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Total synthesis of diazonamide A.

ABSTRACT: A total synthesis of the marine natural product diazonamide A (1) has been accomplished. This work features a highly stereoselective synthesis of the C(10) quaternary center and the central furanoindoline core enabled by an iminium-catalyzed alkylation-cyclization cascade. Additionally, a magnesium-mediated intramolecular macroaldolization and a palladium-catalyzed tandem borylation/annulation were developed to enable the closure of the two 12-membered macrocycles of diazonamide A. This synthesis involves 20 steps in its longest linear sequence and proceeds in 1.8% overall yield.

SUBMITTER: Knowles RR

PROVIDER: S-EPMC3408608 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Total synthesis of diazonamide A.

Knowles Robert R RR Carpenter Joseph J Blakey Simon B SB Kayano Akio A Mangion Ian K IK Sinz Christopher J CJ Macmillan David W C DW

Chemical science 20101224 2

A total synthesis of the marine natural product diazonamide A (1) has been accomplished. This work features a highly stereoselective synthesis of the C(10) quaternary center and the central furanoindoline core enabled by an iminium-catalyzed alkylation-cyclization cascade. Additionally, a magnesium-mediated intramolecular macroaldolization and a palladium-catalyzed tandem borylation/annulation were developed to enable the closure of the two 12-membered macrocycles of diazonamide A. This synthesi ...[more]

PMID: 22860227

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