vercammen Maurits L A MLA Jansen Laura M LM Boltje Thomas J TJ

The Journal of organic chemistry 20190307 7

Stereoselective glycosylation remains the main challenge in the chemical synthesis of oligosaccharides. Herein we report a simple method to convert thioglycosides into β-sulfonium ions via an intramolecular alkylation reaction, leading to highly α-selective glycosylations for a variety of glycosyl acceptors. The influence of the thioglycoside substituent and the protecting group pattern on the glycosyl donor was investigated and showed a clear correlation with the observed stereoselectivity. ...[more]

PMID: 30808170

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