Novel Sulfonate Derivatives Functionalized with Triazole-Hydrazone Moieties: Synthesis, Characterization, DFT,...

In this study, a new series of (E)-4-((2-(2-(4-amino-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)acetyl)hydrazono)methyl)phenyl 4-halogenobenzenesulfonates (3a-3d), where 3a = F, 3b = Cl, 3c = Br, and 3d = I, were successfully synthesized via a straightforward synthetic route. The structures of the obtained compounds were fully characterized and confirmed by spectroscopic techniques, including FT-IR, ¹H NMR, and ¹³C NMR, as well as LC-MS/MS analysis. 1,2,4-triazole-based hydrazone derivatives (3a-3d) were investigated using IR and NMR spectroscopy and DFT calculations. Intermolecular interactions, HOMO-LUMO, dipole moment, polarization, first-order hyperpolarizability, and molecular electrostatic potential studies on the molecules were examined. The HOMO and LUMO energy gap study supports the charge transfer probability in the molecules. These were conducted to investigate the reactivity and stability of heterocyclic molecules in bioactivity analysis. Electron density mapping within the molecular electrostatic potential plot and electrostatic potential representation within the iso-surface plot evaluated the concept of charge distribution in the molecule as nucleophilic reactions and electrophilic regions. The predicted nonlinear optical (NLO) properties of the molecules are much greater than those of urea. The results obtained from these investigations collectively provide evidence that the molecules possess nonlinear optical applications. Novel triazole-hydrazone-functionalized aryl sulfonate derivatives (3a-3d) were evaluated for their anticancer potential against a panel of brain and non-brain cancer cell lines. Compound 3b exhibited the most favorable overall biological profile, displaying potent activity against SH-SY5Y neuroblastoma (GI = 7.59 μM) and U87MG glioblastoma cells (GI = 13.85 μM), together with the lowest toxicity toward normal FL fibroblasts (GI = 62.02 μM). Compounds 3c and 3d demonstrated remarkable potency against IDHmut-U87 glioma cells (GI = 3.87 and 3.27 μM, respectively), although their selectivity toward cancer cells was limited. DNA degradation studies revealed substantial fragmentation, particularly in C6 and SH-SY5Y cells, while migration assays indicated reduced cellular motility. Molecular docking studies identified compound 3b as the strongest PI3Kα binder, supporting a possible. In addition, the antimicrobial activities of compounds 3a-3d were evaluated against selected Gram-positive and Gram-negative bacteria as well as Candida species using the broth microdilution method. The compounds exhibited measurable antimicrobial effects with MIC values ranging from 156 to 625 µg/mL, showing moderate growth inhibition against the tested microorganisms. Although the observed activity was lower than that of the reference antimicrobial agents, the results indicate that these triazole-hydrazone derivatives possess a detectable level of antimicrobial activity and provide a basis for further structural optimization. Collectively, the results suggest that compound 3b represents the most promising lead structure due to its balanced combination of potency, selectivity, and predicted target engagement. Molecular docking was performed to evaluate the binding potential of newly synthesized triazole derivatives (3a-3d) against PI3Kα. The docking protocol was validated by re-docking alpelisib, yielding an RMSD of 0.64 Å. Among the tested compounds, 3b showed the most favorable binding energy (-9.94 kcal/mol) and estimated Ki value (52.13 nM), consistent with its superior in vitro activity. Its interactions with key PI3Kα residues, including Val851, Ser854, Met922, and Asp933, support a stable binding mode within the ATP-binding pocket. In silico ADME and toxicity analyses suggested acceptable drug-likeness characteristics, absence of major hepatotoxic, mutagenic, and carcinogenic liabilities, and moderate predicted acute toxicity profiles. These findings suggest that 3b is the most promising derivative for further validation.