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Total syntheses of isodomoic acids G and H.

ABSTRACT: The total syntheses of marine natural products belonging to the kainoid family, isodomoic acids G and H, are described. The strategic connection involves a sequential silylcarbocyclization/silicon-based cross-coupling process. These total syntheses were achieved efficiently via a 12- and a 13-step, longest-linear sequence, respectively. The key transformations include a diastereoselective rhodium-catalyzed carbonylative silylcarbocyclization reaction of an (l)-vinylglycine-derived 1,6-enyne, a desilylative iodination reaction, as well as an alkenyl-alkenyl silicon-based cross-coupling reaction. The mechanistic insight garnered during the investigation of the iododesilylation reaction enabled stereocontrolled introduction of the iodine with either inversion or retention of double bond configuration. The invertive desilylative iodination leads to the total synthesis of isodomoic acid H, while its congener, isodomoic acid G, was obtained via a retentive iododesilylation.

SUBMITTER: Denmark SE

PROVIDER: S-EPMC2760019 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Total syntheses of isodomoic acids G and H.

Denmark Scott E SE Liu Jack Hung-Chang JH Muhuhi Joseck M JM

Journal of the American Chemical Society 20091001 40

The total syntheses of marine natural products belonging to the kainoid family, isodomoic acids G and H, are described. The strategic connection involves a sequential silylcarbocyclization/silicon-based cross-coupling process. These total syntheses were achieved efficiently via a 12- and a 13-step, longest-linear sequence, respectively. The key transformations include a diastereoselective rhodium-catalyzed carbonylative silylcarbocyclization reaction of an (l)-vinylglycine-derived 1,6-enyne, a d ...[more]

PMID: 19807173

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