7-Amino-4-hydroxy-3-[p-(p-sulfophenylazo)phenylazo]-2-naphthalenesulfonic acid

7-Amino-4-hydroxy-3-[4-(4-sulfophenylazo)phenylazo]-2-naphthalenesulfonic acid

1-Hydroxy-2-[[4-[(4-sulfophenyl)azo]phenyl]azo]-6-amino-3-naphthalenesulfonic acid

7-amino-4-hydroxy-3-[[4-[(4-sulphophenyl)azo]phenyl]azo]naphthalene-2-sulphonic acid