5-((2-Amino-4-hydroxy-5-((4-((4-nitro-2-sulphophenyl)amino)phenyl)azo)phenyl)azo)-4-hydroxy-3-((4-((4-nitro-2-sulphophenyl)amino)phenyl)azo)naphthalene-2,7-disulphonic acid, sodium salt 94021-35-9 EINECS 301-429-9