Guttiferones Q-S, cytotoxic polyisoprenylated benzophenones from the pericarp of Garcinia cochinchinensis

Three new polyisoprenylated benzophenones, guttiferones Q-S, the known guttiferone I and four xanthones, dulxanthone A, 1,3,5-trihydroxy-6-methoxy-7-(3-methylbut-2-enyl)xanthone, 1,3,5-trihydroxy-13,13-dimethyl-2H-pyran[7,6-b] xanthen-9-one and 1,3-dihydroxy-5,6-dimethoxy-7-(3-methylbut-2-enyl) xanthone, as well as trimethyl citrate, were isolated from the pericarp of Garcinia cochinchinensis collected in Vietnam. Their structures were elucidated using spectroscopic methods (mainly 1-D and 2-D NMR). All the guttiferones were tested for their cytotoxicity towards three human cancer cell lines, MCF-7, Hela, and NCI-H460. Among the tested compounds, guttiferone Q showed potent cytotoxicity, having IC50 values in the range of 2.74-4.04 mu g/ml, against the investigated cells. (C) 2011 Phytochemical Society of Europe. Published by Elsevier B. V. All rights reserved.