Synthesis of Certain Thiazolo{3,2-a]beenzimidazole Derivatives of Potential Hypoglycemic Activity

The this is prefaced abrief account on diabetes . treatment of diabe- tes , quaternary salts as hypoglycemic agents and the chemistry of thiazo- {3,2-a} benzimidazoles.Because of the hypogly cemic activy reported for certain quaternary salts , it was of interestto synthesize certain thiazooe [3,2- albenzimidazolium salts to investigated as potential hypoglycemic agents .5,6- Dimethbenzimidazoline -2- thione, the key intermediate was syn- thesized by the reaction of 4,5- dimethyl –o- phenylenediamine with carbon di- sulfide in presence of potassium hydroxide .Phenacy bromides were synthesized by brominating of the aropriate acetophenone derivatives in ether – dioxin.5-6- Dimethyl -2-(p-(un) substituted phenacylthio ) benzimidazoes were synthesized by the rection of 5,6- dimethybenzimidazoline -2- thione with the appropriate phenacyl bromide in aqueous sodium hydroxide / ethanol solution.3-Aryl -6,7 – dimethylthiazoloa [3,2- albenzimidazoes were synthesized by cyclodehydration of 5,6 dimethyl -2- (p-(un)substitutedphenacylthio )benzimi- dazoles in polyphosphoricOr glacial acetic acid .3-aryl -6,7- dimethy -9 substitutedthiazolo [3,2-a] benzimidazoium salts were synthesized by refluxing the 3-aryl-5,6- dimethylthiazolo [3,2-a] benz- imidazoles with the appropriate quaternizing agent in chloroform containing DROPs of actonitrile.