Chem. Pharm. Bull., 55(6),950-952, June 2007

Notes

Two New Xanthones Isolated from the Stem Bark of Garcinia lancilimba

Nian-Yun YANG,^a Quan-Bin HAN,^a Xin-Wei CAO,^b Chun-Feng QIAO,^a Jing-Zheng SONG,^a Shi-Lin CHEN,^b Da-Jian YANG,^b Hillary YIU,^a and Hong-Xi XU^*,a

^a Chinese Medicine Laboratory, Hong Kong Jockey Club Institute of Chinese Medicine; Hong Kong, P. R. China: and ^b Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University; Hung Hom, Kowloon, Hong Kong, P. R. China. * To whom correspondence should be addressed. e-mail: xuhongxi@hkjcicm.org

Two new xanthones, 1,5,6-trihydroxy-6′,6′-dimethyl-2H-pyrano(2′,3′:3,4)-2-(3-methylbut-2-enyl)xanthone (1) and 1,6,7-trihydroxy-6′,6′-dimethyl-2H-pyrano(2′,3′:3,2)-4-(3-methylbut-2-enyl)xanthone (2), have been isolated from the stem bark of Garcinia lancilimba (Guttiferae), together with six known xanthones. Their structures were identified on the basis of extensive spectral evidence including detailed 2D NMR and HR-MS data. Two new compounds showed moderate inhibitory effect on human breast cancer MDA-MB-435S cell line.

Key words Garcinia lancilimba; Guttiferae; cytotoxicity; xanthone