Nano-synthesis approach, elaborated spectral, biological activity and in silico assessment of novel nano-metal complexes based on sulfamerazine azo dye

Abstract

Novel mono- and homo bi-nuclear chelates of sulfamerazine-resorcinol azo-dye ligand (H3L) for pharmaceutical applications were acquired by coupling of sulfamerazine diazonium salt with resorcinol. The structural formula of H3L and its formed chelates with Cu(II), Ni(II), Zn(II), Cd(II), Hg(II), ZrO(II) and Ce(III) were investigated using elemental analysis and thermogravimetric analysis, Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (1H NMR), UV–Vis, ESR, transmittance electron microscope (TEM), X-ray powder diffraction (XRD), magnetic moment and molar conductance. The obtained results indicated that H3L was chelated with Cu(II) ions in a monobasic di-dentate linked to the metal ion via azo nitrogen, and dehydrogenated phenolic oxygen in the ortho-position. The remaining complexes, in addition to the previous coordination centers, H3L chelated with the metal ions through one N-atom of pyrimidine ring, and deprotonated sulfonamide oxygen in dibasic bimetallic mode. Based on the spectral and analytical results the formed complexes attained various geometry depending on the typed of chelated element. Where Ni(II), Zn(II), Cd(II) and Hg(II) complexes attained tetrahedral geometry, ZrO(II) got square pyramidal geometry, Cu(II) complex accomplished square planar arrangement and Ce(III) complex had octahedral configuration. Applying Coats-Redfern equations, the activation thermo-kinetic parameters (E*, ΔH*, ΔS*, and ΔG*) for different degradation stages the inspected chelates were computed from TGA graphs. Overwhelmingly, the antimicrobial and antitumor efficiency were investigated for the prepared complexes, which showed high activity after complex formation. The anticancer activity against human liver carcinoma cells (HepG-2) showed promising results, Ni(II) complex exhibited the highest anticancer activity (IC50 = 4.68 µg/mL). Molecular docking simulations were also achieved to evaluate inhibitory efficacy theoretically on the oncogenic protein H-ras (PDB ID: 121P) and protein of liver cancer 2 (PDB ID: 2JW2).