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Synthesis of the Non-Reducing Hexasaccharide Fragment of Saccharomicin B.

ABSTRACT: A synthesis of the nonreducing end hexasaccharide of saccharomicin B, ?-l-Eva-(1?4)-?-l-Eva-(1?4)-?-l-Dig-(1?4)-?-l-Eva-(1?4)-?-l-Dig-(1?4)-?-d-Fuc, has been developed. Selective glycosylations of l-digitoxose (l-Dig) using AgPF6/TTBP-mediated thioether activation and l-4-e pi-vancosamine (l-Eva) using Tf2O/DTBMP-mediated sulfoxide activation produced the hexasaccharide as a single diastereomer in very good yield. This hexasaccharide is properly functionalized to serve as a glycosyl donor for the total synthesis of saccharomicin B.

SUBMITTER: Jana M

PROVIDER: S-EPMC6465119 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Synthesis of the Non-Reducing Hexasaccharide Fragment of Saccharomicin B.

Jana Manas M Bennett Clay S CS

Organic letters 20181114 23

A synthesis of the nonreducing end hexasaccharide of saccharomicin B, α-l-Eva-(1→4)-α-l-Eva-(1→4)-α-l-Dig-(1→4)-α-l-Eva-(1→4)-α-l-Dig-(1→4)-β-d-Fuc, has been developed. Selective glycosylations of l-digitoxose (l-Dig) using AgPF6/TTBP-mediated thioether activation and l-4-e pi-vancosamine (l-Eva) using Tf2O/DTBMP-mediated sulfoxide activation produced the hexasaccharide as a single diastereomer in very good yield. This hexasaccharide is properly functionalized to serve as a ...[more]

PMID: 30427691

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