2,7-Naphthalenedisulfonic acid, 4-hydroxy-5-(((2-hydroxyphenyl)methylene)amino)- 32266-60-7 4-Hydroxy-5-(((2-hydroxyphenyl)methylene)amino)naphthalene-2,7-disulphonic acid 5941-07-1 Azomethine H EINECS 250-975-3