The synthesis of new heterocyclic compounds containing 3,5-diphenyl-1h-1,2,4-triazole ring

In this study, 1-(4-substitutedbenzyl)-3,5-diphenyl-1H-1,2,4-triazoles (60-64) were synthesized starting from 3,5-diphenyl-1H-1,2,4-triazole (46). Treatment of compound 46 with ethyl bromoacetate obtained ethyl(3,5-diphenyl-1H-1,2,4-triazole-1-yl)acetate (76), which was converted to 2-(3,5-diphenyl-1H-1,2,4-triazole-1-yl)acetohydrazide (77) by treatment with hydrazine hydrate in 1-butanol. 2-[(3,5-diphenyl-1H-1,2,4-triazole-1-yl)acetyl]4-methyl/phenyl thiosemicarbazides (106 and 107) was prepared by the reaction of compound 77 with isothiocyanate derivatives. Cyclization of 106 and 107 with 2N NaOH resulted in the formation of 5-[(3,5-diphenyl-1H-1,2,4-triazole-1-yl)methyl]-4-methyl/phenyl-2,4-dihydro-3H-1,2,4-triazole-3-thiole (108 ve 109). Treatment of 108 and 109 with benzyl bromide derivatives (55-59) gave 5-[(3,5-diphenyl-1H-1,2,4-triazole-1-yl)methyl]-3-(4-substitutedbenzyl)thio-4-methyl/phenyl-2,4-dyhidro-3H-1,2,4-triazoles (126-135). Twenty one new heterocyclic compounds containing 3,5-diphenyl-1H-1,2,4-triazole ring were synthesized and characterized by IR, 1H NMR, 13C NMR and mass spectra.