Cytotoxic styrylpyrones from Goniothalamus amuyon.

Two new styrylpyrones, (6R,7R,8R)-8-methoxygoniodiol (1) and (6R,7R,8R)-8-chlorogoniodiol (2), together with seven known styrylpyrones and eight other known compounds, were isolated from the leaves and/or stems of Goniothalamus amuyon. The structures of 1 and 2 were elucidated by spectral data interpretation, and the absolute stereochemistry of styrylpyrones in the diol and triol series was confirmed by X-ray crystallographic analysis and CD spectral data. Compound 2 demonstrated significant selective cytotoxicity toward the HONE-1 cancer cell line.