Abstract: Chemical investigation on the seeds of Calophyllum polyanthum Wall. et Choisy (Gutifferae) led to the isolation of two new dihydrocoumarins named calopolyanolide A (1) and B (2) together with known compounds, calanolide E2 (3), voleneol (4) and gallic acid (5). The structures of calopolyanolide A (1) and B (2) are elucidated as 6, 6 - dimethyl - 12a - (2a, 3a - H) - 12a - (2 - methyl - 3 -hydroxybutanoyl) - 8b - hydroxy - 4 - phenyl - pyranodihydrocoumarin (1) and 6, 6 - Dimethyl - 12a -(2a, 3(3 - H) - 12a - (2 - methyl - 3 - hydroxybutanoyl) - 8b - hydroxy - 4 - phenyl -pyranodihydrocoumarin (2) based on their spectroscopic analyses.

Key words: Calophllum polyanthum