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Highly Selective β-Mannosylations and β-Rhamnosylations Catalyzed by Bis-thiourea.

ABSTRACT: We report highly β-selective bis-thioureas-catalyzed 1,2-cis-O-pyranosylations employing easily accessible acetonide-protected donors. A wide variety of alcohol nucleophiles, including complex natural products, glycosides, and amino acids were β-mannosylated and β-rhamnosylated successfully using an operationally simple protocol under mild and neutral conditions. Less nucleophilic acceptors such as phenols were also glycosylated efficiently in excellent yields and with high β-selectivities.

SUBMITTER: Li Q

PROVIDER: S-EPMC7523191 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Highly Selective β-Mannosylations and β-Rhamnosylations Catalyzed by Bis-thiourea.

Li Qiuhan Q Levi Samuel M SM Jacobsen Eric N EN

Journal of the American Chemical Society 20200626 27

We report highly β-selective bis-thioureas-catalyzed 1,2-<i>cis-O-</i>pyranosylations employing easily accessible acetonide-protected donors. A wide variety of alcohol nucleophiles, including complex natural products, glycosides, and amino acids were β-mannosylated and β-rhamnosylated successfully using an operationally simple protocol under mild and neutral conditions. Less nucleophilic acceptors such as phenols were also glycosylated efficiently in excellent yields and with high β-selectivitie ...[more]

PMID: 32527078

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