Synthesis, in vitro enzyme inhibitory and antioxidant activities of novel S-Alkylated indole-1,2,4-triazole acyl hydrazones targeting type 2 diabetes
Phosphorus, Sulfur and Silicon and the Related Elements, 2026 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Publication Date: 2026
- Doi Number: 10.1080/10426507.2026.2732094
- Journal Name: Phosphorus, Sulfur and Silicon and the Related Elements
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Academic Search Ultimate (EBSCO), Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Keywords: 1,2,4-Triazole, molecular docking, S-alkylation, α-Amylase, α-Glucosidase
- Istanbul University Affiliated: Yes
Abstract
Managing postprandial hyperglycemia and oxidative stress remains a major hurdle in type 2 diabetes treatment. To tackle this dual challenge, we synthesized a novel series of S-alkylated indole-1,2,4-triazole acyl hydrazones, evaluating their antidiabetic and antioxidant capacities. Synthesis involved cyclizing thiosemicarbazide intermediates, followed by S-alkylation and condensation. Target structures were confirmed using FT-IR,1H/13C-NMR spectroscopy, LC-MS, and elemental analysis. Enzyme assays revealed striking activity differences depending on the terminal benzylidene substitutions. The p-bromo-substituted compound (4d) stood out as a potent α-glucosidase inhibitor, achieving 42.49% inhibition at 50 µM and significantly outperforming acarbose (27.50%). Meanwhile, the p-methoxy derivative (4c) was the most effective α-amylase inhibitor (IC50=17.33 µM). While final hybrids (4a-e) exhibited limited antioxidant effects, parent triazole-thione (2) and hydrazide (3) intermediates retained notable DPPH scavenging and reducing activities, respectively. SAR analysis indicated that bulky, lipophilic para-halogens on the benzylidene ring maximize α-glucosidase inhibition. Molecular docking against yeast isomaltase and human pancreatic α-amylase mirrored experimental data, pointing to E/Z geometric isomerism as a defining factor in target recognition. Docking showed that 4d locks into α-glucosidase active site through strong, configuration-dependent halogen bonds in both isomeric forms, whereas Z-configuration of 4c provides the exact spatial alignment for α-amylase pocket. Ultimately, compound 4d emerges as a strong, synthetically accessible lead for targeted antidiabetics.