New thiazole, pyridine and pyrazole derivatives as antioxidant candidates: synthesis, DFT calculations and molecular docking study

Novel heterocyclic compounds containing pyrazole, thiazole and pyridine moieties were designed and prepared based on the condensation reaction between 1,3-thiazole or aminopyridine derivatives and 1H-pyrazole,3,5-dimethyl-1H-pyrazole or 1,2,4-triazole. Their structures were confirmed with FTIR, ¹H and ¹³C NMR analyses. DPPH scavenging assay was used to evaluate their antioxidant potential. The ligand 4 showed the best antioxidant activity with an IC₅₀ = 4.67 μg/mL, while IC₅₀ values of the other compounds were found to be ranging from 20.56 to 45.32 μg/mL. DFT and molecular docking studies were performed in order to gain better insights and to understand the relationship between the structures of the studied compounds and their antioxidant activities. The results obtained revealed a good agreement between the experimental and the theoretical findings.