Synthesis of imidazoline and imidazo[2,1-c][1,2,4]triazole aryl derivatives containing the methylthio group as possible antibacterial agents Original Research Article

1-Arylimidazolidine-2-thiones (1a–g) were synthesized by the condensation reaction of N-arylethylenediamines with carbon disulfide in xylene medium. Their further alkylation with methyl iodide led to the formation of some biologically active 1-aryl-2-methylthio-imidazolines (2a–g). The 7-(4-methylphenyl)-3-methylthio-5H-6,7-dihydroimidazo[2,1-c][1,2,4]triazole (4b) was obtained by the alkylation of the respective 7-(4-methylphenyl)-2,5,6,7-tetrahydroimidazo[2,1-c][1,2,4]triazol-3(H)-thione (3b) with methyl iodide. Antimicrobial activities of 1-aryl-2-methylthio-imidazolines (2a–g) and the 7-(4-methylphenyl)-3- methylthio-5H-6,7-dihydroimidazo[2,1-c][1,2,4]triazole (4b) are presented. All tested compounds showed MIC in the range of 11.0–89.2 μM. Compounds 2a,e were found to be equipotent to chloramphenicol in vitro, whereas 2a,c,e–g and 4b showed superior activity (MIC) to ampicillin.