author(s) :

The family Aristolochiaceae, a dicotyledon, comprises 12 genera and 475 species (Boulos, 1999).
The family Aristolochiaceae is characterized by the presence of aristolochic acid (Figure 1, a mixture of structural-related nitrophenanthrene carboxylic acid derivatives), found primarily in the genus Aristolochia. Asatone [1, a polycyclic neolignan derivative (3’R,6’S)-(1β,2β)-2,3,5′,6′-tetrahydro-3,3,3′,5,5′,5′-hexamethoxy-2,6′-cyclo-1,3′-neolignan-8,8′-diene-4,4′(3’H)-dione] was found in 4 Asarum species of section Aschidasarum, 3 of section Euheterotropa, and in 1 of section Bicornes (Hayashi et al., 1976).
Isoasatone A (2), in addition to asatone, were isolated from Asarum macranthum (Lin et al., 1995).