trisodium 4-hydroxy-3-[[4-[(2-hydroxy-7-sulphonato-1-naphthyl)azo]-2,5-dimethoxyphenyl]azo]-8-[(4-sulphonatobenzoyl)amino]naphthalene-2-sulphonate

4-Hydroxy-3-[[4-[(2-hydroxy-7-sodiooxysulfonyl-1-naphtyl)azo]-2,5-dimethoxyphenyl]azo]-8-[(4-sodiooxysulfonylbenzoyl)amino]-2-naphthalenesulfonic acid sodium salt