SMILES: C1=CC(=CC=C1N=NC2=CC(=C(C=C2)N)S(=O)(=O)[O-])S(=O)(=O)[O-].[Na+].[Na+]
Description: The molecule is an organic sodium salt that is 4-aminoazobenzene-3,4'-disulfonic acid in which the protons of both of the sulfo groups have been replaced by sodium ions. It is used as a biological stain. It was formerly used as a food coloring agent (E105), but its use in food or drinks is now forbidden. It has a role as a histological dye. It contains a 4-aminoazobenzene-3,4'-disulfonate.