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[Display omitted] • Pd2+ and VO2+-complexes of succinyldihydrazone derivative are synthesized and characterized. • VO-catalyst exhibits higher catalytic potential than that of Pd-catalyst in the oxidation of sulfides. • The antimicrobial and anticancer potential of M−complexes and their ligand are examined. • Their binding to ct DNA is examined via UV–Visible spectroscopy and hydrodynamic measurements. According to the significant role of transition metals in their metallo-organic frameworks catalytically and biologically, two new dinuclear homoleptic complexes of Pd2+ and VO2+ ions (PdLC 2 and VOLC 2 , respectively) with succinyl dihydrazone diisatin ligand (H 2 LC 2) were constructed. The effect of the M2+ ion type was distinguished in the productive redox protocol of diphenyl sulfide (DiPhS) and methylphenyl sulfide (MePhS) within H 2 O 2. Considerable productivity was assigned by the yielding percentages of diphenyl sulfoxide (DiPhSO) and methylphenyl sulfoxide (MePhSO) (the mono-oxo-selective product) catalyzed by PdLC 2 or VOLC 2 , in which VOLC 2 catalyst exhibited little more classified efficiency than that of PdLC 2 , referring to the progressed redox potential of V4+ ion in VOLC 2 catalyst. Their biological performance was recorded based on their inhibited potential against the growing power of some cancer/normal cells of humans, bacteria, as well as, fungi. The bio-studies appointed the role and job of M2+ ion (Pd2+ or VO2+ ion) in its chelated MLC 2 complex over the free ligand, H 2 LC 2. Moreover, their interacted modes with ct DNA (i.e. calf thymus DNA) were examined via the viscometries and spectrophotometric titration. Since the two chelates (PdLC 2 and VOLC 2) represented an attractive performance for the inhibited action for the current microorganisms and the cancer cell lines of humans' growth over the free H 2 LC 2 ligand. PdLC 2 and VOLC 2 complexes displayed an appreciable reaction with ct DNA more than that of their free organo-ligand H 2 LC 2. From the binding constant (K b) and Gibb's free energy (Δ G b ≠) values, both PdLC 2 and VOLC 2 exhibited more binding interaction within ct DNA than that of the H 2 LC 2 ligand, with the progressed Lewis acidity, electronegativity, and lipophilic feature (hydrophobicity). [ABSTRACT FROM AUTHOR]

[Display omitted] • O = V4+ and O = Zr4+-complexes of malonyldihydrazone derivative are synthesized and characterized. • The antimicrobial (bacteria and fungi) and anticancer potential of MO-complexes and their ligand are examined. • Their binding to ct DNA is examined via UV–Visible spectroscopy and hydrodynamic measurements. • O = V4+ and O = Zr4+-complexes more biological reactivity over their free ligand based on Tweedy's chelation theory. • Their catalytic reactivity was examined in the thiophene oxidation with H 2 O 2 , in which they assigned high catalytic performance. Bis -tridentate diisatin malonyldihydrazone ligand, H 2 Lhm, was prepared from the condensed reaction of isatin with malonic dihydrazide. Its ligandated coordination features were explored from its reactivity towards VO2+ and ZrO2+ ions forming two novel complexes of dinuclear homoleptic design (VOLhm and ZrOLhm, respectively). Elucidation of their chemical structures was formulated within various available spectroscopic ways, besides EA (the elemental analyses), conductivity measurements, and magnetic characteristics. Their bio-accomplishment was evaluated depending on their inhibited action against the growing ability of some well-known bacteria, fungi, and cancer/normal cells of human. The biological results appointed the employed role of VO2+ or ZrO2+ ion in its chelated complex over the free ligand, H 2 Lhm. Their binding mode with ct DNA (i.e. calf thymus DNA) was examined within the viscometric and spectrophotometric titration. VOLhm and ZrOLhm represented a fascinating role in the inhibition of the current microorganisms and the human cancer-normal strains' growth over H 2 Lhm. VOLhm and ZrOLhm exhibited a notable interaction with ct DNA more than that of their H 2 Lhm ligand. From the values of binding constant (K b = 16.36 and 14.49 × 107 mol−1 dm3) and Gibb's free energy (Δ G b ≠ = −47.21 and −44.16 kJ mol−1), VOLhm displayed more bio-action within ct DNA than ZrOLhm and H 2 Lhm, referring to the role of VO2+ ion with high redox potential enhancing the bio-reactivity of VOLhm. The catalytic behavior of VOLhm and ZrOLhm was given within the oxidation of thiophene (as a desulfurization process), homogeneously using H 2 O 2. The oxidation optimization was enhanced depending on the type of O = M4+ ion in its complex catalyst (through 4 h at 30 °C with 60% yielding of monooxo-product using VOLhm and 4 h and 40 °C with 53% using ZrOLhm). [ABSTRACT FROM AUTHOR]

