Novel Cage Indoles from a Malaysian <i>Kopsia</i>

Abstract

The EtOH extract of the leaves of Kopsia teoi yielded the octacyclic alkaloids kopsinitarines A−D (1−4) and mersingines A and B (5 and 6), all possessing a novel cage carbon skeleton. The structures of the alkaloids were established by spectral methods and, in the case of kopsinitarine D (4), confirmed by X-ray analysis.