Behzad Ghasemi
1*, Hamid Beyzaie
2, Hamidreza Majidiani
31 Faculty of Veterinary, University of Zabol, Zabol, Iran
2 Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran
3 Department of Medical Parasitology and Entomology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Abstract
Background: Bacillus cereus and Salmonella typhimurium are important human
pathogenic bacteria. The spread of strains of drug-resistant these pathogens
has encouraged researchers to identify and use novel antibacterial compounds.
In this research project, we studied antibacterial effects of some newly
synthesized thiazole, imidazolidine and tetrahydropyrimidine derivatives
against B. cereus and S. typhimurium.
Methods: 2-(E)-Cyano(thiazolidin-2-ylidene)thiazoles 1-4 and (imidazolidin or
tetrahydropyrimidin-2-ylidene)malononitriles 5-11 were synthesized. Then, the
disk diffusion and broth microdilution methods were applied to evaluate
antibacterial effects. Results were recorded as the minimum inhibitory
concentrations (MICs) and the growth inhibition zone diameters.
Results: The in vitro assessment of antibacterial effects showed that only
thiazole derivative 4 had considerable inhibitory effects against B. cereus and
S. Typhimurium, whereas the others didn't have so. The inhibitory effects of
thiazole derivative 4 against B. cereus and S. typhimurium were proven
according to the MICs 125 and 500 µg/mL and the growth inhibition zone
diameters 19.2±0.1 and 8.4±0.2 mm, respectively.
Conclusion: The antibacterial effects of thiazole, imidazolidine and
tetrahydropyrimidine derivatives were different, these effects were observed
only in thiazole derivative 4. It could be due to the presence of 4-thiazolone
ring in derivative 4, witch could reinforce these effects. After confirming
that compound 4 is bactericidal against B. cereus and S. typhimurium, further
studies can be accomplished on the determination of the cytotoxic and
therapeutic effects of this compound in laboratory animals.