(−)-Goniomitine is an indole alkaloid of an unusual structural type, isolated from Gonioma malagasy Markgr & Boiteau (Apocynaceae) in 1987 by Husson et al. who proposed a biogenetic filiation between goniomitine and Aspidosperma alkaloids, regarded as its precursors. Our article describes the first biomimetic semisynthesis of both enantiomers of goniomitine, accomplished in nine steps starting from (−)- and (+)-vincadifformine, an alkaloid with an Aspidosperma skeleton. As (−)-vincadifformine is readily available from (−)-tabersonine, the major alkaloid from seeds of Voacanga africana Stapf., our process thus constitutes an original access to unnatural (+)-goniomitine, which was only accessible by total synthesis so far.

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