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Enantioselective Synthesis of (-)-Vallesine: Late-Stage C17-Oxidation via Complex Indole Boronation.

ABSTRACT: The first enantioselective total synthesis of (-)-vallesine via a strategy that features a late-stage regioselective C17-oxidation followed by a highly stereoselective transannular cyclization is reported. The versatility of this approach is highlighted by the divergent synthesis of the archetypal alkaloid of this family, (+)-aspidospermidine, and an A-ring-oxygenated derivative, (+)-deacetylaspidospermine, the precursor to (-)-vallesine, from a common intermediate.

SUBMITTER: Antropow AH

PROVIDER: S-EPMC6021010 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Enantioselective Synthesis of (-)-Vallesine: Late-Stage C17-Oxidation via Complex Indole Boronation.

Antropow Alyssa H AH Garcia Nicholas R NR White Kolby L KL Movassaghi Mohammad M

Organic letters 20180604 12

The first enantioselective total synthesis of (-)-vallesine via a strategy that features a late-stage regioselective C17-oxidation followed by a highly stereoselective transannular cyclization is reported. The versatility of this approach is highlighted by the divergent synthesis of the archetypal alkaloid of this family, (+)-aspidospermidine, and an A-ring-oxygenated derivative, (+)-deacetylaspidospermine, the precursor to (-)-vallesine, from a common intermediate. ...[more]

PMID: 29863356

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