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71.
Ilknur Babahan Ali Özmen Mehran Aksel Mehmet Dincer Bilgin Rukiye Gumusada Muhammet Emin Gunay Fatih Eyduran 《应用有机金属化学》2020,34(7):e5632
In this study, a novel bidentate ligand containing oxime, hydrazone, and indole moieties and its BF2+-bridged transition metal complexes [Ni(II), Cu(II), and Co(II)] were synthesized and their cytotoxic activities against prostate and breast cancer cells were investigated. The vic-dioxime ligand bearing indole–hydrazone side groups was synthesized by reacting antiglyoximehydrazine (GH2) with 3-methoxy indole. The ligand forms mononuclear complexes with a metal-to-ligand ratio of 1:2 with M = Co(II)(H2O)2, Ni(II), and Cu(II). These metal complexes were then reacted with BF3(C2H5)2O to obtain BF2+-bridged transition metal complexes. The Co(II) complex of the ligand is proposed to be octahedral with water molecules as axial ligands, whereas the Ni(II) and Cu(II) complexes are proposed to be square planar. Spectral studies showed that the ligand bonded to the metal ion in a neutral bidentate fashion through the azomethine nitrogen atom and the imine oxime group. Structural assignments are supported by a combination of 1H nuclear magnetic resonance (NMR), 13C NMR, Fourier-transform infrared, LC/MS, elemental analyses, and magnetic susceptibility testing. For determining the cytotoxic effects of the novel anticancer products, cancer cells were cultured. The antiproliferative effects were determined using the MCF-7 breast cancer and PC-3 prostate cancer cell lines. The antiproliferative effects of the products were analyzed and their apoptotic or necrotic effects were determined with the Hoechst/propidium iodide double staining method in both cancer cell lines. Paclitaxel was used as the positive control (1 μm ). The results indicated that the newly synthesized compounds are effective on both cell lines between concentrations of 5 and 40 μm and show their effects by apoptotic mechanisms. Besides, these products were found to be more effective on the MCF-7 cell line. The cytotoxic efficiency of the newly synthesized products was more than that of paclitaxel (depending on concentration), which is a chemotherapeutic agent used in cancer therapy. 相似文献
72.
A phosphovanadomolybdate hybridized with an anchored dicationic ionic liquid on Al‐MCM‐41 was prepared through the anion exchange and characterized by 1H and 13C NMR, FTIR, UV–Vis, XRD, XPS, TGA, TEM, FESEM, ICP‐OES and BET techniques. The obtained data demonstrated that the composite is a porous material with the high surface area and also having a large pore volume which are 405 m2 g?1 and 0.616 cm3 g?1 respectively. The prepared composite has shown an acceptable catalytic activity for converting benzene selectively to phenol with hydrogen peroxide as eco‐friendly oxidant. Under the optimized reaction conditions, the hybrid catalyst resulted in phenol yield of 14.8% with 100% selectivity and a TOF value of 20.0 h?1. The catalyst also revealed a desired recovery and reusability. The efficient performance of the composite is related to the textural and polyoxometalate properties. 相似文献
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Omid Sadeghi Mehran Amiri Dr. Eric W. Reinheimer Prof. Dr. May Nyman 《Angewandte Chemie (International ed. in English)》2018,57(21):6247-6250
Metal oxo clusters and metal oxides assemble and precipitate from water in processes that depend on pH, temperature, and concentration. Other parameters that influence the structure, composition, and nuclearity of “molecular” and bulk metal oxides are poorly understood, and have thus not been exploited. Herein, we show that Bi3+ drives the formation of aqueous Fe3+ clusters, usurping the role of pH. We isolated and structurally characterized a Bi/Fe cluster, Fe3BiO2(CCl3COO)8(THF)(H2O)2, and demonstrated its conversion into an iron Keggin ion capped by six Bi3+ irons ( Bi6Fe13 ). The reaction pathway was documented by X‐ray scattering and mass spectrometry. Opposing the expected trend, increased cluster nuclearity required a pH decrease instead of a pH increase. We attribute this anomalous behavior of Bi/Fe(aq) solutions to Bi3+, which drives hydrolysis and condensation. Likewise, Bi3+ stabilizes metal oxo clusters and metal oxides in strongly acidic conditions, which is important in applications such as water oxidation for energy storage. 相似文献
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78.
Honari Mehran Sanaeishoar Haleh Kiasat Ali Reza Mohammadi Mohammad Kazem 《Research on Chemical Intermediates》2021,47(5):1829-1841
A simple and efficient method for the synthesis of pyrazolopyranopyrimidines under solvent-free has been developed. The one-pot multicomponent condensation of arylaldehydes with hydrazine hydrate, ethyl acetoacetate and barbituric acid in the vicinity of a mesoporous basic nanomagnetic catalyst, namely DBU immobilized on Fe3O4@nSiO2@mSiO2 was synthesized in remarkably high yields and in short reaction times. Significantly, this catalyst can be easily separated from the reaction media by applying an external magnet, and can be reused for several cycles.
Graphical abstract79.
Measurement of drainage relative permeability by the centrifuge method was first introduced by Hagoort (SPE J. 29(3):139–150,
1980). It has been shown that capillary end effects can cause error in the measurement of relative permeability if a minimum
rotational speed is not honoured. To determine the minimum rotational speed that makes the capillary end effect negligible,
ω
min, we propose that the value of capillary-gravity number, N
cg, should be of the order of 10−2 or smaller. This conclusion is based on the use a Forward–backward scheme consisting of a forward numerical simulator developed
for centrifuge experiments and applying Hagoort’s method as a backward model. The article presents the use of this Forward–backward
scheme as a powerful tool for error analysis such as determining the impact of capillary end effects. By using this loop,
we first determine ω
min for specific core and fluid properties. Later, we generalize the ω
min calculations by using the definition of N
cg as a “rule of thumb” for designing relative permeability experiments by centrifuge method. We also demonstrate another use
of this loop for controlling the quality of the experimental data. 相似文献
80.
Omid Zabihi Mehran Aghaie Karim Zare 《Journal of Thermal Analysis and Calorimetry》2013,111(1):703-710
The thermo-physical properties of diglycidyl ether of bisphenol A (DGEBA)/isophoronediamine (IPDA) with iron nanoparticles were investigated using DSC, DMT, and TG analysis. Because of the higher values of the glass transition, it is recognized that the optimum behavior of the three-component system corresponds to the 10% loading level of iron nanoparticles. The addition of iron nanoparticles into the epoxy matrix resulted in a significant increment in the storage modulus and crosslink density. Also, the DGEBA/IPDA/10% iron nanoparticles showed an enhanced thermal stability owing to the introduction of iron nanoparticles as reinforcing filler. Curing reaction of DGEBA/IPDA with 10% iron nanoparticles was investigated by DSC at dynamic mode. Activation energy was calculated based on Kissinger method (66.52 kJ mol?1). Also, the advanced isoconversional method is utilized to describe the curing reaction process. In the dynamic DSC analyses, the curing kinetics could be successfully described with the two-parameter autocatalytic model (Sěsták–Berggren equation) and the overall reaction order was about 2.78. 相似文献