Synthesis and Corrosion Inhibition Performance of Bisoprolol Drugs

4-3-［(1-methylethyl)amino-2-hydroxy］propoxy phenylacetamide(Atenolol) and 1-［(1-methylethyl)amino］-3-(1-naphthalenyloxy)-2-propanol(Propranolol) were synthesized form 4-hydroxyphenylacetamide and 1-naphthol, respectively. The corrosion inhibition and mechanism of the drugs for mild steel in 1.0 mol·L-1 H2SO4 at 25 ℃ were studied using polarization curves and electrochemical impedance spectroscopy (EIS). The electron density of various atoms and the energy of highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) in the molecules were computed by quantum study. The electrochemical results reveal that the two drugs are mix-type inhibitors which mainly inhibit the anodic process. The results of the quantum chemistry calculation show that propranolol has higher energy of the HOMO and lower energy of the LUMO. All the results conclude that propranolol has better inhibition performance than atenolol under the same conditions.