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Enantioselective synthesis of the ABC ring motif of norzoanthamine based on asymmetric Robinson annulation reactions.

ABSTRACT: An enantioselective strategy for the synthesis of tetracyclic motif 5, representing the northern fragment of norzoanthamine, is presented. Key to the strategy is the use of two asymmetric Robinson annulation reactions that produce the tricyclic ABC ring system with excellent stereoselectivity. Further functionalization at the periphery of the C ring produces compound 5 containing six contiguous stereocenters of the natural product.

SUBMITTER: Nguyen TX

PROVIDER: S-EPMC3153989 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Enantioselective synthesis of the ABC ring motif of norzoanthamine based on asymmetric Robinson annulation reactions.

Nguyen Thong X TX Dakanali Marianna M Trzoss Lynnie L Theodorakis Emmanuel A EA

Organic letters 20110526 13

An enantioselective strategy for the synthesis of tetracyclic motif 5, representing the northern fragment of norzoanthamine, is presented. Key to the strategy is the use of two asymmetric Robinson annulation reactions that produce the tricyclic ABC ring system with excellent stereoselectivity. Further functionalization at the periphery of the C ring produces compound 5 containing six contiguous stereocenters of the natural product. ...[more]

PMID: 21615125

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