SMILES: C1=CC=C2C(=C1)C(=O)C3=CC(=C(C(=C3C2=O)O)O)S(=O)(=O)O
Description: The molecule is a dihydroxyanthraquinone that is 1,2-dihydroxyanthraquinone compound carrying an additional sulfo substituent at the 3-position. The monosodium salt is the biological stain 'alizarin red S'. It has a role as a histological dye. It is a dihydroxyanthraquinone and an organosulfonic acid. It is a conjugate acid of a 3,4-dihydroxy-9,10-dioxo-9,10-dihydroanthracene-2-sulfonate.