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Reagent-Controlled Synthesis of the Branched Trisaccharide Fragment of the Antibiotic Saccharomicin B.

ABSTRACT: A concise synthesis of a branched trisaccharide, ?-l-Dig-(1 ? 3)-[?-l-Eva-(1 ? 4)]-?-d-Fuc, corresponding to saccharomicin B, has been developed via reagent-controlled ?-selective glycosylations. Starting from the d-fucose acceptor, l- epi-vancosamine was selectively installed using 2,3-bis(2,3,4-trimethoxyphenyl)cyclopropene-1-thione/oxalyl bromide mediated dehydrative glycosylation. Following deprotection, l-digitoxose was installed using the AgPF6/TTBP thioether-activation method to produce the trisaccharide as a single ?-anomer. This highly functionalized trisaccharide can potentially serve as both a donor and an acceptor for the total synthesis of the antibiotic saccharomicin B.

SUBMITTER: Soliman SE

PROVIDER: S-EPMC6094932 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Reagent-Controlled Synthesis of the Branched Trisaccharide Fragment of the Antibiotic Saccharomicin B.

Soliman Sameh E SE Bennett Clay S CS

Organic letters 20180523 11

A concise synthesis of a branched trisaccharide, α-l-Dig-(1 → 3)-[α-l-Eva-(1 → 4)]-β-d-Fuc, corresponding to saccharomicin B, has been developed via reagent-controlled α-selective glycosylations. Starting from the d-fucose acceptor, l- epi-vancosamine was selectively installed using 2,3-bis(2,3,4-trimethoxyphenyl)cyclopropene-1-thione/oxalyl bromide mediated dehydrative glycosylation. Following deprotection, l-digitoxose was installed using the AgPF<sub>6</sub>/TTBP thioether-activation method t ...[more]

PMID: 29790762

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