Polyphenol oxidase activities by cobalt (II) complex with Benzopyran Derivatives, Synthetic, Characterization, Kinetics Study and Molecular Modeling Studies

Document Type : Original Article


Chemistry Department, Faculty of Science & Arts Al-Mukhwah, Al-Baha University, Al-Baha, Saudi Arabia


The Cobalt complex of 2-Amino-4-(2-chloro-5-nitrophenyl)-5,6,7,8-tetrahydro-7,7-dimethyl-5-oxo- 4H-chromene-3-carbonitrile)( CNB) was synthesized. The organic ligand CNB was previously synthesized using an environment friendly method using microwave irradiation. The cobalt complex cobalt (II)-CNB was characterized by different tools such as IR, electronic spectroscopy, elemental analysis, Thermal analysis and mass spectroscopy. The mode of metal binding shows that the cobalt binds with the ligand through the nitrogen atoms of the amino and cyanide groups. The cobalt complex cobalt (II)-CNB has been used in the homogenous oxidation of polyphenol 1, 2, 3-trihydroxybenzene in presence of a green oxidant H2O2 as biomimetic metalloenzymes. Kinetic parameters were calculate kcat 1.0971×10-5S-1, KM1.412 ×10-2 M, Vmax 7.68×10-4MS−1 and catalytic efficiency 7.769×10-7 .The oxidation reaction is inhibited by competitive inhibition by kojic acid with IC50 = 200 μM and molecular modeling studies geometrical optimization ,(HOMOs) ,(LUMOs and electrostatic potentials (ESP).


Main Subjects

Volume 63, Issue 12 - Serial Number 12
December 2020
Pages 5175-5181
  • Receive Date: 21 July 2019
  • Revise Date: 01 January 2020
  • Accept Date: 07 June 2020
  • First Publish Date: 09 June 2020