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101.
102.
Wael S. I. Abou-Elmagd Ahmed K. EL-Ziaty Magdy I. Elzahar Sayed K. Ramadan Ahmed I. Hashem 《合成通讯》2016,46(14):1197-1208
Pyrazolyl-substituted 2(3H)-furanone was allowed to react with different nitrogen nucleophiles such as hydrazine hydrate, ethylenediamine, ethanolamine, and anthranilic acid to give pyrrolone and benzoxazinone derivatives. The acid hydrazide 3 was reacted with some carbonyl compounds such as 4-chlorobenzaldehyde, chloroacetyl chloride, and acetic anhydride to give thiazolidinone, oxadiazole, and pyridazinone derivatives. Selected examples of the synthesized compounds were evaluated as anticancer agents against three types of carcinoma cell lines (HePG 2, HCT116, and PC3), using Doxorubicin as a reference drug. The result revealed that some of the new compounds showed high activities. Compound 6a was more potent than the standard drug. A docking study using MOE 2008.10 program was performed. 相似文献
103.
Amiri AA Hemmateenejad B Safavi A Sharghi H Beni AR Shamsipur M 《Analytica chimica acta》2007,605(1):11-19
The reversed-phase high-performance liquid chromatographic (RP-HPLC) behavior of some newly synthesized hydroxythioxanthone derivatives using binary acetonitrile-water mixtures as mobile phase has been examined. First, the variation in the retention time of each molecule as a function of mobile phase properties was studied by Kamlet-Taft solvatochromic equations. Then, the influences of molecular structure of the hydroxythioxanthone derivatives on their retention time in various mobile phase mixtures were investigated by quantitative structure-property relationship (QSPR) analysis. Finally, a unified model containing both the molecular structure parameters and mobile phase properties was developed to describe the chromatographic behavior of the systems studied. Among the solvent properties, polarity/polarizability parameter (π*) and hydrogen-bond basicity (β), and among the solute properties, the most positive local charge (MPC), the sum of positive charges on hydrogen atoms contributing in hydrogen bonding (SPCH) and lipophilicity index (log P) were identified as controlling factors in the RP-HPLC behavior of hydroxythioxanthone derivatives in actonitrile-water binary solvents. 相似文献
104.
N. A. Hassan M. I. Hegab F. M. Abdel‐Motti S. H. A. Hebah F. M. E. Abdel‐Megeid A. I. Hashem 《Journal of heterocyclic chemistry》2007,44(4):775-782
105.
The effect of different chromatographic conditions, such as buffer concentration and type of organic modifier, on the retention behavior of nine tricyclic neuroleptics on three different RP-HPLC columns was investigated. Two recently developed columns, calixarene-bonded (CALTREX) AIII) and monolithic (Chromolith) Performance RP-18e) columns, were compared with a conventional RP-C18 HPLC column (LiChrospher). The results showed how the mobile phase conditions had different effects on the analyte retention on these three columns. For example, the elution order of some analytes and the initiation of separation of the geometric isomers of the three analytes--which have E/Z-isomers (cis/trans-isomers)--could be altered by changing the conditions and the column type. Under identical conditions, a calixarene-bonded phase was the best for this separation, a monolithic phase gave comparable results and the conventional RP-column was the least effective. Concerning the geometric isomers separation, the Chromolith Performance RP-18e was superior. 相似文献
106.
In this study, a method for enantioseparation of terbutaline and salbutamol was established using Chirobiotic V column as a stationary phase. Polar ionic mode applying mobile phase containing ammonium nitrate in 100% ethanol, pH 5.1 was found to give the best separation. The salt concentration in the mobile phase and pH value were found to be the most important chromatographic factors affecting separation. Separation of enantiomers of these two basic analytes was complete in less than 10 min without applying ammonium trifluoroacetate (ATFA) or triethylamine (TEA) salts. 相似文献
107.
