Dysoanthraquinone and 2-demethyldysoanthraquinone from Dysosma majoense

Two new anthraquinones, dysoanthraquinone and 2-demethyldysoanthraquinone, were separated from Dysosma majoense. Both compounds contain methylendioxy at 6—C, 7—C. It is very interesting in terms of biogenetic pathway that they may have been transformed from aryltetralin lignans by means of oxidative cleavage followed by ring closure.