SYNTHESIS, DIAGNOSIS, BIOLOGICAL ACTIVITY FOR SOME SUBSTITUTED TETRAZOLE DERIVED FROM METHYL 2-(p-TOLYL) BENZOATE

Abstract: Drug-resistant bacteria—including multidrug-resistant strains, persistent infections, and emerging pathogens—continue to spread rapidly, posing a serious threat to global public health. This situation highlights the urgent need to develop new, highly effective antimicrobial agents. In this study, a series of tetrazole derivatives were synthesized as potential antibiotic candidates. The compounds were prepared via the conventional reaction of hydrazones with sodium azide, using 4′-methyl-[1,1′-biphenyl]-2-carbohydrazide as the core scaffold. The synthesized compounds demonstrated notable antibacterial activity, particularly against Gram-positive Staphylococcus aureus, with several derivatives surpassing the reference antibiotic amoxicillin in potency. Compounds Li4, Li7, and Li9 showed inhibition zone diameters of 29, 21, and 24 mm, respectively, compared with the control. Against Gram-negative bacteria, compounds Li4 and Li9 also exhibited high activity, with inhibition zones of 26 mm and 24 mm, respectively—again exceeding the performance of the standard antibiotic. In contrast, compounds Li1, Li2, Li3, Li5, Li6, Li7, and Li8 displayed no detectable inhibitory activity against Escherichia coli. Spectroscopic measurements such as FT-IR and ¹H and ¹³C-NMR were used to confirm the formation of the prepared compounds.