Studies on the Constituents of Viburnum Species. XVIII. Viburnols: Six New Triterpenoids from Viburnum dilatatum THUNB.

Six new triterpenoids, viburnols F, G, H, I, J and K, were isolated from the leaves of Viburnum dilatatum THUNB. (Caprifoliaceae). The structures were determined by extensive spectroscopic studies. Viburnols F, G and I are the first example of a new class of modified dammarane-type triterpenes.