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991.
Naijue Zhu Danielle Lightsey Maryam Foroozesh William Alworth Amit Chaudhary Kristine L. Willett Cheryl L. Klein Stevens 《Journal of chemical crystallography》2006,36(5):289-296
Cytochrome P450 enzymes protect the body from foreign substances through a mechanism that involves oxidation of those substances into more readily excretable polar compounds. It has been shown that some naphthoflavones function as substrates of certain P450 enzymes (CYP1A1 and CYP1B1) and with appropriate structural changes may become inhibitors. Moreover, propargyl ether derivatives of adamantane have been shown to function as selective inactivators of some P450 enzymes (CYP2B1 and CYP2B5). In an attempt to improve the potency and selectivity of inhibition, we have designed and synthesized a series of naphthoflavone propargyl ethers. We report here the synthesis, X-ray crystal structures, and inhibition data (IC50 of EROD inhibition in CYP1A1 and CYP1B1 enzymes) of α-naphthoflavone 2′-propargyl ether, β-naphthoflavone 2′-propargyl ether, α-naphthoflavone 4′-propargyl ether, and β-naphthoflavone 4′-propargyl ether. Crystallographic data: α-naphthoflavone 2′-propargyl ether, , a=7.775(1) ?, b=8.062(1) ?, c=13.110(1) ?, α=84.32(1)°, β=75.42(1)°, γ=86.56(1)°, V=790.8(2) ?3; β-naphthoflavone 2′-propargyl ether, , a=7.605(2) ?, b=7.793(1) ?, c=14.167(2) ?, α=77.06(1)°, β=75.41(1)°, γ=89.54(1)°, V=790.9(2) ?3; α-naphthoflavone 4′-propargyl ether, P21/n, a=14.595(2) ?, b=4.708(1) ?, c=24.745(6) ?, β=106.31(2)°, V=1631.8(7) ?3; β-naphthoflavone 4′-propargyl ether, P1, a=4.8871(5) ?, b= 7.9597(7) ?, c=21.788(3) ?, α=81.771(9)°, β=89.918(10)°, γ=72.223(8)°, V= 797.9(2) ?3. 相似文献
992.
Zahra Mohammadzahery Maryam Jandaghi Samira Alipour Siamak Dadras Shahram Kazemi Jamshid Sabbaghzadeh 《Optics & Laser Technology》2012,44(4):1095-1100
This study deals with the thermal characterization of a continuous wave (CW-) and end-pumped passively Q-switched microchip Nd:YAG laser crystal by solving the rate and heat transfer equations in the laser cavity. In this approach, a parametric study has been performed to investigate the influence of the pumping parameters, cooling metal dimension and also the crystal dimension and doping concentration on the thermal behavior of the laser crystal. Obtained results reveal a closed correlation between the mentioned parameters and the thermal behavior of the crystal indicating that a proper selection of the laser parameters is essential to control the crystal's temperature and improve the performance of the laser accordingly. 相似文献
993.
Maryam Vosough Nahal Rahimdoost Mojdehi Amir Salemi 《Journal of separation science》2012,35(24):3575-3585
In the present study, dispersive liquid–liquid microextraction followed by high performance liquid chromatography‐diode array detection has been developed as simple, rapid, accurate, and efficient sample preparation method for simultaneous determination of seven organic UV filters in urine samples. The influence of the main effects as well as their interactions was studied through a 2(6–2) fractional factorial design. The candidate parameters were: type and volume of dispersant and extraction solvents, sample pH, and salt concentration. Under final optimal conditions, the analytes were extracted from 5 mL of samples by addition of 0.5 mL of acetonitrile (dispersing solvent) containing 70 μL of carbon tetrachloride (extraction solvent), without modifying the pH of the solution and applying the (+1) level of salt concentration (10% w/v NaCl). The assay was linear (R2 > 0.997), relative recoveries ranged from 86.9 up to 97.3% and the LOQs between 3 and 45 ng mL?1 were obtained. The intra‐ and interday RSDs were lower than 5 and 8% at the middle point of the linear range, respectively. The proposed method was successfully applied to different volunteer urine samples and it was shown that the extraction efficiency was not affected by the type of urine samples. 相似文献
994.
