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Vinylogous addition of siloxyfurans to benzopyryliums: a concise approach to the tetrahydroxanthone natural products.

ABSTRACT: A concise approach to the tetrahydroxanthone natural products employing vinylogous addition of siloxyfurans to benzopyryliums and a late-stage Dieckmann cyclization has been developed. With this methodology, chiral, racemic forms of the natural products blennolides B and blennolide C have been synthesized in a maximum of four steps from a 5-hydroxychromone substrate. The regio- and diastereoselectivity of the vinylogous additions was probed using computational studies, which suggested the involvement of Diels-Alder-like transition states.

SUBMITTER: Qin T

PROVIDER: S-EPMC3099260 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Vinylogous addition of siloxyfurans to benzopyryliums: a concise approach to the tetrahydroxanthone natural products.

Qin Tian T Johnson Richard P RP Porco John A JA

Journal of the American Chemical Society 20110125 6

A concise approach to the tetrahydroxanthone natural products employing vinylogous addition of siloxyfurans to benzopyryliums and a late-stage Dieckmann cyclization has been developed. With this methodology, chiral, racemic forms of the natural products blennolides B and blennolide C have been synthesized in a maximum of four steps from a 5-hydroxychromone substrate. The regio- and diastereoselectivity of the vinylogous additions was probed using computational studies, which suggested the involv ...[more]

PMID: 21265529

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