o-Sulfo-phenylhydrazin, sulfophenylhydrazine, 2-diazanylbenzenesulfonic acid, hydrazinobenzenesulfonic acid, Benzenesulfonic acid,2-hydrazino, o-Hydrazinobenzenesulphonic acid, o-Hydrazinobenzenesulfonic acid, 2-Hydrazino-benzolsulfonsaeure, sulphophenylhydrazine, Benzenesulfonic acid,o-hydrazino