Sorocein L and sorocein M: two Diels-Alder type adducts from Sorocea ilicifolia.

Two new Diels-Alder type adducts, named sorocein L (1) and sorocein M (2), together with the known kuwanon J and mulberrofuran O, were isolated from the methanolic extract of the roots of Sorocea ilicifolia. Sorocein L shows the same substitution pattern of sorocein M and corresponds to its ketalized derivative.