N-BENZOYL H ACID 4-(benzoylamino)-5-hydroxy-7-naphthalenedisulfonicacid 4-(benzoylamino)-5-hydroxynaphthalene-2,7-disulphonic acid 4-formamido-5-hydroxynaphthalene-2,7-disulfonic acid 4-Benzamido-5-hydroxy-2,7-naphthalenedisulfonic acid 5-Hydroxy-4-(benzoylamino)-2,7-naphthalenedisulfonic acid 4-benzamido-5-hydroxynaphthalene-2,7-disulfonic acid 2,7-Naphthalenedisulfonic acid, 4-(benzoylamino)-5-hydroxy-