Synthesis of 2-Substituted-6-amino-4, 5-dihydropyrimidine

The convenient synthesis of 2-substituted-6-amino-4, 5-dihydropyrimidine from the reaction of imidic ester with 3-aminopropionitrile was reported. Next, 2-phenyl- (V) and 2-(2-acylaminoethyl)-6-amino-4, 5-dihydropyrimidines were investigated to clarify their predominant form in the possible from the aspects of infrared spectra. Thus, it was found that V exists as the imino-form and 2-(2-acylaminoethyl)-6-amino-4, 5-dihydropyrimidines as the amino-form in the solid state. Further, it was described the synthesis of 3-acylaminopropionamidine possessing the heterocyclic ring for the purpose of potenciating the activity of benzamidopropionamidine which was studied previously.