Calophyline A, a New Rearranged Monoterpenoid Indole Alkaloid from <i>Winchia calophylla</i>

Abstract

Calophyline A (<b>1</b>), a novel unprecedented rearranged monoterpenoid indole alkaloid, along with a new natural product <i>N</i>-methyl aspidodasycarpine (<b>2</b>) and six known analogues, was isolated from the trunk barks of <i>Winchia calophylla</i>. The structure of compound <b>1</b> was elucidated on the basis of spectroscopic data and then confirmed by a single-crystal X-ray crystallographic analysis. A hypothetical biogenetic pathway for compound <b>1</b> was proposed. All isolated compounds were evaluated for their in vitro cytotoxicity against a small panel of human cancer cell lines