Green synthesis approach for novel benzenesulfonamide nanometer complexes with elaborated spectral, theoretical and biological treatments

New series of nano-sized bi-homonuclear Ce (III), ZrO (II), Sn (II), Pb (II), Cr (III), Fe (III) and Cu (II) complexes with 4-[(2,4-dihydroxybenzylidene)amino]-N-(1,3-thiazol-2-yl) benzenesulfonamide (H3L) were synthesized via green solid-state method. The structural and molecular formulae of all synthesized complexes were established based on variable spectral, analytical and theoretical implementations. FT-IR study confirms the coordination of H3L with metal ions through the Schiff base and sulfonamide centers in di-basic tetradentate mode. Thermal analysis, magnetic moment and electronic spectra are attributing to octahedral configuration around Ce (III), Cr (III) and Fe (III) centers, while with ZrO (II), Sn (II), Pb (II) and Cu (II) centers, acquired tetrahedral arrangement. TEM and XRD studies, represent the nanometer characters of most metal ion complexes. TGA curves are utilized to compute the activation thermo-kinetic parameters over different decomposition stages applying Coats-Redfern method. Theoretical implementation executed by Gaussian09 program exerted the structures for the best atomic orientation over whole molecules. QSAR data were achieved over Hyper Chem 8.1 program through molecular mechanics process. Docking complexes between free ligand and different protein receptors were obtained through AutoDock Tools 4.2. Antimicrobial, antifungal and antitumor activities of the metal complexes were studied in comparing with free ligand to assert their potential therapeutic uses. H3L, Ce (III), Fe (III) and Cu (II) complexes displayed high antibacterial activity near that of standard Gentamycin. Moreover, Cr (III) complex displayed highest cytotoxicity against human liver Carcinoma cell line (HEPG2).