SMILES: COC1=C(C=CC(=C1)C2=CC(=C(C=C2)N=NC3=C(C4=C(C=C(C=C4C=C3S(=O)(=O)O)S(=O)(=O)O)N)O)OC)N=NC5=C(C6=C(C=C(C=C6C=C5S(=O)(=O)O)S(=O)(=O)O)N)O
Description: The molecule is a ring assembly consisting of two 5-amino-4-hydroxy-3-[(2-methoxyphenyl)diazenyl]naphthalene-2,7-disulfonic acid units joined by a 4,4'-linkage. The tetrasodium salt is the histological dye 'Pontamine sky blue 5B'. It has a role as a histological dye, a fluorochrome and a carcinogenic agent. It is a member of azobenzenes, a bis(azo) compound, a member of naphthols, an aminonaphthalenesulfonic acid, an aromatic ether and a ring assembly. It is a conjugate acid of a Pontamine sky blue 5B(4-).