Sesquiterpenes from Dictyopteris Divaricata. II. Dictyopterol and Dictyopterone

Abstract The structures of new sesquiterpenes, dictyopterol and dictyopterone, isolated from the essential oil of a brown algae, Dictyopteris divaricata Okamura (“Yezoyahazu”), have been shown to be selinen-1β-ol and selinen-1-one, respectively, on the basis of chemical and spectral data. Dictyopterol is an inseparable mixture of α- and β-isomers.