Integrated exploration of molecular structure, quantum chemical properties, molecular docking, and antioxidant activity of 4-(2-hydroxyanilino)pent-3-en-2-one

Abstract

Schiff bases are crucial intermediates in organic chemistry. They are used to introduce carbon–nitrogen double bonds in organic molecules. In this study, 4-(2-hydroxyanilino) pent-3-in-2-one (L) was synthesized from the reaction of 2,4-pentanedione and 2-aminophenol. The structure of L was confirmed through analytical and spectroscopic data. In addition, its thermal stability was examined using thermogravimetric and differential thermal analysis. In the gas phase, investigations of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) revealed an energy gap (ΔE) of 3.9304 eV. The antioxidant capacity of L was assessed using various techniques, including hydroxyl radical scavenging, scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH), β-carotene bleaching, and scavenging of 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS). The synthesized Schiff base displayed significant antioxidant activity, with a half-maximal inhibitory concentration (IC50) of 19.8 µg/mL in the DPPH assay, 0.14 µg/mL in the ABTS assay, and 59.6 μg/mL in the hydroxyl radical scavenging assay. The bioactivity of the 4-(2-hydroxyanilino) pent-3-in-2-one was confirmed by the DFT study, and the MEP analysis indicates the reactivity of nitrogen and oxygen atoms. Docking studies and wave function analyses were conducted to provide further insights into the compound’s potential applications in the pharmaceutical field.