Synthesis, characterization, molecular docking, biological activity, and DNA cleavage studies of Cu(II), Co(II), Ni(II), Mn(II), and Cd(II) Schiff base complexes

Abstract

Metal complexes of Schiff base ligand 4-((Z)-(4-nitrophenylimino)methyl)benzene-1,3-diol (H 2 L) derived from condensation of 2,4-dihydroxybenzaldehyde and p-nitroaniline were synthesized and characterized by elemental analysis, IR, 1 H NMR spectra, magnetic moment, molar conductance, and ultraviolet (UV)-Visible and thermal analysis. The complexes were proposed to have the formula [M (HL)(OAc) 2 ] where M = Cu (II), Co(II), Ni(II), Mn(II), and Cd(II). The Fourier transform infrared (FT-IR) spectra showed that ligand is coordinated to the metal ions in bidentate manner with donor sites of the azomethine-N, phenolic-OH. The synthesized Schiff base ligand and its metal complexes (1)-( 5) were screened for their antibacterial activity. Antifungal activities were determined against Fusarium oxysporum, Aspergillus niger, and Candida albicans. Complex (5) showed a high potential cytotoxic activity against growth human lung cancer tumor cell lines. The DNA cleavage properties of the ligand and its complexes have been investigated by gel electrophoresis whose results showed that the Cu(II) complex has a significant oxidative cleavage among other complexes. Addition of H 2 O 2 to the cleavage reaction enhanced the complete DNA degradation for Cu(II) and Co(II) complexes and DNA cleavage for Mn(II) complex. Molecular docking study between the ligand and the receptors (Escherichia coli [3t88], Staphylococcus aureus [3q8u],prostate cancer [2q7l Hormone], breast cancer [1jnx Gene regulation], lung cancer [1x2j], and colon cancer [2hq6]) was carried out, and it was found that the ligand is an efficient compound for all these receptors.