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Expanding the scope of stereoselective α-galactosylation using glycosyl chlorides.

ABSTRACT: Recently, we reported that silver(I) oxide mediated Koenigs-Knorr glycosylation reaction can be dramatically accelerated in the presence of catalytic acid additives. We have also investigated how well this reaction works in application to differentially protected galactosyl bromides. Reported herein is the stereoselective synthesis of α-galactosides with galactosyl chlorides as glycosyl donors. Chlorides are easily accessible, stable, and can be efficiently activated for glycosylation. In this application, the most favorable reactions conditions comprised cooperative Ag₂SO₄ and Bi(OTf)₃ promoter system.

SUBMITTER: Shadrick M

PROVIDER: S-EPMC9677435 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Expanding the scope of stereoselective α-galactosylation using glycosyl chlorides.

Shadrick Melanie M Stine Keith J KJ Demchenko Alexei V AV

Bioorganic & medicinal chemistry 20220926

Recently, we reported that silver(I) oxide mediated Koenigs-Knorr glycosylation reaction can be dramatically accelerated in the presence of catalytic acid additives. We have also investigated how well this reaction works in application to differentially protected galactosyl bromides. Reported herein is the stereoselective synthesis of α-galactosides with galactosyl chlorides as glycosyl donors. Chlorides are easily accessible, stable, and can be efficiently activated for glycosylation. In this a ...[more]

PMID: 36202065

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