A new prenylated xanthone from the branches of Calophyllum inophyllum.

The investigation of chemical constituents from the branches of Calophyllum inophyllum Linn led to the isolation of a new prenylated xanthone, named caloxanthone Q (1), together with three known compounds, 2-deprenylrheediaxanthone B (2), jacareubin (3), and 6-deoxyjacareubin (4). Their structures were completely elucidated on the basis of spectroscopic methods (UV, IR, HR-ESI-MS, 1D NMR, and 2D NMR).