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81.
Moamen S. Refat Ahmed Gaber Yusuf S. Althobaiti Hussain Alyami Walaa F. Alsanie Sonam Shakya Abdel Majid A. Adam Mohamed I. Kobeasy Kareem A. Asla 《Molecules (Basel, Switzerland)》2022,27(13)
New Cu(II), Ni(II), Co(II), and Mn(II) complexes of the gabapentin (Gpn) bidentate drug ligand were synthesized and studied using elemental analyses, melting temperatures, molar conductivity, UV–Vis, magnetic measurements, FTIR, and surface morphology (scanning (SEM) and transmission (TEM) electron microscopes).The gabapentin ligand was shown to form monobasic metal:ligand (1:1) stoichiometry complexes with the metal ions Cu(II), Ni(II), Co(II), and Mn(II). Molar conductance measurements in dimethyl-sulfoxide solvent with a concentration of 10−3 M correlated to a non-electrolytic character for all of the produced complexes. A deformed octahedral environment was proposed for all metal complexes. Through the nitrogen atom of the –NH2 group and the oxygen atom of the carboxylate group, the Gpn drug chelated as a bidentate ligand toward the Mn2+, Co2+, Ni2+, and Cu2+ metal ions. This coordination behavior was validated by spectroscopic, magnetic, and electronic spectra using the formulas of the [M(Gpn)(H2O)3(Cl)]·nH2O complexes (where n = 2–6).Transmission electron microscopy was used to examine the nanostructure of the produced gabapentin complexes. Molecular docking was utilized to investigate the comparative interaction between the Gpn drug and its four metal [Cu(II), Ni(II), Co(II), and Mn(II)] complexes as ligands using serotonin (6BQH) and dopamine (6CM4) receptors. AutoDock Vina results were further refined through molecular dynamics simulation, and molecular processes for receptor–ligand interactions were also studied. The B3LYP level of theory and LanL2DZ basis set was used for DFT (density functional theory) studies. The optimized geometries, along with the MEP map and HOMO → LUMO of the metal complexes, were studied. 相似文献
82.
Sohail Khan Aftab Hussain Ansar Mehmood Shagufta Perveen Muhammad Imran 《Natural product research》2016,30(23):2629-2636
β-Sitosterol-3-O-(6?-O-13?-octadecenoyl)-β-D-glucoside (1), a new acyl β-sitosteryl glucoside, along with three known compounds β-sitosterol-3-O-β-D-glucoside (2), β-sitosterol (3) and methyl gallate (4) have been isolated from the ethyl acetate soluble fraction of methanolic extract of Ailanthus altissima fruits. Their structures were elucidated through spectroscopic data including 2D NMR, ESI-MS, methanolysis and oxidative cleavage of double bond. Antibacterial, antifungal, cytotoxic, phytotoxic and insecticidal activities were evaluated of compound 1, crude extract and its fractions so far for the first time. Pharmacological activities results showed that n-butanol fraction was good active against Pseudomonas aeruginosa and Salmonella typhi bacteria, and moderate active against Microsporum canis fungus. Crude extract, n-butanol and aqueous fractions showed good cytotoxicity. Moreover, compound 1, extract and all fractions showed notable phytotoxicity at higher concentrations, whereas all inactive against assayed insects. 相似文献
83.
The kinetics and mechanism of glutamic acid (GCO2H) oxidation by acid permanganate has been carried out in the absence and presence of sodium dodecyl sulphate (SDS). The surfactant enhances the reaction rate without changing the reaction mechanism. The overall rate expression for the reduction of MnVII may be written:
相似文献
84.
Structural,compositional and hardness properties of hydrogenated amorphous carbon nitride thin films synthesized by dense plasma focus device 下载免费PDF全文
Z. A. Umar R. S. Rawat R. Ahmad Z. Chen Z. Zhang J. Siddiqui A. Hussnain T. Hussain M. A. Baig 《Surface and interface analysis : SIA》2017,49(6):548-553
The hydrogenated amorphous carbon nitride (a‐CNx:H) thin films were synthesized on the SS‐304 substrates using a dense plasma focus device. The a‐CNx:H thin films were synthesized using CH4/N2 admixture gas and 20 focus deposition shots on substrates placed at different distances from the anode top. X‐ray photoelectron spectroscopy and Raman analysis confirmed different C–N bonding in the a‐CNx:H thin films. A decrease in the N/C ratio as well as the sp3/sp2 ratio with an increase in the substrate distance has been observed. The higher amount of C–N formation for the film synthesized at 10 cm is observed which decreases with increasing distance. The X‐ray photoelectron spectroscopy and Raman analysis affirmed the C ≡ N presence in all the thin films synthesized at different distances. The morphology of the synthesized a‐CNx:H thin films showed nanoparticles and nanoparticle clusters formation at the surface. The hardness results showed comparatively lower hardness of the a‐CNx:H thin films due to the presence of C ≡ N. The C–N formation with lower amount of C ≡ N and a higher N/C ratio as well as a higher sp3/sp2 ratio for the films synthesized at 10 cm show reasonably higher hardness. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
85.
Conventional lattice Boltzmann models for the simulation of fluid dynamics are restricted by an error in the stress tensor that is negligible only for small flow velocity and at a singular value of the temperature. To that end, we propose a unified formulation that restores Galilean invariance and the isotropy of the stress tensor by introducing an extended equilibrium. This modification extends lattice Boltzmann models to simulations with higher values of the flow velocity and can be used at temperatures that are higher than the lattice reference temperature, which enhances computational efficiency by decreasing the number of required time steps. Furthermore, the extended model also remains valid for stretched lattices, which are useful when flow gradients are predominant in one direction. The model is validated by simulations of two- and three-dimensional benchmark problems, including the double shear layer flow, the decay of homogeneous isotropic turbulence, the laminar boundary layer over a flat plate and the turbulent channel flow. 相似文献
86.
