Synthesis, characterization, electrochemical behavior and antioxidant activity of new copper(II) coordination compounds with curcumin derivatives

Five new copper(II) coordination compounds were prepared by template synthesis, using curcumin, 2-hydrazinobenzothiazole and metal salt (copper chloride, bromide, acetate and nitrate) in 1:2:1 and 1:2:2 molar ratio. The complexes were characterized by elemental and thermogravimetric analysis, IR, UV-Vis and mass spectroscopic methods and cyclic voltammetric studies. On the basis of physico-chemical measurements the following formulae have been assigned to the complexes: [Cu(H2L)(H2O)(2)]Cl-2 center dot H2O, [CuL]center dot H2O, [Cu(H2L)(H2O)Br]Br center dot 5H(2)O, [Cu2L(H2O)(4)](NO3)(2)-center dot 2H(2)O and [Cu-2(H2L)(NO3)(4)]center dot H2O, where H2L is the hydrazone ligand formed in the reaction conditions. Metal complexes were tested for antioxidant activity by photochemiluminescence and this activity was quantified by comparison with TROLOX (R), as standard. The results show that all complexes are more potent antioxidant agents than curcumin. (C) 2019 King Saud University. Production and hosting by Elseivier B.V.