8-Carboxy-6-sulfamyldibenz[b,f][1,4]oxazepines and -thiazepines as potential high-ceiling diuretics

The synthesis of several 8-carboxy-6-sulfamyldibenz[b,f][1,4]oxazepines and -thiazepines is described. The results of diuretic screening lend support to the thesis that activity is strongly dependent on the conformational mobility of 4-substituents in the 3-amino-5-sulfamylbenzoic acids.