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A practical, enantioselective synthetic route to a key precursor to the tetracycline antibiotics.

ABSTRACT: A practical, enantioselective synthetic route to a key precursor to the tetracycline antibiotics is reported. The route proceeds in nine steps (21% yield) from the commercial substance methyl 3-hydroxy-5-isoxazolecarboxylate. Key steps in the route involve enantioselective addition of divinylzinc to 3-benzyloxy-5-isoxazolecarboxaldehyde and an endo-selective intramolecular furan Diels-Alder cycloaddition reaction. The route described has provided more than 40 g of chromatographically pure 1 with 93% ee.

SUBMITTER: Brubaker JD

PROVIDER: S-EPMC3178443 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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A practical, enantioselective synthetic route to a key precursor to the tetracycline antibiotics.

Brubaker Jason D JD Myers Andrew G AG

Organic letters 20070811 18

A practical, enantioselective synthetic route to a key precursor to the tetracycline antibiotics is reported. The route proceeds in nine steps (21% yield) from the commercial substance methyl 3-hydroxy-5-isoxazolecarboxylate. Key steps in the route involve enantioselective addition of divinylzinc to 3-benzyloxy-5-isoxazolecarboxaldehyde and an endo-selective intramolecular furan Diels-Alder cycloaddition reaction. The route described has provided more than 40 g of chromatographically pure 1 with ...[more]

PMID: 17691796

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