Also known as 1,2-dihydroxyanthraquinone, an important orange-red organic compound with a molecular formula C₁₄H₈O₄ and molecular weight 240.21 g·mol−1 , and melting point 279 to 283 °C. Used in the dyestuffs industry to produce red lakes. It occurs naturally in the root of the plant madder and may also be synthesized from anthraquinone.