, smoke Brown G , hydroxylizaric acid , and C.I. 58205 . It is a minor component of the classical lake pigment "madder lake" or Rose Madder . Read more... Edit at Wikipedia... Other names 1,2,4-Trihydroxy-9,10-anthraquinone (IUPAC Name); 1,2,4-Trihydroxy-9,10-anthracenedione; Purpurin References Please add any relevant references here. Retrieved from " http://www.rsc.org/learn-chemistry/wiki/Substance:1,2,4-Trihydroxyanthraquinone "