The title compound (P4) is studied for using as an interesting corrosion inhibitor for mild steel in acidic environment. The corrosion inhibition effect is investigated using weight loss, Tafel polarization, electrochemical impedance spectroscopy and DFT studies. The inhibitor showed 93% inhibition efficiency at 10-3 M concentration of P4. Potentiodynamic polarization suggests that it is a mixed type of inhibitor. Electrochemical impedance spectroscopy was used to investigate the mechanism of corrosion inhibition. The adsorption of this compound on mild steel surface obeys Langmuir adsorption isotherm. Quantum chemical studies were carried out in an attempt to rationalize this behavior.