2-NAPHTHALENESULFONIC ACID, 5,6'-IMINOBIS(1-HYDROXY- 5,6'-Iminobis(1-hydroxy-2-naphthalenesulfonic acid) 73816-77-0 Bis-(5-hydroxy-7-sulfo-2-naftyl)amin [Czech] Kyselina 6,6'-iminodi-1-naftol-3-sulfonova [Czech] Kyselina di-I [Czech]