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Enantioselective total syntheses of nankakurines A and B: confirmation of structure and establishment of absolute configuration.

ABSTRACT: Total syntheses of (+)-nankakurine A (2) and (+)-nankakurine B (3) were accomplished by a sequence that employs an intramolecular dipolar cycloaddition of an azomethine imine intermediate to form the azatricyclic moiety and establish the relative configuration of the spiropiperidine ring. These syntheses, together with the synthesis of the originally purported structure 1 of nankakurine A, rigorously establish the relative and absolute configuration of these structurally unusual Lycopodium alkaloids. The syntheses are sufficiently concise that gram quantities of (+)-nankakurine A (2) and (+)-nankakurine B (3) will be available for further biological studies.

SUBMITTER: Nilsson BL

PROVIDER: S-EPMC3074941 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Enantioselective total syntheses of nankakurines A and B: confirmation of structure and establishment of absolute configuration.

Nilsson Bradley L BL Overman Larry E LE Read de Alaniz Javier J Rohde Jason M JM

Journal of the American Chemical Society 20080802 34

Total syntheses of (+)-nankakurine A (2) and (+)-nankakurine B (3) were accomplished by a sequence that employs an intramolecular dipolar cycloaddition of an azomethine imine intermediate to form the azatricyclic moiety and establish the relative configuration of the spiropiperidine ring. These syntheses, together with the synthesis of the originally purported structure 1 of nankakurine A, rigorously establish the relative and absolute configuration of these structurally unusual Lycopodium alkal ...[more]

PMID: 18680252

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