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The first transannular [4+3] cycloaddition reaction: synthesis of the ABCD ring structure of cortistatins.

ABSTRACT: A 14-membered macrocycle with an allene and a furan strategically located at across the ring from each other is synthesized using an allene ring closing metathesis reaction. Upon treatment of the macrocycle with a catalytic amount of Pd(OAc)(2) and other additives, the first transannular [4+3] cycloaddition occurred to yield 37% of a tetracyclic compound containing the ABC ring structure of the natural products cortistatins.

SUBMITTER: Craft DT

PROVIDER: S-EPMC2597840 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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The first transannular [4+3] cycloaddition reaction: synthesis of the ABCD ring structure of cortistatins.

Craft Derek T DT Gung Benjamin W BW

Tetrahedron letters 20081001 41

A 14-membered macrocycle with an allene and a furan strategically located at across the ring from each other is synthesized using an allene ring closing metathesis reaction. Upon treatment of the macrocycle with a catalytic amount of Pd(OAc)(2) and other additives, the first transannular [4+3] cycloaddition occurred to yield 37% of a tetracyclic compound containing the ABC ring structure of the natural products cortistatins. ...[more]

PMID: 19812680

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