Benzazol-Derivate, Verfahren zu deren Herstellung und pharmazeutische Zusammensetzungen, die sie enthalten

A compound of the formula : wherein R is aryl or a heterocyclic group, each of which may have suitable substituent(s), R is hydroxy, mercapto, lower alkylthio, sulfo, lower alkyl, amino or substituted amino, R is hydrogen, halogen or lower alkoxy, A is lower alkenylene, lower alkylene optionally substituted with hydroxy, or a group of the formula : -A min -Q-A sec -, in which A min is lower alkylene, A sec is lower alkylene or a single bond, and Q is O or S, and X is O, S, NH or N-R , in which R is lower alkyl, and a pharmaceutically acceptable salt thereof. A process for preparing the benzazole compounds is also described, together with a pharmaceutical composition comprising the same as an active ingredient. The compounds exhibit anti-ulcer activity and H2 - receptor antagonism, and are therfore useful in the treatment of, for example, gastritis, ulcers, zollinger-ellison syndrome, oesophagitis and upper gastrointestinal bleeding.