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11.
Urea‐based ionic liquid stabilized on silica‐coated Fe3O4 magnetic nanoparticles, {Fe3O4@SiO2@(CH2)3‐Urea‐SO3H/HCl}, as an unexceptionable and smooth releasing urea fertilizer in alkali soils was synthesized and fully characterized using Fourier transform infrared, UV–visible and energy‐dispersive X‐ray spectroscopies, X‐ray diffraction, scanning and transmission electron microscopies, atomic force microscopy and thermogravimetric analysis. The nanostructure catalyst as a novel, green and efficient catalyst was applied for the synthesis of bis(indolyl)methane derivatives via the condensation reaction between 2‐methylindole and aldehydes at room temperature under solvent‐free conditions. Also, pyrano[2,3‐d]pyrimidinone derivatives were prepared in the presence of the nanomagnetic urea‐based catalyst by the one‐pot three‐component condensation reaction of 1,3‐dimethylbarbituric acid, aldehydes and malononitrile under solvent‐free conditions at 60 °C. To the best of our knowledge, this is the first report of the synthesis of urea‐based ionic liquid stabilized on silica‐coated Fe3O4 magnetic nanoparticles. So the present work can open up a new and promising insight in the course of rational design, synthesis and applications of task‐specific fertilizer‐based nanomagnetic ionic liquids with desirable properties as unexceptionable substances for sustainable processes. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
12.
In current study, antitumor activity of two series of the newly synthesized spiropyrroloquinoline isoindolinone and spiropyrroloquinoline aza-isoindolinone scaffolds was evaluated against three human breast normal and cancer cell lines (MCF-10A, MCF-7 and SK-BR-3) and compared with cytotoxicity values of doxorubicin and colchicine as the standard drugs. It was found that several compounds were endowed with cytotoxicity in the low micromolar range. Among these two series, compounds 6i, 6j, 6k and 7l, 7m, 7n, 7o containing 3-ethyl-1H-indole moiety were found to be highly effective against both cancer cell lines ranging from \(0.080 \pm 0.001\) to \(11.91 \pm 1.39\,\upmu \hbox {M}\) in comparison with the corresponding analogs. Compared with human cancer cells, the most potent compounds did not show high cytotoxicity against human breast normal MCF-10A cells. Generally, most of the evaluated compounds 6a–l and 7a–o series showed more antitumor activity against SK-BR-3 than MCF-7 cells. Moreover, comparative molecular field analysis (CoMFA) as a popular tools of three-dimensional quantitative structure–activity relationship (3D-QSAR) studies was carried out on 27 spiropyrroloquinolineisoindolinone and spiropyrroloquinolineaza-isoindolinone derivatives with antitumor activity against on SK-BR-3 cells. The obtained CoMFA models showed statistically excellent performance, which also possessed good predictive ability for an external test set. The results confirm the important effect of molecular steric and electrostatic interactions of these compounds on in vitro cytotoxicity against SK-BR-3.  相似文献   
13.
Research on Chemical Intermediates - In this investigation, a new application of 1H-imidazol-3-ium tricyanomethanide catalyst was explored. The catalyst presented a robust catalytic applicability...  相似文献   
14.
Hydrogen bond assisted proton transfer reactions were investigated in 3-methyl-1H-imidazole-2(3H)-selone (MSeI) and 1H-imidazole-2(3H)-selone (SeI) at B3LYP/6-311++G(2d,2p) level of theory. The B3LYP results predict that the direct proton transfer process in MSeI and SeI is more difficult than the water-assisted one. The results also show that the selone complexes are more stable than corresponding selenol ones. Interaction energies for a single NHSe hydrogen bond in dimers MSeI and SeI are −31.3 and −32.7 kJ/mol, respectively. ZPE-corrected binding energies in the self-association complexes of the MSeI and SeI are greater than the water-associated complexes. The small negative value of H(r) obtained by AIM analysis at B3LYP/6-311++G(2d,2p) level reveals some contribution of sharing interaction (partially covalent) to the SeHN bond in dimers of the MSeI and SeI. AIM data also reveal the partially covalent nature of SeH6 interaction and electrostatic nature of OH5 interaction in water-associated complexes. Results of charge analysis show that the selenium analogue of the methimazole is more nucleophilic than the methimazole. Our results confirm that the selenium analogue of methimazole can exist as a zwitterionic form.  相似文献   
15.
The present investigation describes synthesis of a good range of henna‐based compounds in the presence of novel nano cobalt phthalocyanine like molten salt (tetra‐2,3‐pyridiniumporphyrazinato cobalt tribromomethanide) [Co (TPPABr)]CBr3 as an efficient, recyclable and thermally stable heterogeneous catalyst.  相似文献   
16.
1,4-Dinitropyrazine-1,4-diium trinitromethanide {[1,4-pyrazine-NO2][C(NO2)3]2} as a novel nanostructured molten salt (NMS) catalyzed the synthesis of 2-amino-3,5-dicarbonitrile-6-sulfanylpyridine derivatives via the one-pot three-component condensation reaction between several aromatic aldehyde, malononitrile and benzyl mercaptan at room temperature under solvent-free conditions. The synthesized NMS catalyst was fully characterized by FTIR, 1H NMR, 13CNMR, mass, thermal gravimetric, X-ray diffraction patterns, scanning electron microscopy and transmission electron microscopy analysis. The major advantages of described methodology are mildness, ease of separation, good yields and short reaction times. A rational mechanism was suggested for the final step of the 2-amino-3,5-dicarbonitrile-6-sulfanylpyridines synthesis. We think that the proposed mechanism has potential for entering into the graduate text book in the future.  相似文献   
17.
Binding properties of myelin basic protein (MBP) from bovine central nervous system due to the interaction by divalent magnesium ion (Mg2+) was investigated at 27°C in aqueous solution using isothermal titration calorimetry (ITC) technique. An extended solvation model was used to reproduce the enthalpies of Mg2+-MBP interaction over the whole Mg2+ concentrations. It was found that there is a set of two identical and noninteracting binding sites for Mg2+ ions. The dissociation equilibrium constant is K d=45.5 μM. The molar enthalpy of binding site is identical for both sites; ΔH=−15.24 kJ mol−1. The solvation parameters recovered from the solvation model were attributed to the structural change of MBP due to the metal ion interaction.  相似文献   
18.
Molecular Diversity - Three-component reaction of aldehydes with 3-(1H-indol-3-yl)-3-oxopropanenitrile and 1H-1,2,4-triazol-5-amine under the solvent-free condition at 70 °C was...  相似文献   
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