Chemical constituents of gentianaceae XXVIII: flavonoids of Enicostemma hyssopifolium (Willd.) Verd.

The whole plant of Enicostemma hyssopifolium (Willd.) Verd. (Gentianaceae) was collected at different growth stages and was shown to contain seven flavonoids: apigenin (I), genkwanin (II), isovitexin (III), swertisin (IV), saponarin (V), 5-O-glucosylswertisin (VI), and 5-O-glucosylisoswertisin (VII). Compounds VI and VII previously were unreported in nature. The yields of the flavonoids varied with the growth stage. The biochemical and chemotaxonomic significance of these results is appraised.