Spectroscopic and theoretical studies on Cr (III), Mn (II) and Cu (II) complexes of hydrazone derived from picolinic hydrazide and O-vanillin and evaluation of biological potency

Trivalent Cr (III) and divalent of both Mn (II) and Cu (II) complexes containing hydrazone ligands derived from the condensation of picolinohydrazide with O-vanillin were synthesised and characterized by elemental analysis, spectral and magnetic measurements. The suggested octahedral structures were confirmed by applying DFT optimization and conformational studies. The thermal decomposition behaviour of Mn (II) complex is discussed. The evaluation of kinetic parameters (E_a, A, ∆H, ∆S and ∆G) of all thermal degradation stages have been evaluated using Coats-Redfern and Horowitz-Metzger approaches. The band gap results suggested that these complexes are semi-conductors and lie in same range of highly efficient photovoltaic materials. Antibacterial studies showed that higher activity of complexes than of ligands. Assay on the antioxidant activity (DPPH and SOD) of the above complexes revealed the high SOD-activity of Mn (II) complex and high DPPH-activity for ligand.     

Synthesis,analytical and spectral characterization for new VO (II)-triazole complexes; conformational study beside MOE docking simulation features

New triazole-derivatives were synthesized and characterized (spectral, analytical and conformational). After that, the new derivatives were coordinated with VO (II) atom to prepare new series of complexes. Distorted octahedral and square-pyramidal geometries, were the geometries suggested based on UV- Vis and ESR spectra. A neutral poly-dentate mode of bonding was proposed by 1:1 (M:L), for all complexes. TGA study supports the molecular formula of VO (II) complexes as well as, mass spectral-analysis that executed for examples. The isotropic, anisotropic, molecular orbital and Hamiltonian parameters were estimated upon ESR spectra, for selected complexes. XRD patterns were executed for three complexes, two among appeared with particulate-sizes in nanometer-range. Conformational study was executed for all synthesizes applying RTD-B3LYP-FC method. Essential physical parameters were estimated and discussed. MOE-docking that considered a bright part, was performed over all compounds towards 3s7s and 5jm5, as functional tumor proteins. The docking interaction parameters, introduced strongly some synthesizes to be anti-tumor agents.     

New catalytic approach for nano-sized V(IV), Cr(III), Mn(II) and Fe(III)-triazole complexes: detailed spectral,electrochemical and analytical studies

Research on Chemical Intermediates - A new series of metal ion complexes from a triazole-Schiff base was synthesized and fully characterized. The tridentate mode of coordination was the only mode...     

Copper–acetanilide complexes: synthesis,characterization, crystal structure,computational analysis and their application as heterogeneous catalysts for biodiesel synthesis from frying waste oils

Research on Chemical Intermediates - Novel copper complexes were prepared from acetanilide derivatives and deliberately characterized. The molar ratio obtained was 1:1 through neutral bi-dentate...     

Electro-synthesis approach for some metal ion complexes derived from thiosemicarbazide; characterization,conformational, inhibitory simulation and Hirshfeld surface properties

Series of Co (II), Cu (II), Zn (II) and Sn (II) complexes derived from thiosemicarbazide ligand (HTSC), was synthesized by environmentally favorable method (electrochemical). All isolated complexes, were deliberately characterized by available analytical and spectral tools. The proposed molar ratio was 1:2 (M:L) as the only isolated one, beside the significant contribution for solvent molecules. The octahedral configuration was proposed for all complexes. Conformational analysis was implemented using advanced program to determine the best structural forms for complexes. Moreover, essential parameters were calculated to export important features for studied complexes. Meanwhile, Hirshfeld crystal surface properties, were interested to illustrate strength of packing interaction forces. Furthermore, distinction of site types inside the molecule and their H-donor or H-acceptor ability. Antimicrobial study was conducted against different microorganisms, to assert on the importance of new complexes in therapeutic field. Furthermore and to strengthen the study, the inhibition simulation was performed with respect to all complexes against selected pathogen proteins. Essential interaction data, were exported for each docking process, to classify inhibition efficiency. Co (II) and Cu (II) complexes were the complexes that played well in therapeutic simulation treatments against Bacillus subtilis (1bn8) and Candida albicans kinase (4c0t) proteins.     

Elaborated spectral,modeling, QSAR,docking, thermal,antimicrobial and anticancer activity studies for new nanosized metal ion complexes derived from sulfamerazine azodye

