Arboridinine, a Pentacyclic Indole Alkaloid with a New Cage Carbon–Nitrogen Skeleton Derived from a Pericine Precursor

Abstract

A new monoterpene indole alkaloid characterized by an unprecedented pentacyclic cage skeleton, arboridinine (<b>1</b>), was isolated from a Malaysian <i>Kopsia</i> species. The structure and absolute configuration of the alkaloid were determined based on NMR, MS, and X-ray diffraction analysis. A possible biogenetic pathway from a pericine precursor is presented