Abstract
The novel Schiff base ligand that is based on the condensation of 1-aminoquinolin-2(1H)-one and 2-hydroxybenzaldehyde and its metal complexes with Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Hg(II) ions have been synthesized. Furthermore, the structure, electronic properties, and chemical reactivity of Schiff base and its metal complexes have been examined via Elemental analysis, Mass, (H-1, C-13 and N-15) NMR, FT-IR, CV, ESR spectra, Thermal analysis, and theoretically using the density functional theory. Initially, the ligand behaved as a neutral tridentate (NOO) ligand and all complexes displayed octahedral geometry, except Hg(II), which showed tetrahedral geometry. The values of molar conductance in DMSO suggested the non-electrolytic nature for all complexes. The coordinated and crystalline water molecules have been investigated by (TG/DTG) studies. The kinetic and thermodynamic parameters were computed using Horowitz-Metzger and Coats-Redfern methods. Moreover, the data obtained from XRD, SEM, TEM, EDX and AFM images unequivocally asserted the nano-sized metal chelates. In molecular modelling the geometries of Schiff base and its nano-sized Cu(II), Co(II) and Zn(II) hybrids were fully optimized with respect to the energy generated due to using the DFT method from DMOL3 calculations. The anticancer activity of the parent Schiff base and its nano-sized metal hybrids were screened, in addition to the interaction of the complexes with calf thymus CT-DNA, which was investigated via the UV-visible absorption method. Additionally, the mode of CT-DNA binding to the HL ligand and its nano-sized hybrids has been explored. Therefore the DNA cleavage activity by the HL ligand and its nano-sized hybrids was performed allowing the measurement of the solid-state dc electrical conductivity of the HL ligand and its nano-sized Co(II), Cu(II) and Zn(II) hybrids over 303-423 K, which were then found to be of semiconducting nature. (C) 2020 Published by Elsevier B.V.