Abstract
The dried leaves of Eupatorium japonica THUNB. (Compositae) have been used as home remedies as diuretic, menogogic, and for jaundice. The fresh leaves have no odor but an aroma begins to evolve with passage of time. Based on this fact, it was assumed that an aromatic substance is present as a glycoside in the living plant. Coumarin, o-coumaric acid, and thymohydroquinone were isolated from the leaves and coumarin was considered to be responsible for the aroma.
