A second pathway leading to anthraquinones in higher plants

The biosynthesis of chrysophanol (1,8-dihydroxy-3-methylanthraquinone) and emodin (1,6,8-trihydroxy-3-methylanthraquinone) has been studied in Rhamnus frangula and Rumex alpinus. Degradation of both anthraquinones after feeding 1-¹⁴C-acetate and 2-¹⁴C-acetate showed that these compounds are derived from acetate by linear combination. ¹⁴C-Shikimate and ¹⁴C-mevalonate were not incorporated.