Nirvanol has been converted into colored derivatives. The latter contain a substituted aryl-azo-benzyl grouping attached to the nitrogen in the 3-position of the heterocycle. AUSTIN, TEXAS RECEIVED MAY 8, 1939 ... [CONTRIBUTION FROM THE RESEARCH LABORATORIES OF THE MALTBIE CHEMICAL Co. ] Sulfanilamido Derivatives of Heterocyclic Amines' ... BY RUSSEL J. FOSBINDER AND L. A. WALTER ... Since the discovery by Domagk2 that ...