Antiproliferative compounds of Artabotrys madagascariensis from the Madagascar rainforest

Abstract

Bioassay-guided fractionation of an ethanol extract of Artabotrys madagascariensis led to the isolation of the new compound artabotrene (1), two butenolides (2 and 3), and the tetracyclic triterpene polycarpol (4). Structure elucidation was determined on the basis of one and two-dimensional NMR, and absolute configuration of compounds 2–4 was verified by analysis of CD and optical rotation spectra. Two of the isolates, melodorinol (2) and acetylmelodorinol (3), were found to display antiproliferative activity against five different tumour cell lines with IC₅₀ values ranging from 2.4 to 12 µM.

Keywords:

• Butenolides
• Artabotrys
• Annonaceae
• Antiproliferative activity
• NMR
• HPLC

Acknowledgments

This work was supported by International Cooperative Biodiversity Grant Number TW 00313 from the Fogarty Center, National Institutes of Health, and this support is gratefully acknowledged. We also thank Mr. Bill Bebout and Ms. Anne Campbell for obtaining MS data, Mr. Kim Harich for obtaining CD data, and Mr. Tom Glass for assistance obtaining NMR spectra. Field work essential for this project was conducted under a collaborative agreement between the Missouri Botanical Garden and the Parc Botanique et Zoologique de Tsimbazaza and a multilateral agreement between the ICBG partners, including the Centre National d’Applications et des Recherches Pharmaceutiques. We gratefully acknowledge courtesies extended by the Government of Madagascar (Ministère des Eaux et Forêts).