Studies on the constituents of medicinal and related plants in Sri Lanka. II. Isolation and structures of new .GAMMA.-pyrone and related compounds from Hypericum mysorense Heyne.

Neutral constituents of Hypericum mysorense HEYNE, collected in Sri Lanka, were examined. Hyperenone-A, mysorenone-A, and compound-C (methyl phenacyl 1, 1-dimethylprop-2-enyl-malonate) were isolated and their structures were determined on the basis of chemical and spectroscopic evidence. Four known xanthones were also isolated and identified.