The molecule is a dihydroxyanthraquinone that is 1,6-dihyroxy-9,10-anthraquinone which is substituted by a methyl group at position 3 and a methoxy group at position 8. It derives from an emodin. It is a conjugate acid of a questin-2-olate.
1,6-dihydroxy-8-methoxy-3-methylanthracene-9,10-dione