Total Synthesis of the Unusual Monoterpenoid Indole Alkaloid (±)-Alstilobanine A


  • We are grateful to the National Institutes of Health (GM-087733) and the National Science Foundation (CHE-1105653) for financial support of this research.


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Tetracyclic monoterpene alkaloid alstilobanine A was obtained in racemic form. The pivotal steps of the total synthesis are a novel conjugate addition of an ester enolate with a nitrosoalkene, as well as a formal [2+2] intramolecular cycloaddition leading to a β-lactone to generate the requisite cis-fused 2-azadecalin moiety of the alkaloid. TMSE=trimethylsilylethoxy, Ts=4-toluenesulfonyl.