Microwave synthesis of 2,3,5-trisubstituted-1,3-imidazolidin-4-ones bearing 1,3,4-oxadiazole moiety and preliminary evaluation of their antibacterial activity

摘要

5-(4-aminophenyl)-2-thiol-1,3,4-oxadiazole 2 has been prepared through cyclization of 4-aminobenzoyl hydrazide 1 with carbon disulfide in the existence of (KOH) in ethyl alcohol. Oxadiazole derivative 2 has been transformed to analogous diazonium salt that was straightaway treated with salicylaldehyde as coupling reagent to yield the initiator aldehyde 3. Condensation of aldehyde 3 with anilines consisting (p-bromoaniline, p-chloroaniline, p-nitroaniline, m-nitroaniline, p-methoxyaniline and p-hydroxyaniline) using microwave irradiation technique in ethyl alcohol to give six imines 4a-f. Treatment of the resulting imines 4a-f with tyrosine in microwave oven produced six imidazolidin-4-ones 5a-f consisting 1,3,4-oxadiazole unit. Investigation of antibacterial activity for the target compounds has been taken place on bacteria, Staphylococcus aurous and Escherichia coli. Outputs evinced that the synthesized imidazolidin-4-one (compound 5e) exhibited better activity to gentamycin athwart positive bacteria. Meanwhile, the imidazolidin-4-ones (5a, 5d, 5e and 5f) expressed greater verve athwart negative bacteria in comparison with that of the reference antibiotic (Gentamycin).