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41.
Nahid Shahabadi Soraya Moradi Fili Soheila Kashanian 《Journal of Coordination Chemistry》2018,71(2):329-341
A copper(II) complex containing the ceftobiprole drug and 1,10-phenanthroline (phen) has been synthesized and characterized by UV–vis, FT-IR and mass spectra, and elemental analysis. The binding interaction between [Cu(cef)(phen)Cl2] complex and human serum albumin (HSA) was investigated using absorption, fluorescence emission and circular dichroism spectroscopies, and molecular docking. Thermodynamic parameters (ΔH < 0 and ΔS < 0) indicated that the hydrogen bond and van der Waals interactions played main roles in the binding of complex [Cu(cef)(phen)Cl2] to HSA. The results of CD and UV–vis spectroscopy showed that the binding of [Cu(cef)(phen)Cl2] to HSA induces some conformational changes in HSA. Displacement experiments predicted that the binding of [Cu(cef)(phen)Cl2] complex to HSA is located within domain III, Sudlow’s site 2, and these observations were substantiated by molecular docking studies. 相似文献
42.
Nahid Nishat Shahnawaz Ahmad Bhat Abdul Kareem Swati Dhyani Abdulrahman Mohammad Azar Ullah Mirza 《Journal of inclusion phenomena and macrocyclic chemistry》2018,92(3-4):395-409
Macro-cyclic ligands from adipic acid, ethylenediamine with diethyloxalate and diethylmalonate and their respective metal complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) with macro cyclic ligands (LO) and (LM) L [N,N′-bis(2-aminoethyl)hexanediamide] were synthesized successfully. These metal complexes were characterized by Fourier transform infrared, ultraviolet visible spectrometry, proton nuclear magnetic resonance spectroscopy, and mass Spectrometry, CHNS and thermogravimetric analysis. The elemental analysis confirms the structures for Mn(II), Co(II) and Ni(II) complexes similar to octahedral geometry, Cu(II) complexes as a square planar geometry and Zn(II) complexes in the tetrahedral geometry. The molar conductivities of all the metal complexes were taken in 10?3 M DMSO, and values of all the metal complexes showed their electrolytic nature which indicates the presence of chloride ions. Thermal analysis supports as the metal complexes are thermally stable. The result of antimicrobial activity against various microorganisms confirms that the metal complexes are potent bactericides and fungicides than the ligand. Metal complexes of LO with Cu(II) and Zn(II) were found to be highly active against S. typhimurium than the complexes of LM. 相似文献
Graphical abstract
43.
We have developed a facile and efficient method for the synthesis of functionalized novel furylquinolines. A variety of quinoline–furan conjugates were obtained via the condensation of 2-chloroquinoline-3-carbaldehyde with acetylenecarboxylates and isocyanides in good to excellent yields. 相似文献
44.
Immobilization of nickel ions onto the magnetic nanocomposite based on cross‐linked melamine groups: Effective heterogeneous catalyst for N‐Arylation of Arylboronic acids
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Ali Pourjavadi Nahid Keshavarzi Firouz Matloubi Moghaddam Seyed Hassan Hosseini 《应用有机金属化学》2018,32(2)
A new magnetic heterogeneous catalyst was synthesized by immobilization of nickel ions onto a cross‐linked polymeric nanocomposite composed of cyanuric chloride, ethylenediamine and functionalized magnetic nanoparticles. The resulting nitrogen rich support was capable of adsorbing large amounts of nickel ions (1.20 mmol g?1). The synthesized catalyst was characterized using AAS, TEM, FT‐IR, EDX, TGA, SEM, BET and XRD techniques. The performance of the prepared catalyst was investigated in the C‐N coupling of arylamines with aryl boronic acids. The reaction was carried out under a mild condition and good to moderate to good yields of products was obtained using only 5.0 mol% of the catalyst. The catalyst was easily recovered and reused for at least 7 times without any significant loss of its activity. 相似文献
45.
46.
We completely determine when a ring consists entirely of weak idempotents, units and nilpotents. We prove that such ring is exactly isomorphic to one of the following: a Boolean ring; Z3 ⊕ Z3; Z3 ⊕ B where B is a Boolean ring; local ring with nil Jacobson radical; M2(Z2) or M2(Z3); or the ring of a Morita context with zero pairings where the underlying rings are Z2 or Z3. 相似文献
47.
