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Novel Entry to the Tricyclic Core of Stemofoline and Didehydrostemofoline.

ABSTRACT: A novel approach to the tricyclic core of the Stemona alkaloids stemofoline and didehydrostemofoline has been discovered that features an intramolecular (3+2) dipolar cycloaddition of an unactivated carbon-carbon double bond with an azomethine ylide; the azomethine ylide was generated by an unprecedented reaction that occurred during a Swern oxidation of an ?-(N-cyanomethyl)-?-hydroxy ester. In separate experiments, the efficacy of introducing the requisite oxygen functionality at C(8) and the 1-butenyl side chain at C(3) was established.

SUBMITTER: Dietz J

PROVIDER: S-EPMC3079212 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Novel Entry to the Tricyclic Core of Stemofoline and Didehydrostemofoline.

Dietz Jochen J Martin Stephen F SF

Tetrahedron letters 20110401 17

A novel approach to the tricyclic core of the Stemona alkaloids stemofoline and didehydrostemofoline has been discovered that features an intramolecular (3+2) dipolar cycloaddition of an unactivated carbon-carbon double bond with an azomethine ylide; the azomethine ylide was generated by an unprecedented reaction that occurred during a Swern oxidation of an α-(N-cyanomethyl)-β-hydroxy ester. In separate experiments, the efficacy of introducing the requisite oxygen functionality at C(8) and the 1 ...[more]

PMID: 21516222

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