A process for the preparation of N-sulfamyl-propionamidine derivatives
申请人:CENTRO MARGA PARA LA INVESTIGACION S.A.
公开号:EP0356366A1
公开(公告)日:1990-02-28
N-sulfamyl-propionamidine derivatives are prepared by the reaction of 3-substituted-propionitriles with an oxonium hydrochloride, preferably of 1,4-dioxane, in the presence of sulfamide in a close system at pressures between 0.5 kg/cm and 4.0 kg/cm. These compounds are useful in the preparation of famotidine, an anti-ulcer agent.
The invention relates to new propionamidine derivatives of formula (I) ##STR1## wherein X is halogen, and to a process for their preparation. According to the invention compounds of the formula (I) are prepared by reacting a 3-halopropionitrile of the formula (III) ##STR2## wherein X is as defined above, with sulfamide of the formula (II) ##STR3## in the presence of a hydrogen halide. Compounds of the formula (I) are useful intermediates in the preparation of famotidine.
The invention relates to a new process for the preparation of N-sulfamyl-3-(2-guanidinothiazol-4-yl-methylthio)-propionitrile (famotidine) of the formula (I) ##STR1## by S-alkylation of 2-guanidino-thiazol-4-yl-methanethiol obtained from S-(2-guanidino-thiazol-4-yl-methyl)-isothiourea dihydrochloride of the formula (III) ##STR2## by in situ treatment with a base, which comprises carrying out S-alkylation with a N-sulfamyl-3-halopropionamidine of the formula (II) ##STR3## wherein X stands for halogen.