Calophyllum spp have been known for their biological activities. This genus belongs to the Guttifereae family where are rich
with secondary metabolites such as xanthones, flavonoids and coumarins. Our recent phytochemical study on the bark of
Calophyllum sclerophyllum and Calophyllum hoseii has led to the isolation of six xanthones, one coumarin and one flavanoid.
These compounds are macluraxanthone (1), trapezifolixanthone (2), rubraxanthone (3), thwaitesixanthone (4),
dombakinaxanthone (5), osajaxanthone (6), calopolyanolide A (7) and catechin (8). We report here the structural elucidations
of these compounds based on the basis of detailed 1D-NMR (1H, 13C and DEPT) and 2D-NMR (COSY, HMQC and HMBC)