Antioxidant properties, computational studies and corrosion inhibition potential of 3-hydroxy-1-(2-hydroxyphenyl)-5-(phenyl)-2,4-pentadien-1-one analogues

Abstract

Ten derivatives of (2Z,4E)-3-hydroxy-1-(2-hydroxyphenyl)-5-phenylpenta-2,4-dien-1-one were investigated for their antioxidant properties and corrosion inhibition potential. The compounds were screened for their antioxidant activity using the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging assay and the ferric reducing antioxidant power (FRAP) assay. The methoxylated analogues generally showed better antioxidant activity than the fluorinated analogues. The compounds were screened for drug-likeness properties using in silico techniques. They were found to obey the Lipinski rule of five, which indicated promising absorption or permeability properties through biological membranes. The flexible-ligand docking studies were performed using Auto Dock 4.2 with protein tyrosinase (PDB code: 3NM8). Furthermore, the methoxy derivatives exhibited relatively high binding energies, indicating the possibility of greater interactions with proteins. The compounds were also tested for possible anticorrosion properties using the potentiodynamic polarization and electrochemical impedance spectroscopy techniques. All the compounds showed appreciable corrosion inhibition efficiency for mild steel in 1M HCl. These compounds are mixed-type inhibitors. The adsorption of the compounds on a mild steel surface obeyed the Temkin adsorption isotherm and the derived adsorption thermodynamic parameters indicate a spontaneous and chemical adsorption process.