Theoretical prediction: Although metabolism of anthraquinone in mammals has not yet been studied, a metabolic pathway analogous to anthracene may be anticipated. Antrhaquinone (1) may be oxidized by cytochrome P450 to the correponding 1,2-epoxide (2), which is either hydrolyzed by epoxide hydrolase to 1,2-dihydro-9,10-dioxoanthracene-1,2-diol (3) or isomerized to 2-hydroxyanthraquinone (5). Both products may be excreted in urine as conjugates with glucuronic acid or sulfate (4) and (6).
Further degradation of 2-hydroxyanthraquinone (5) see metabolism page of 2-hydroxyanthraquinone.