133-78-8 3-14-00-02210 (Beilstein Handbook Reference) 4-Amino-o-toluenesulfonic acid 5-Aminotoluene-2-sulphonic acid BRN 2098723 EINECS 205-120-9 Kyselina 3-toluidin-6-sulfonova [Czech] o-Toluenesulfonic acid, 4-amino-