1-Acetamido-8-naphthol-3,6-disulfonic acid 134-34-9 16698-16-1 2,7-Naphthalenedisulfonic acid, 4-(acetylamino)-5-hydroxy- 4-(Acetylamino)-5-hydroxy-2,7-naphthalenedisulfonic acid 4-Acetamido-5-hydroxynaphthalene-2,7-disulphonic acid EINECS 205-139-2