[Contribution to the analysis of the hypoglycaemic agent tolbutamide. Part 2 (author's transl)]

The chemical identification reaction for tolbutamide (USP 1975) involves its hydrolysis by sulphuric acid with the formation of n-butylamine. This amine then reacts with diazotised p-nitraniline to give 8 red or yellow coloured compounds. A radicalic and an ionic mechanism for their formation, which are partially interrelated, are discussed. Other oral sulphonamide-hypoglycaemic agents give a positive result with this identification reaction.