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Formal synthesis of (+)-brefeldin A: application of a zinc-mediated ring expansion reaction.

ABSTRACT: An efficient formal synthesis of (+)-brefeldin A was accomplished through a synthetic approach that relied upon three keys steps. The five-membered ring was generated in a stereocontrolled fashion through application of a tandem conjugate addition-intramolecular cyclization method developed by Toru. Ring-closing metathesis provided access to a twelve-membered beta-keto lactone, which was ring-expanded to the alpha,beta-unsaturated-gamma-keto lactone through a zinc carbenoid-mediated reaction. Conversion of this lactone to (+)-brefeldin A has been reported previously.

SUBMITTER: Lin W

PROVIDER: S-EPMC2572133 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature

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Formal synthesis of (+)-brefeldin A: application of a zinc-mediated ring expansion reaction.

Lin Weimin W Zercher Charles K CK

The Journal of organic chemistry 20070512 12

An efficient formal synthesis of (+)-brefeldin A was accomplished through a synthetic approach that relied upon three keys steps. The five-membered ring was generated in a stereocontrolled fashion through application of a tandem conjugate addition-intramolecular cyclization method developed by Toru. Ring-closing metathesis provided access to a twelve-membered beta-keto lactone, which was ring-expanded to the alpha,beta-unsaturated-gamma-keto lactone through a zinc carbenoid-mediated reaction. Co ...[more]

PMID: 17497923

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