New copper (II) complexes derived from azo pyridone dyes: Structure characterization, thermal properties, and molecular docking studies

Abstract

Two azo dye ligands, bearing different substituents (chlorine atom or methoxy group) in the para‐position of the phenyl ring, were employed for the synthesis of two Cu(II) chelates. Full structural affirmation of complexes was assessed. X‐ray diffraction measurements revealed that the coordination geometry for Cu atoms in both complexes is square‐pyramidal with a ligand:metal ratio of 2:1 where dyes behave as monobasic bidentate ligands. Thermogravimetric analyses of the complexes and their starting dyes were performed to study their thermal stabilities and decomposition behavior confirming the thermal stability of both dyes and complexes. Antioxidative activity of the complexes has been assigned and compared with their parent ligands revealing that the presence of the electron–donor, methoxy group, in the phenyl ring, in both dye and complex, is responsible for the activity (IC50 values of 1.54 for the dye and 1.30 mM for the complex). It should be stated that the complexation of the methoxy‐substituted dye leads to enhanced antioxidative activity concurrent to a standard antioxidant molecule of ascorbic acid, making this molecule a promising antioxidant agent. Docking study with vascular endothelial growth factor receptor 2 and Aurora kinase A proteins indicate that complexes exhibit higher binding affinities to proteins than the starting ligand dyes. The most promising structure exhibiting the best docking potential toward both proteins is the complex‐bearing methoxy group. The presented results represent a promising start for further investigations of these compounds as potential therapeutic candidates for the treatment of various types of cancer.

Novel Synthesis of N–N Azo and Hydrazine Phenyl Ligand Derivatives for Copper(II) Complex Bio-Active Application

“…More interestingly, the azo-pyridone moiety containing ligands and their copper(II) complexes are becoming biologically promising where Lađarević and coworkers also reported on a similar work by ligand substituent tuning strategy [31]. In this work, both complexes, the chloride substituted (Cu(II)-Cl) and methoxy substituted (Cu(II)-OCH 3 ) was found to be promising compounds for the treatment of various types of cancer which could be considered as potential therapeutic candidates.…”

“…Idemudia and coworkers reported air-stable keto imine form of acylpyrazolone phenylhydrazones based ligands prepared by condensation of 4-acetyl and 4-benzoyl pyrazolone with dinitrophenylhydrazine as well as phenylhydrazine namely; benzoylphenylhydrazone (Bmpp-Ph), acetyldinitrophenylhydrazone (Ampp-Dh), as well as benzoyldinitrophenylhydrazone (Bmpp-Dh) and their transition metal complexes (Cu(II), Mn(II), Co(II), and Ni(II)) (Figure 14) [43]. All the complexes are under octahedral geometry and exhibited better biological activity than their respective [31].…”

“…Optimized molecular structure of the copper(II) complexes of Cu(II)-Cl (a) and Cu(II)-OCH 3 (b). Best docking poses with interacting residues, as well as intermolecular interactions of CuL-OCH 3 complex with VEGFR-2 (c) and Aurora kinase A (d)[31].…”