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Synthesis of demissidine by a ring fragmentation 1,3-dipolar cycloaddition approach.

ABSTRACT: A synthesis of the steroidal alkaloid demissidine from epiandrosterone is reported. A ring fragmentation reaction that efficiently ruptured the D-ring of a diazo ester derivative of epiandrosterone to provide an aldehyde tethered ynoate product was key to this sequence. Incorporation of the indolizidine framework was achieved by an azomethine ylide 1,3-dipolar cycloaddition.

SUBMITTER: Zhang Z

PROVIDER: S-EPMC3671602 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Synthesis of demissidine by a ring fragmentation 1,3-dipolar cycloaddition approach.

Zhang Zhe Z Giampa Geoffrey M GM Draghici Cristian C Huang Qiufeng Q Brewer Matthias M

Organic letters 20130415 9

A synthesis of the steroidal alkaloid demissidine from epiandrosterone is reported. A ring fragmentation reaction that efficiently ruptured the D-ring of a diazo ester derivative of epiandrosterone to provide an aldehyde tethered ynoate product was key to this sequence. Incorporation of the indolizidine framework was achieved by an azomethine ylide 1,3-dipolar cycloaddition. ...[more]

PMID: 23586838

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