Amentoflavon (biflavonoid) had been isolated from the leaves of Calophyllum pulcherimmum Wall. The ethyl acetate extracts of this leaves gave yellow powder with melting point 267-268°C. The structure was identified by spectroscopic methods including 1D and 2D NMR experiments as well as mass spectrometry. The structure does not indicate active antibacterial activity against Escherichia coli, St…