title: A Direct Method for β-Selective Glycosylation with an N-Acetylglucosamine Donor Armed by a 4-O-TBDMS Protecting Group.
abstract: A new direct method for β-selective glycosylation with anN-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 β-selectivity, while sterically hindered acceptors were less efficient.
authors.affiliation: Oceanography Section, Science Research Center, Kochi University, Otsu, Nankoku-shi, Kochi 783-8502, Japan. htanaka@kochi-u.ac.jp.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Tanaka
authors.affiliation: Laboratory of Natural Products Chemistry, Faculty of Science, Kochi University, Akebono-cho, Kochi-shi, Kochi 780-8520, Japan. a_paradise_country@yahoo.co.jp.
authors.forename: Yu
authors.initials: Y
authors.lastname: Hamaya
authors.affiliation: Laboratory of Natural Products Chemistry, Faculty of Science, Kochi University, Akebono-cho, Kochi-shi, Kochi 780-8520, Japan. kotsuki@kochi-u.ac.jp.
authors.forename: Hiyoshizo
authors.initials: H
authors.lastname: Kotsuki
mesh_terms: D000117:Acetylglucosamine / Q000737:chemistry*; D006031:Glycosylation; D055601:Organic Chemistry Phenomena
chemical_list: D000117:Acetylglucosamine
keywords: N-acetylglucosamine; O-TBDMS protecting group; remote protecting group effect; β-selective glycosylation