New azodye ligand (H₂L) and its relative Cr(III)-, Mn(II)-, Fe(III)-, Co(II)-, Ni(II)-, Cu(II)-, Zn(II)- and Cd(II)-nanosized complexes were prepared. A new synthesized compounds were characterized using spectral (mass, IR, UV–Vis, XRD, and ESR) and analytical (elemental, molar conductance, thermal and magnetic moment measurements) tools. Infrared spectra showed that the ligand behaves as a monobasic bidentate, coordinating with central atoms through carbonyl oxygen and α-hydroxyl group. The geometrical structures of Cr(III) and Fe(III) complexes were found to be in octahedral configuration, whereas Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes have tetrahedral forms. XRD patterns reflect an amorphous appearance of all investigated complexes. TEM images showed nanosized particles and identical distribution over the complex surface. Molecular modeling for the drug ligand and its metal ion complexes were performed using Gaussian09 program to assert on their structural formulae. Some essential parameters were extracted using HOMO and LUMO energies. AutoDock tools 4.2 was used to simulate the interaction process with infected cell proteins to expect the experimental pathway. The inhibition activity of drug ligand and its metal ion complexes was evaluated towards different types of bacteria and fungi through in vitro antimicrobial activities. The antitumor activities of all compounds are straightened towards human liver carcinoma (HEPG2) cell lines. Fe(III) and Co(II) complexes exhibited IC₅₀ of 2.90 and 4.23 µg mL^?1, respectively, which means they are more potent anticancer drug than the standard (doxorubicin, IC₅₀ = 4.73 µg mL^?1). Therefore, the two complexes may consider promising anticancer drugs.

     

Synthesis and structural characterization of oxovanadium(IV) complexes of dimedone derivatives

We have successfully synthesized new oxovanadium (IV) complexes with dimedone derivatives and their structure were confirmed by elemental analyses, spectroscopic techniques (FT-IR, UV–visible, EPR) and thermal analysis. The reaction of [VO (acac)₂] with the azo dimedone ligands ( HL _n ) produced mononuclear oxovanadium (IV) complexes with formula [VO (L_n)₂]H₂O. Results of the molar conductance proved that VO²⁺ complexes are non-electrolytes and fall in the range 14–16 Ω-¹cm²mol⁻¹. The coordination geometry of VO (IV) complexes is square-pyramidal, where vanadium (IV) ion is coordinated by oxygen atom of the carbonyl (C=O) group, and nitrogen atom of the deprotonating hydrazone moiety (–NH–), while the fifth position is occupied by an oxo group. Moreover, the optimized structure, bond angles, bond lengths, as well as the calculated quantum chemical parameters of the complexes have been estimated. DNA binding activities of the complexes were investigated using electronic absorption titration and viscosity measurements. The obtained results showed groove binding of the complexes to CT-DNA accompanied with a partial insertion of the ligand between the base stacks of the DNA with a binding constant of 2.07–5.51 x 10⁵ M⁻¹ range. Evaluation results of the synthesized complexes against the human cancer cell lines HepG-2 and MCF-7, as compared to the positive controls in the viability assay of vinblastine and colchicine have been reported. The in vitro anti-oxidant activity of all the complexes is determined by DPPH free radical-scavenging assay. Finally, the anti-microbial activities of the complexes have been investigated against fungal (Candida albicans), gram negative bacteria (Escherichia coli), and gram positive bacteria (Staphylococcus aureus) using the disc-diffusion method.     

Characterization of new Co(II) complexes and photographic monitoring for their toxic impact on breast cancer cells according to simulation study

Five new nitrogen-rich ligands (thioanhydrides) were synthesized and fully characterized. Then, their corresponding Co(II) complexes were prepared and also elucidated by analytical and spectral conformational techniques. First of all, the mono-negative tri-dentate mode was proposed with all derivatives towards mono-nuclear central atom. According to ligand field transitions and magnetic susceptibility values, the square-planar as well as octahedral geometries were the forms suggested. The presence of water molecules was investigated thermally. For conformational implementation under optimal conditions, energy minimization was carried out and fundamental data were obtained and studied. In silico investigation was carried out using the MOE docking approach to predict the inhibition activity for the new compounds. The Co(II)– 3e complex played an excellent inhibitory role. After that and based on preliminary results, in vitro antitumor screening against MCF-7 cell line was conducted for all Co(II) complexes. The results were consistent with that for standard drug (doxorubicin), and the inhibition feature for the complexes was ranked. Through photographic monitoring, outstanding inhibition activity towards breast cancer spreading was recorded for the Co(II)– 3e complex, which coincides well with MOE docking data.     

Green synthesis approach for Fe (III), Cu (II), Zn (II) and Ni (II)-Schiff base complexes,spectral, conformational,MOE-docking and biological studies

Green synthesis of Fe (III), Cu (II), Zn (II) and Ni (II)-Schiff's-base complexes from 2-oxo-N-(pyridine-2-yl)-2-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)acetamide(H₂L)ligand. All new complexes were characterized via several spectroscopic and analytical techniques, to establish their molecular and structural formulae. All complexes appeared have 1:1 molar ratio (M:L). The ligand contributed as a neutral poly-dentate towards the metal ions. Moreover, material-studio program was used to predict the most fitted atomic-skeletons for investigated compounds by applying DFT method. MOE docking module (vs. 2015) was used to examine the degree of inhibition for new compounds versus three infected-cell proteins (1bqb, 2gt1 and 4esw). Also, antimicrobial and colorimetric assess for compounds that bind DNA were performed     

Structural,conformational and therapeutic studies on new thiazole complexes: drug-likeness and MOE-simulation assessments

Research on Chemical Intermediates - A series of new complexes derived from Pd(II), Cu(II) and Fe(III) ions reacted with thiazole derivative (HL, CPTP) was prepared. Structures of all new compounds...