Structural features and catalytic activities of five ternary copper (II)-Schiff base complexes are investigated. The ligands are derived from 3-methoxysalicylaldehyde (MS) or 4-diethylaminosalicylaldehyde (DS) and amino acids {L-phenylalanine (Phe), L histidine (His) or DL-tryptophan (Trp)}, as primary ligands, and 2,4′-bipyridyl (DP) as a secondary ligand. Cu(II)-complexes are characterized by various physicochemical tools. The catalytic efficiency of Cu(II)-complexes is studied in the oxidation of benzyl alcohol by an aqueous H2O2 in different reaction conditions. Temperature and catalyst features are involved in order to obtain the optimized catalytic oxidation conditions of benzaldehyde production. The Schiff base ligands and their ternary complexes are screened for their antimicrobial activities in various types of fungi and bacteria. The interaction between Cu(II)-complexes and (CT-DNA) was examined by employing various techniques, including viscosity, spectral and gel electrophoreses studies. [ABSTRACT FROM AUTHOR]

Two binary and two ternary mono-oxovanadium (IV) complexes of acetylacetonate, curcumin and N, N′-bis(2-pyridyl)thiourea were synthesized. They were characterized using elemental analysis, infrared and UV-visible spectroscopies and magnetic and conductivity measurements. The formation constants Kf were determined from spectrophotometric measurements. The catalytic potential of the VO complexes was investigated for the oxidation of 1-octene by aqueous H2O2 in acetonitrile. They display high catalytic potential for the conversion of 1-octene with low chemoselectivity to the epoxy product. The VO complexes exhibit good antibacterial and antimicrobial activities. The antioxidant activity of the VO complexes and their ligands was investigated. The VO complexes show high DNA affinity and DNA cleavage ability. [ABSTRACT FROM AUTHOR]

• Cu(II) and Fe(II) complexes of isatin hydrazone derivative are synthesized and characterized. • Cu-catalyst exhibits little more catalytic potential over that of Fe-catalyst in benzyl alcohol oxidation. • The antimicrobial and anticancer potential of both complexes are examined against some bacterial, fungal and human cancer cells. • Their binding ability to ctDNA is examined via UV–Visible spectroscopy and hydrodynamic measurements. Divalent para-magnetic copper(II) and iron(II) chelates of Schiff base isatin hydrazone derivative are synthesized and characterized, as CuLONOCl and Fe(LONO) 2 , respectively. With different stoichiometric ratios (molar ratios) of 1: 1 and 1: 2 of Cu2+ or Fe2+ ion to the ligand (HLONO), both chelates are prepared with distorted square planar and octahedral structures, respectively. The catalytic action of both CuLONOCl and Fe(LONO) 2 is examined in the homogeneous oxidation benzyl alcohol using H 2 O 2 to benzaldehyde (the selective product). All studied compounds involved in the antimicrobial and anticancer studies and also against the ct DNA. Catalytically, their optimization is progressed within the influence of temperature, time and solvent. CuLONOCl manifests an optimized catalytic atmosphere for the yield percentage of benzaldehyde (92%) at 70°C after 4 h, whereas, Fe(LONO) 2 displays less catalytic action with less yield (88%) after 3 h at 90°C. The variation in their structure and central metal ion assign to understand the difference in their catalytic potentials. The proposed mechanism for the oxygenation process based on electron-oxygen transfer steps. In the biological studies, CuLONOCl displays more action against some common microbes (bacteria and fungi) and cancers growth compared to that of Fe(LONO) 2. The role of M2+ ion in its complex and its geometries illustrate their utility in such biological studies within Tweedy's chelation theory. Their interaction with ct DNA (calf thymus DNA) is aimed to represent the impact of Cu2+ and Fe2+ ions in the complexing agents with the influence of their structures through the changes and shifts of spectroscopic the viscosity investigations. Their interaction with ct DNA is illustrated spectroscopically according to the derived values of the binding constants, K b , and the negative Gibbs' free energy, Δ G b ≠. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The catalytic oxidation of an anionic reactive blue 19 (RB19) dye solution using a novel synthesized γ-MnO2/MWCNT nanocomposite catalyst with H2O2 was investigated. Three different molar concentrations of MnO2 loaded over modified MWCNT with nitric acid were prepared. The impact of initial molar concentrations of H2O2 (0.076–0.333M), catalyst loading (0–0.05g), initial pH of solution (2–10), and initial dye concentration (50–500mg/l) on the decolorization process was studied. Morphology, crystallinity and textural characteristics of the modified MWCNT before and after deposition of MnO2 were examined by SEM, XRD, EDX, FTIR and N2 adsorption at 77K, respectively. It was found that the core–shell nanostructure was formed by the uniform incorporation of birnessite-type (γ-MnO2) nanoflakes growth around the surface of the activated MWCNT. The present study highlighted that the prepared 0.5MnO2/MWCNT nanocomposite catalyst and 0.333M H2O2 exhibited a higher catalytic oxidation of a RB19 dye than other catalysts at a slightly acidic pH. Recycling studies with 0.5MnO2/MWCNT nanocomposite catalyst with 0.333M H2O2 showed that it can be reused within three runs in oxidation experiments. Finally, the prepared nanocomposite catalyst with 0.5MnO2 has the amenability to operate efficiently in the decolorization of dyes from wastewater. [Copyright &y& Elsevier]

