Synthesis, characterization, and anticancer activity of new binuclear complexes of 2,2′‐malonylbis(N‐phenylhydrazine‐1‐carbothioamide)

Abstract

The bimetallic complexes of 2,2′‐malonylbis(N‐phenylhydrazine‐1‐carbothioamide) have been prepared and characterized by elemental and spectral analyses. The free ligand exists in keto‐thione form, whereas in complexes it chelated to the metal ion in binegative tetradentate and neutral tetradentate manners. The electronic spectra and magnetic moment measurements showed that all the complexes have an octahedral geometry except the [Cu2(H2L)(OAc)2]EtOH complex which has square planar structure supported by the electron spin resonance (ESR) spectral data. In addition, thermal gravimetric analysis (TGA) carried out to clarify thermal stability of the ligand and its complexes. The optical band gap (Eg) was calculated using Tauc's equation and compared with their HOMO‐LUMO gap obtained from DFT quantum chemical calculations. Furthermore, the in vitro cytotoxic activity against Hela (Epitheliod Carcinoma) and WISH (Human amnion) cell lines of isolated compounds were examined. The data indicated that the ligand has very strong activity against Hela cell line and moderate activity against WISH cell line. Accordingly, the metal complexes showed more potent effect against Hela than WISH cell lines.

N′-(Furan-2-ylmethylene)-2-hydroxybenzohydrazide and its metal complexes: synthesis, spectroscopic investigations, DFT calculations and cytotoxicity profiling

“…On the other hand, the spectrum of Zn(II) complex, in DMSO - d 6 , showed a singlet signal at 13.98 ppm that was designated to the free phenolic proton (OH) [ 29 , 30 ]. The other singlet signal at 8.59 ppm was ascribed to the azomethine proton (HC=N) [ 42 , 50 ]. The appearance of only one signal due to the phenolic OH proton confirmed that it is free, no H-bond or metal binding, and the downfield shift of azomethine proton supported the participation of these groups in bonding to metal ion [ 42 , 50 ].…”

“…The other singlet signal at 8.59 ppm was ascribed to the azomethine proton (HC=N) [ 42 , 50 ]. The appearance of only one signal due to the phenolic OH proton confirmed that it is free, no H-bond or metal binding, and the downfield shift of azomethine proton supported the participation of these groups in bonding to metal ion [ 42 , 50 ]. The spectrum displayed the other bands at more or less the positions (Table 3 ).…”

Divalent transition metal complexes of multidentate nitrogen, oxygen and sulfur containing ligand: Design, spectroscopic, theoretical molecular modeling and antioxidant like activity

“…DFT method is one that conveys the chemical reactivity as well as the site selectivity of molecular systems. The energies of the frontier molecular orbitals (EHOMO, ELUMO) (figs.9-12 C & D), the energy band gap which explains the eventual charge transfer interaction within the molecule, electronegativity (v), chemical potential (l), global hardness (g), global softness (S) and global electrophilicity index (x) [39] are evaluated according to literature [40] and the data recorded in Table 6. This new reactivity index measures the stabilization in energy when the system acquires an additional electronic charge from the environment.…”