JPS5136468

Procedure for the preparation of benzimidazole derivatives of the general formula I **(See formula)** wherein R1 means an ortho-hydroxyphenyl group, a para-chlorophenyl group or a para-fluorophenyl group and R2 means an alcohol radical with 2 to 4 carbon atoms, as well as its salts with physiologically compatible acids, characterized in that, a) a compound of the general formula II is condensed **(See formula)** wherein R3 signifies an ortho-hydroxyphenyl group, an ortho-acyloxyphenyl group, an ortho-benzyloxyphenyl group, a para-chlorophenyl group or a para-fluorophenyl group and X signifies a halogen atom, an alkylsulfonyloxy radical or an arylsulfonyloxy radical, with an N-alcoholicpiperazine of the general formula III **(See formula)** where it has the meanings mentioned entities; or b) a compound of the general formula IV is condensed **(See formula)** wherein R3 has the aforementioned meanings, with a piperazine derivative of the general formula V **(See formula)** wherein R2 has the aforementioned meanings, and Y means a carboxyl group, an alkoxycarbonyl group, a chlorocarbonyl group or an alcohol-formimido group; or c) a compound of the general formula VI is cyclized **(See formula)** wherein R2 and R3 have the aforementioned meanings; or d) a compound of the general formula VII is condensed **(See formula)** wherein R2 has the aforementioned meanings, with a compound of the general formula VIII X-CH2R3 (VIII), wherein R3 and X have the aforementioned meanings, an acyloxy group or a benzyloxy group optionally present in the substituent R3 is separated, and if desired the benzimidazole derivatives of the general formula I, obtained in this way, are transformed with acids Physiologically compatible in its salts. (Machine-translation by Google Translate, not legally binding)