VERFAHREN ZUR HERSTELLUNG VON NEUEN 4,5,6,7- TETRAHYDROIMIDAZO (4,5-C)PYRIDINDERIVATEN UND DEREN SAEUREADDITIONSSALZEN

New 4,5,6,7-tetrahydroimidazo-¢4,5-c!-pyridine derivatives are disclosed, and more particularly derivatives of Formula I: I wherein R1 is hydrogen or an alkyl having from 1 to 4 carbon atoms; R2 is hydrogen, an alkyl having from 1 to 4 carbon atoms, a cycloalkyl having from 3 to 6 carbon atoms, phenyl, furyl or thienyl group; R3 is hydrogen, a saturated or unsaturated straight or branched alkyl having from 1 to 4 carbon atoms, a cycloalkyl having from 3 to 6 carbon atoms, or phenyl and X is O, S or NR4 where R4 is hydrogen, or a cyano group; or pharmaceutically acceptable acid addition salts thereof. Also disclosed is a process of preparing these compounds which comprises condensing an appropriate 4,5,6,7-tetrahydroimidazo ¢4,5-c!-pyridine with an appropriate alkyl isocyanate, alkyl isothiocyanate or substituted S-methyl thiourea, preferably in a solvent such as ethanol, acetonitrile or dioxane, usually under reflux for from 4 to 12 hours. The products can be isolated by crystalization as free bases or as salts of pharmaceutically acceptable acids. The new compounds have proved to be well tolerated and to inhibit both the number of experimental ulcers and the gastric secretion in experimental animals. Thus, they should prove useful in the therapy of gastric and duodenal ulcers in man.