• VO2+, ZrO2+ and Zn2+-complexes were synthesized from the asymmetrical tetradentate imine ligand. • The catalytic differentiation between VO2+-complex and the new ZrO2+- and Zn2+-complexes was studied in the 1,2-cyclohexene (ep)oxidation. • Various parameters were investigated (temperature, time, solvent, oxidant type and catalyst amount), with theoretical evaluation of the mechanism. • Some cyclic and acyclic alkenes were studied in (ep)oxidation reactions. • The catalytic reactivity VO-, ZrO- and Zn-complexes was tested in the 2-aminothiophene oxidation by H 2 O 2 with detection of the most chemoselectives. Three mononuclear di-valent VO2+, ZrO2+ and Zn2+-complexes (VOL, ZrOL and ZnL, respectively) were prepared from asymmetrical di-basic tetradentate di-imine ligand (6,6′-((1 E ,1′ E)-((4-chloro-1,2-phenylene)bis(azaneylylidene))bis(methaneylylidene))bis(2-ethoxy phenol, H 2 L). To confirm the M-complexes compositions, various spectral tools (FT-IR, EI/M and UV-Vis. spectra), molar conductance, thermal, elemental analysis and pXRD analyses were accomplished. Distorted octahedral geometry was confirmed for ZnL and square pyramidal geometry was elucidated for VOL and ZrOL. Their catalytic efficiency was investigated in the epoxidation of 1,2-cyclohexene by H 2 O 2. They exhibited moderate to excellent catalytic control. The effect of temperature, time, solvent, type of oxidant and amount of catalysts were studied in order to determine the optimal catalytic atmosphere. The catalysts screening for epoxidation of alternative cyclic and acyclic olefins at optimization was reported. The variation of central metal ions from high to low valents (Zr4+, V4+and Zn2+ ions) and their capability for oxidation control their catalytic potential are the most effective aspects in the epoxidation reaction. The catalytic oxidation of 2-aminothiophene within VOL, ZrOL and ZnL, as a first trial, by H 2 O 2 was examined. Also, QSAR parameters and DFT studies were performed to predict the catalytic properties of VOL, ZrOL and ZnL, to assert on chosen application. Effective surface properties of VO(II) complex were promoted for progressing its catalytic activity, which already happened. The catalytic mechanism was supported by the sequenced stability difference between proposed intermediates based on the difference in their recorded formation energy from the DFT study. [Display omitted] [ABSTRACT FROM AUTHOR]