Nishat Nahid Rahis-ud-din Haq Mohammad M. Siddiqi Khwaja S. 《Transition Metal Chemistry》2003,28(8):948-953
Two new macrocyclic ligands 1,4,7,9,12-pentaaza-10,11-dioxo-8,9,12,13-bis-(1-oxo-3-thio-2-hydropyrimidine)-trideca-7,13-diene, (L1) and 1,4,7,9,12-pentaaza-10,12-dioxo-8,9,13,14-bis-(1-oxo-3-thio-2-hydropyrimidine)-tetradeca-7,14-diene, (L2) and their complexes with CrIII, MnII, FeIII, CoII, NiII, CuII and ZnII have been synthesized, and characterized by elemental analysis, i.r., 1H-n.m.r., e.p.r., u.v.–vis. spectroscopy, magnetic susceptibility and conductance measurements. The conductivity measurements suggest that the complexes of divalent metal ions are 1:1 electrolytes whereas the trivalent metal ions are non-electrolytes. On the basis of electronic spectra and magnetic moment measurements the CrIII and FeIII complexes are octahedral, while the divalent metal complexes are tetrahedral except for the NiII and CuII complexes which are proposed to have square planar geometry. All the ligands and their complexes have been screened against gram-positive bacteria Staphylococcus aureus and gram-negative bacteria E. coli. The results show that they inhibit the growth of bacteria. 相似文献
48.
A sensitive and selective flow injection method for the determination of phosphatidylcholine (PC) in sediment pore waters and extracts is described. It involves the use of phospholipase C, alkaline phosphatase and choline oxidase co-immobilized on controlled pore glass in a packed column reactor. The final product of the enzymatic reaction of phosphatidylcholine is hydrogen peroxide, and this is detected by measuring the chemiluminescence emission resulting from cobalt(II) catalysed reaction with luminol. The flow injection method is rapid (30 injections/h), reproducible (1.4% R.S.D. at 3 μM PC, n = 10) with a detection limit of 0.14 μM (estimated from 3σn−1 of the measured blank). A linear calibration response was obtained over a concentration range of 0.5-9 μM (r = 0.999). The method has been applied to the determination of phosphatidylcholine in sediment extracts and sediment pore waters. 相似文献
49.
Alireza Ghassempour Nahid Mashkouri Najafi Ali Asghar Amiri 《Journal of Analytical and Applied Pyrolysis》2003,70(2):3103-261
Rapid and sensitive determination of citric acid in fermentation media by pyrolysis mass spectrometry (Py–MS) is proposed. Owing to high specificity of this method, distinguishing the citric acid from the matrix and by-products formed in the Krebs cycle is possible. Selected ion monitoring (SIM) mode is used for quantitative measurements, in which mass to charge (m/z) values of 175 of citric acid and 138 of 3-nitroaniline as internal standard are chosen. Limit of detection (LOD) for this method has been found to be 1 ng ml−1 and the linear working range was 10 ng ml−1–100 mg ml−1. Relative standard deviation (R.S.D.) of the method for five replicates was 0.84%. Results of Py–MS are compared with those obtained by UV–vis spectrophotometric method. Also, factor analysis is used for evaluating the influence of pH, molasses concentration, time and shaker intensity on the production of citric acid by Aspergillus niger. 相似文献
50.
Sartaj Tabassum Nahid Nishat Farukh Arjmand Lutfullah Khwaja Salahuddin Siddiqi 《Transition Metal Chemistry》1996,21(2):97-100
Summary Benzoylacetic acid (1 mol) interacts with ethylenediamine or with propanediamine (2 mol) to yield new N4 macrocycles 1,5,8,12-tetraazacyclotetradeca-2,4,9,11-tetraphenyl-3, 10-dicarboxylic-4,11-diacetic acid- 1,8-diene (L1) and 1,5,9,13-tetraazacyclohexadeca-2,4,10,12-tetraphenyl-3, 11-dicarboxylic-4,12-diacetic acid-1,9-diene (L2), respectively. These macrocycles have been successfully complexed with CrIII, FeIII, MnII, CoII, NiII, CuII and ZnII. The complexes of the divalent metal ions are non-electrolytes, while those of FeIII and CrIII are 1:1 electrolytes in DMSO. On the basis of ligand field spectra and magnetic moments an octahedral geometry has been proposed for all the complexes. 相似文献