Nasim Asghari Lalami Hassan Hosseini Monfared Hashem Noei Peter Mayer 《Transition Metal Chemistry》2011,36(6):669-677
Three new binuclear vanadium(V) complexes of bis(aryl)adipohydrazones (H4L1 = bis((2-hydroxynaphthalen-1-yl)methylene)adipohydrazide, H4L2 = bis(5-bromo-2-hydroxybenzylidene)adipohydrazide, and H4L3 = bis(2-hydroxy-3-methoxybenzylidene)adipohydrazide) were synthesized by direct reaction of [VO(acac)2] with the hydrazone ligands. The ligands and complexes were characterized by FT–IR, UV–Vis, and NMR spectroscopic methods.
The crystal structures of the complexes of L1 and L3 were determined by X-ray analyses. The solid-state structure of the complex of L1 features a 1D hydrogen-bonded chain from N⋯H–O hydrogen bonding. The catalytic activities of these complexes have been tested
in the oxidation of various hydrocarbons using H2O2 as the terminal oxidant. Generally, good to excellent conversions have been obtained. 相似文献
108.
Saeed Golmohammadi Hashem Imani Amin Khalafi Ghader Karimian Ali Rostami 《Fiber and Integrated Optics》2013,32(3):178-191
Abstract Resolution enhancement of a high-speed fiber-optic spectrometer is investigated in this article. The operation of these types spectrometers is based on conversion of the spectral-domain signal into the time domain by a dispersive element. A photonic crystal fiber is used as a dispersive fiber in this spectrometer. Resolution enhancement of considered spectrometer with photonic crystal fibers is studied. The fiber loss and length minimization in this spectrometer are obtained. Simulation results show that an increase in resolution will cause a decrease in the speed of the spectrometer. Trade offs between resolution and speed are studied. 相似文献
109.
A novel, simple, sensitive and selective spectrofluorimetric method was developed for the determination of trace amounts of
chlorzoxazone and Ibuprofen in pharmaceutical tablets using optical sensor Eu-Tetracycline HCl doped in sol–gel matrix. The
chlorzoxazone or Ibuprofen can remarkably enhance the luminescence intensity of Eu-Tetracycline HCl complex doped in a sol–gel
matrix in dimethylformamide (DMF) at pH 9.7 and 6.3, respectively, λex = 400 nm. The enhancing of luminescence intensity peak of Eu-Tetracycline HCl complex at 617 nm is proportional to the concentration
of chlorzoxazone or Ibuprofen a result that suggested profitable application as a simple optical sensor for chlorzoxazone
or Ibuprofen assessment. The dynamic ranges found for the determination of chlorzoxazone and Ibuprofen concentration are 5 × 10−9–1 × 10−4 and 1 × 10−8–7 × 10−5 mol L−1, and the limit of detection (LOD) and quantitation limit of detection (LOQ) are 3.1 × 10−10 , 9.6 × 10−10 and 5.6 × 10−10, 1.7 × 10−9 mol L−1, respectively. 相似文献
110.
Kah-Yoong Chan Elias Hashem Aad Gordijn Helmut Stiebig Dietmar Knipp 《Applied Physics A: Materials Science & Processing》2009,96(3):751-758
Hydrogenated microcrystalline silicon has recently emerged as a promising material system for large-area electronic applications
such as thin-film transistors and solar cells. In this paper, thin-film transistors based on microcrystalline silicon were
realized with charge carrier mobilities exceeding 40 cm2/Vs. The electrical characteristics of the microcrystalline silicon thin-film transistors are limited by the influence of
contact effects. The influence of the contact effects on the charge carrier mobility was investigated for transistors with
different dimensions of the drain and source contacts. The experimental results were compared to an electrical model which
describes the influence of the drain and source contact dimension on the transistor parameters. Furthermore, the Transmission
Line Method was applied to investigate the contact effects of the thin-film transistors with different drain and source contact
dimensions. Finally, optimized device geometries like the channel length of the transistor and dimension of the drain and
source contacts were derived for the microcrystalline transistors based on the electrical model. 相似文献