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Enantioselective total synthesis of (-)-citrinadin A and revision of its stereochemical structure.

ABSTRACT: The first enantioselective total synthesis of (-)-citrinadin A has been accomplished in 20 steps from commercially available materials via an approach that minimizes refunctionalization and protection/deprotection operations. The cornerstone of this synthesis features an asymmetric vinylogous Mannich addition of a dienolate to a chiral pyridinium salt to set the initial chiral center. A sequence of substrate-controlled reactions, including a highly stereoselective epoxidation/ring-opening sequence and an oxidative rearrangement of an indole to furnish a spirooxindole, are then used to establish the remaining stereocenters in the pentacyclic core of (-)-citrinadin A. The successful synthesis of citrinadin A led to a revision of the stereochemical structure of the core substructure of the citrinadins.

SUBMITTER: Bian Z

PROVIDER: S-EPMC3748604 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Enantioselective total synthesis of (-)-citrinadin A and revision of its stereochemical structure.

Bian Zhiguo Z Marvin Christopher C CC Martin Stephen F SF

Journal of the American Chemical Society 20130718 30

The first enantioselective total synthesis of (-)-citrinadin A has been accomplished in 20 steps from commercially available materials via an approach that minimizes refunctionalization and protection/deprotection operations. The cornerstone of this synthesis features an asymmetric vinylogous Mannich addition of a dienolate to a chiral pyridinium salt to set the initial chiral center. A sequence of substrate-controlled reactions, including a highly stereoselective epoxidation/ring-opening sequen ...[more]

PMID: 23837457

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