Muhammad Tariq Saqib Ali Muhammad Nawaz Tahir Nasir Khalid Jafir Hussain Shirazi 《Journal of the Iranian Chemical Society》2014,11(3):839-846
A series of six organotin(IV) carboxylates [Me2SnL2] (1), [n-Bu2SnL2] (2), [n-Oct2SnL2] (3), [Me3SnL] (4), n-Bu3SnL (5) and [Ph3SnL] (6), where L = 3-(4-cyanophenyl) acrylic acid have been synthesized and characterized by elemental analysis, FT-IR and NMR (1H, 13C). The complex (4) was also analyzed by single crystal X-ray analysis which showed distorted trigonal bipyramidal geometry with polymeric bridging behavior. The complexes 1–6 were screened for antimicrobial activities and cytotoxicity. The results showed significant activity with few exceptions. The catalytic activity of complexes was assessed in transesterification reaction of Brassica campestris oil (triglycerides) to produce biodiesel (fatty acid methyl esters). The results showed that triorganotin(IV) complexes exhibited good catalytic activity than their di-analogues. 相似文献
87.
Computational studies on optoelectronic and charge transfer properties of some perylene‐based donor‐π‐acceptor systems for dye sensitized solar cell applications 下载免费PDF全文
Taniya Manzoor Summera Asmi Saba Niaz Altaf Hussain Pandith 《International journal of quantum chemistry》2017,117(5)
We report DFT studies on some perylene‐based dyes for their electron transfer properties in solar cell applications. The study involves modeling of different donor‐π‐acceptor type sensitizers, with perylene as the donor, furan/pyrrole/thiophene as the π‐bridge and cyanoacrylic group as the acceptor. The effect of different π‐bridges and various substituents on the perylene donor was evaluated in terms of opto‐electronic and photovoltaic parameters such as HOMO‐LUMO energy gap, λmax, light harvesting efficiency(LHE), electron injection efficiency (Øinject), excited state dye potential (Edye*), reorganization energy(λ), and free energy of dye regeneration (). The effect of various substituents on the dye–I2 interaction and hence recombination process was also evaluated. We found that the furan‐based dimethylamine derivative exhibits a better balance of the various optical and photovoltaic properties. Finally, we evaluated the overall opto‐electronic and transport parameters of the TiO2‐dye assembly after anchoring the dyes on the model TiO2 cluster assembly. 相似文献
88.
The oxodiperoxo complexes of Mo(VI) of the type [MoO(O2)2L], where L = Morpholinomethyl urea, morpholinomethyl thiourea, piperidinomethyl urea, piperidinomethyl thiourea, pyrrolidinomethyl
urea, and pyrrolidinomethyl thiourea have been synthesized and characterized by elemental analysis, molar conductance, IR,
UV-Vis, and TGA/DTA techniques. It is shown that the ligands coordinate to the metal ion in a symmetrical bidentate fashion
through heterocyclic nitrogen and carbonyl oxygen or thiocarbonyl sulfur. Thermal studies indicate continuous weight loss
until a stable oxide is formed.
The text was submitted by authors in English. 相似文献
89.
Najeeb Ur Rehman Hidayat Hussain Samia Ahmed Al‐Riyami René Csuk Mohammed Khiat Ghulam Abbas Ahmed Al‐Rawahi Ivan R. Green Ishtiaq Ahmed Ahmed Al‐Harrasi 《Helvetica chimica acta》2016,99(8):632-635
One new diacylglycoside named lyciumaside ( 1 ) and a new sesquiterpene lactone named lyciumate ( 2 ) were isolated from Lycium shawii Roem . & Schult . The structures of the two new compounds were elucidated based on 1D‐ (1H‐ and 13C‐NMR and NOE) and 2D‐NMR (COSY, HSQC, and HMBC) spectroscopic techniques, and mass spectrometry (ESI‐MS). Preliminary evaluations demonstrated lyciumaside ( 1 ) possesses strong antioxidant activity with an IC50 = 30 μg/ml (80% inhibition) while it was inactive in α‐glucosidase and urease enzymes assays. 相似文献
90.
Polyvinylimidazole/sol–gel composite as a novel solid‐phase microextraction coating for the determination of halogenated benzenes from aqueous solutions 下载免费PDF全文
Manoochehr Farjaminezhad Mohammad Saber Tehrani Parviz Aberoomand Azar Syed Waqif Hussain Shahab Bohlooli 《Journal of separation science》2014,37(12):1475-1481
A polyvinylimidazole/sol–gel composite is proposed as a novel solid‐phase microextraction fiber to extract five halobenzenes from the headspace of aqueous solutions in combination with gas chromatography with mass spectrometry. The prepared fiber was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The obtained results showed that porous polyvinylimidazole/sol–gel composite was chemically deposited on fused silica fiber. The effect of important extraction parameters including extraction temperature, extraction time, and salt content were investigated. The optimum conditions were as follows: extraction temperature 25°C, extraction time 20 min, and salt concentration 30 w/v%. Detection limits and relative standard deviations of the developed method for halogenated benzenes were below 0.1 pg/mL and 15%, respectively. Repeatability of the proposed method, explained by relative standard deviation, varied between 5.48 and 9.15% (n = 5). The limits of detection (S/N = 3) ranged between 0.01 and 0.10 ng/L using gas chromatography with mass spectrometry with selected ion monitoring mode. For real sample analysis, three types of water samples with different matrices (ground, surface, and tap water) were studied. The optimized procedure was applied to extraction and method validation of halogenated benzenes in spiked water samples. 相似文献
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