Co (II), Ni (II), and Cu (II) complexes of 4,6‐bis(2‐hydroxynaphthalen‐1‐yl)methyl‐ene)hydrazono)ethyl)benzene‐1,3‐diol: Synthesis, spectroscopic, biological, and theoretical studies

Abstract

AbstractA new hydrazone ligand 4,6‐bis(2‐hydroxynaphthalen‐1‐yl)methyl‐ene)hydrazono)ethyl)benzene‐1,3‐diol (H4L; DHNAPH) was synthesized by the reaction of 4,6‐bis(1‐hydrazonoethyl)benzene‐1,3‐diol (NH2DAR) with 2‐hydroxy 1‐naphthaldehyde. Co (II), Ni (II), and Cu (II) complexes ([M2L(H2O)6].nH2O.mEtOH (M = Co, Ni or Cu;n= 0.5 or 1; andm= 0.5 or 0) of DHNAPH have been successfully synthesized. Characterization of DHNAPH and its complexes was performed by analytical, spectral (infrared [IR], mass, UV–Vis,1H NMR, and electron spin resonance [ESR]), powder X‐ray diffraction (XRD), magnetic susceptibility, molar conductivity, and thermal gravimetric analysis (TGA) techniques. The analytical data, magnetic moments, and spectral studies recognized octahedral geometries for DHNAPH complexes. DHNAPH acts as a bis (dibasic tridentate) via (C=Nazomethineand 2 OH) with metal in complexes. The XRD patterns for DHNAPH and its complexes indicate crystalline nature of DHNAPH and its Cu complex. DHNAPH has triclinic system, while copper‐DHNAPH has a tetragonal system with different unit cell parameters. Theoretical studies showed that there is a good relation between experimental IR data and theoretical calculation. The activity of DHNAPH and its complexes against Hepatocellular carcinoma, fungi, and bacteria has been tested. The new complexes are more active than DHNAPH, and the highest antitumor activity was given by copper (II) complex, which showed lower IC50than that of Cisplatin. The DNA binding of DHNAPH and Cu‐DHNAPH has been investigated. Molecular docking studies showed that all the tested compounds show good binding scores revealing good fitting in between the DNA strands. There is an agreement between docking data and DNA binding results.