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Rapid access to the heterocyclic core of the calyciphylline A and daphnicyclidin A-type Daphniphyllum alkaloids via tandem cyclization of a neutral aminyl radical.

ABSTRACT: A streamlined approach to the tertiary amine-containing core of the calyciphylline A and daphnicyclidin A-type Daphniphyllum alkaloids is presented. A known carvone derivative is converted into the core structure in only four synthetic operations, and it is well poised for further elaboration. The key enabling methodology is a radical cyclization cascade beginning with addition of a secondary, neutral aminyl radical to the β-position of an enone, followed by trapping with a pendant alkyne.

SUBMITTER: Ibrahim AA

PROVIDER: S-EPMC3954529 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Rapid access to the heterocyclic core of the calyciphylline A and daphnicyclidin A-type Daphniphyllum alkaloids via tandem cyclization of a neutral aminyl radical.

Ibrahim Ahmad A AA Golonka Alexander N AN Lopez Alberto M AM Stockdill Jennifer L JL

Organic letters 20140207 4

A streamlined approach to the tertiary amine-containing core of the calyciphylline A and daphnicyclidin A-type Daphniphyllum alkaloids is presented. A known carvone derivative is converted into the core structure in only four synthetic operations, and it is well poised for further elaboration. The key enabling methodology is a radical cyclization cascade beginning with addition of a secondary, neutral aminyl radical to the β-position of an enone, followed by trapping with a pendant alkyne. ...[more]

PMID: 24506430

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