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A Direct Method for ?-Selective Glycosylation with an N-Acetylglucosamine Donor Armed by a 4-O-TBDMS Protecting Group.

ABSTRACT: A new direct method for ?-selective glycosylation with an N-acetylglucosamine (GlcNAc) donor was developed. This substrate, which can be readily prepared from commercially available GlcNAc in two steps, contains a 4-O-tert-butyldimethylsilyl (TBDMS) protecting group as a key component. We found that this functionality could have a favorable effect on the reactivity of the GlcNAc donor. Glycosylation with the armed donor using primary alcohols in the presence of a catalytic amount of trimethylsilyl trifluoromethanesulfonate (TMSOTf) in 1,2-dichloroethane smoothly gave the desired coupling products in good yields with complete ?-selectivity, while sterically hindered acceptors were less efficient.

SUBMITTER: Tanaka H

PROVIDER: S-EPMC6155425 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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A Direct Method for β-Selective Glycosylation with an N-Acetylglucosamine Donor Armed by a 4-O-TBDMS Protecting Group.

Tanaka Hidenori H Hamaya Yu Y Kotsuki Hiyoshizo H

Molecules (Basel, Switzerland) 20170308 3

A new direct method for β-selective glycosylation with an N-acetylglucosamine (GlcNAc) donor was developed. This substrate, which can be readily prepared from commercially available GlcNAc in two steps, contains a 4-O-tert-butyldimethylsilyl (TBDMS) protecting group as a key component. We found that this functionality could have a favorable effect on the reactivity of the GlcNAc donor. Glycosylation with the armed donor using primary alcohols in the presence of a catalytic a ...[more]

PMID: 28282905

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