2-Mercaptobenzimidazole Based Hydrazone Derivatives as Potential Antioxidant and α-Glucosidase Inhibitors

Background: Schiff bases are organic compounds and play a vital role in making biologically active compounds in various fields of chemistry. It shows antioxidant, antidepressant, antimalarial, anti-inflammatory, antiglycation, and antimicrobial activity. Objective: Our current study is focused on synthesizing thirty-four 2-mercaptobenzimidazole (MBI) based novel hydrazone derivatives (9-42) which were examined for antioxidant free radical scavenging activity via both 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2) assay and explored their alpha-glucosidase inhibitory potential at various concentrations. Methods: Multistep reactions were involved in the synthesis of 2-mercaptobenzimidazole-based hydrazone derivatives. All steps of the reaction were carried out under different conditions through a reflux condenser to get the final target products, and the reaction was monitored regularly in each step through thin layer chromatography (TLC). The antioxidant and α-glucosidase inhibition assay was performed. Results: Obtained results of antioxidants confirmed that compounds 42 (IC50 = 27.21μg/mL), 36 (IC50 = 27.90μg/mL), 23 (IC50 = 28.10μg/mL) and 35 (IC50 = 45.60μg/mL) possess excellent potential activity compared to standard ascorbic acid having (IC50 = 60.15 μg/mL) in DPPH assay. While in the case of H2O2 three compounds 38 (IC50 = 51.45 μg/mL), 15 (IC50 = 53.50 μg/mL), and 42 (IC50 = 60.42 μg/mL) showed excellent activity as compared to standard Gallic acid having (IC50= 60.67 μg/mL). In the screened compounds against alpha-glucosidase, compound 14 (IC50 = 162 μg/mL) was found to be the most active in the whole series. Another active compound 42 (IC50 = 237μg/mL) possessed moderate inhibitory potency against α-glucosidase enzyme. Conclusion: The different biological activities of these novel compounds may be due to different groups in the main skeleton of 2-mercaptobenzimidazole. Further experimental analysis and assessment of these compounds are important because they may lead to better antioxidants used in foods, cosmetics, and health-related products and act as antidiabetic drug development.