Goniolactones A-F, six new styrylpyrone derivatives from the roots of Goniothalamus cheliensis.

Six new styrylpyrone derivatives, goniolactones A-F (1-6), have been isolated from the roots of Goniothalamus cheliensis. The structures and stereochemistry of the new compounds were elucidated by interpretation of spectroscopic data and chemical methods. The relative configuration of goniolactone A (1) was determined by X-ray crystallography analysis, and the absolute configurations of goniolactones A (1) and B (2) were established by Mosher's method. Goniolactone B (2) exhibited significant cytotoxicity against A2780, HCT-8, and KB cells with IC(50) values of 7.40, 4.43, and 7.23 microM, respectively.