Synthesis, Molecular Docking and ADME Prediction of 1H-indole/5-substituted Indole Derivatives as Potential Antioxidant and Anti-Inflammatory Agents

Background: Inflammation is a protective biological process, but under extreme conditions, it can become highly dreadful to the body. Antioxidant and anti-inflammatory agents treat similar disease conditions as inflammation and oxidative stress commonly follow similar causative pathways. Objective: The goal of this study was to synthesize N-substituted indole derivatives with different heterocyclic moieties through propyl linker with the aim of getting highly potent anti-inflammatory and antioxidant agents. Methods: Synthesized compounds were analyzed by analytical techniques such as IR, H-1 NMR, C-13 NMR spectra, and mass spectrometry. Molecular docking and ADME calculation were employed on synthesized compounds to estimate their COX-2 enzyme inhibition and drug like properties, respectively. Antioxidant activity was evaluated by the DPPH assay and the reducing power assay. Selected derivatives were evaluated for anti-inflammatory activity at an acute (carrageenan-induced paw edema method) and chronic level (formalin-induced inflammation method) using indomethacin as a standard drug. Results: Herein, twelve indole derivatives (11a-c, 12a-c, 13a-c, and 14a-c) were synthesized. Among all, compound 12c was found to be the best inhibitor of the COX-2 enzyme as it displayed good interaction energy. Zero violations of Lipinski's rule were found in the ADME investigation, confirming the drug-like qualities of synthesized compounds. The compounds 11a and 12c were found to be the most potent as compared with standard ascorbic acid in antioxidant evaluation. From the collected results, compounds 12c and 13b were the most potent against acute and chronic inflammation. Conclusion: The novel synthetic indole derivatives could act as potent leads for the development of novel antioxidant and anti-inflammatory agents.