Nano Schiff base and its metal complexes: Synthesis, Characterization tools, biological applications and molecular docking studies Walaa H. Mahmouda,b*, Ahmed M. Refaata, Gehad G. Mohameda, b a. Chemistry Department, Faculty of Science, Cairo University, Giza, 126103, Egypt b. Egypt Nanotechnology Center, Cairo University, 6th October City, Giza, El-Sheikh Zayed, 12588, Egypt

Abstract

A total of eight new metal complex derivatives of 4,4'-((1Z,1'Z)-(naphthalene-1,8-diylbis(azanylylidene))bis(methanylylidene))dibenzaldehyde, H2L with the metal ions Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) have been successfully prepared in alcoholic medium. The complexes obtained are characterized quantitatively and qualitatively by using micro elemental analysis, conductivity measurements, FT-IR spectroscopy, UV–Vis spectroscopy, mass spectroscopy, 1HNMR, magnetic susceptibility, thermal (TG/DTG) and SEM data to illuminate their structures. The data showed that the complexes had composition of MH2L type. From the spectral study, all the complexes obtained as monomeric structure and the metals center moieties are six-coordinated with an octahedral geometry. 1H NMR spectral data of the ligand (H2L) and its Zn(II) and Cd(II) complexes agreed well with the proposed structures. Thermogravimetric data (TG and DTG) were also studied. SEM analysis confirm the nano-structures of the ligand and some of its complexes. The preliminary in vitro antibacterial and antifungal screening activity revealed that complexes showed moderate activity against tested bacterial strains and slightly higher compared to the ligand (H2L). Anticancer activity of the ligand and its metal complexes were evaluated in human cancer (MCF-7 cells viability) and human normal melanocytes (HFB-4) cell lines. The binding between H2L with receptors of crystal structure of S. aureus (PDB ID: 3Q8U), crystal structure of sialidase NanC of Streptococcus pneumoniae (4YW4), receptors of breast cancer mutant oxidoreductase (PDB ID: 3HB5) and crystal structure of Escherichia coli (PDB ID: 3T88) were expected and set in details using molecular docking.