Three new carboxylic acids, rhinacanthinic acids A-C (1-3), together with six known naphthoquinones and one known d-
lactone were isolated from the stems of Rhinacanthus nasutus. The structures of the isolated compds. were elucidated
based on spectroscopic evidence. Their antiviral activity against herpes simplex virus type-2 (HSV-2) and cytotoxicity
were examd.