Xanthones from Garcinia cowa flowers and their cytotoxicity

Abstract

Keywords: Garcinia cowa, Clusiaceae, xanthones, cytotoxicity

Five xanthones including 6-O-methylmangostanin (1), mangostanin (2), garcinianone A (3), mangostanol (4) and a-mangostin (5) were isolated from the flowers of Garcinia cowa Roxb. (Cha-muang, family Clusiaceae). This is the first report of mangostanol (4) as a constituent of G. cowa. Their identification was performed using one- and two-dimensional ¹H and ¹³C NMR techniques and comparison with literatures. Cytotoxicity of these compounds against SW620, BT474, HepG2, KATO-III and CHAGO-K1 cell lines was evaluated. a-Mangostin was strongly cytotoxic against all cell lines tested, whereas mangostanin exhibited cytotoxicity specifically against CHAGO-K1 cells.