Two New Eremophilane-Type Sesquiterpenoids from Japanese Liverwort Bazzania japonica.

Two new eremophilane-type sesquiterpenoids, fusumaols A (1) and B (2), were isolated from the stem-leafy liverwort, Bazzania japonica collected in Mori-Machi, Shizuoka, Japan. Their structures were established using extensive spectroscopic (IR, MS, and 2D NMR) data, and the absolute configuration of 1 was determined by the modified Mosher's method. This is the first time eremophilanes have been discovered in the liverwort genus Bazzania. Compounds 1 and 2 were evaluated for their repellent activity against the adult population of the rice weevil Sitophilus zeamais using the modified filter paper impregnation method. Both sesquiterpenoids showed moderate repellent activities.