Fused triazoles derivatives have been prepared from the reaction of the starting material 4 with some electrophilicreagents. The structures of all new compounds have beenestablished on the basis of elemental analysis and spectroscopicdata. All the synthesized compounds have been screened for their antibacterial activity. 1,2,4-Triazole derivatives 4, 14 and 15 exhibited a good antibacterial activity compared with the standard antibiotic Gentamycin. The tautomeric equilibria of the compounds 4 and 15 thione and thiol form were studied by quantum chemical calculations semi-empirical (AM1, MNDO and PM3) and ab initio level (RHF/3-21G* and RHF/6-31G*) in the gas phase.