Mohammad Ali Zolfigol Maryam Hajjami Arash Ghorbani-Choghamarani 《Journal of the Iranian Chemical Society》2012,9(1):13-18
Poly(4-vinylpyridinium tribromide) was found to be an efficient oxidizing polymer for the chemoselective oxidation of a wide range of alcohols into aldehydes and ketones. In addition it was used for the oxidative deprotection of trimethylsilyl ethers into alcohols or carbonyl compounds depending on the structure of trimethylsilyl ether. 相似文献
995.
Mohammad Yousefi Mojdeh Safari Maryam Bikhof Torbati Vahid Molla Kazemiha Hassan Sanati Amir Amanzadeh 《应用有机金属化学》2012,26(8):438-444
Since organotin complexes have been reported to show fewer side effects relative to other heavy metal anticancer compounds, in the present study we report for the first time four novel organotin(IV) derivatives with the general formula R2SnL2, where R = methyl (1), n‐butyl (2), phenyl (3), benzyl (4) and L = morpholine‐1‐carbodithioate (MCDT). The newly synthesized ligand was monodentate or bidentate, coordinating through a sulfur atom. The complexes were synthesized by directly mixing, refluxing and stirring the ligand, with diorganotin(IV) dichlorides in a suitable solvent. The complexes were found to be pure and their solid and solution phase structural configuration was investigated by FT‐IR, multinuclear NMR (1 H, 13 C, 119Sn) and mass spectrometry. Complex 2 was also studied for its thermal decomposition by thermogravimetry and differential thermal analysis. The results obtained on the basis of these techniques are in full concurrence with the proposed 1:2 (Sn:L) stoichiometry. The cytotoxic activity of the MCDT and diorganotin(IV) complexes (1–4) was tested against tumor cell lines – human cervix carcinoma HeLa and human myelogenous leukemia K562 – and normal immunocompetent cells: peripheral blood mononuclear cells PBMC. Results of bioassay demonstrated that organotin derivatives were in general more active than the anticancer drug cisplatin. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
996.
Hossein Reza Darabi Maryam Mirza-Aghayan Laleh Ali-Saraie Mohammad Bolourtchian Bernhard Neumüller Mitra Ghassemzadeh 《Supramolecular chemistry》2013,25(1):55-58
Stilbenophanes 1c and 2c were synthesized in good yields. Among alkali ions, both isomers only formed 1:1 complexes with lithium selectively. An X-ray structure of 1c shows a statistical disorder which leads to two refined positions for the ethylene moiety. The existence of a weak intramolecular C-H > O hydrogen bond in its structure was confirmed by both X-ray analysis and theoretical calculation. 相似文献
997.
Seyed Meysam Baghbanian Yaser Babajani Hamed Tashakorian Samad Khaksar Maryam Farhang 《Comptes Rendus Chimie》2013,16(2):129-134
In this work, a green, simple and highly efficient procedure for the synthesis of bis(indolyl)methanes is described. The condensation of indoles catalyzed by p-sulfonic acid calix[4]arene in water and under solvent-free conditions afford the title compounds in high yields and relatively short reaction times. 相似文献
998.
Elmira Solati Maryam Mashayekh Davoud Dorranian 《Applied Physics A: Materials Science & Processing》2013,111(3):689-694
Electrically pumped ultraviolet random lasing was achieved in metal-insulator-semiconductor (MIS) diodes based on ZnO films at room temperature. The ZnO films were grown by plasma assisted molecular beam epitaxy. Two different kinds of insulator layers, SiO x (0<x≤2) and AlO x (0<x≤1.5) were deposited by electron beam evaporation. X-ray diffraction experiments found these oxide layers were amorphous (or microcrystals), and X-ray photoelectron spectroscopy confirmed the Si and Al were fully oxidized. Compared with devices using SiO x as the insulator layer, diodes with evaporated AlO x layers showed a lower working threshold forward current (~20 mA to ~26 mA) and higher emission intensity. Periodic features indicating formation of closed-loop paths were deduced by the power Fourier transform of electroluminescence spectra. The cavity length of both devices increased as forward currents increased, while a larger cavity length was always obtained in the AlO x -involved device under the same working current. The improved performance was attributed to larger hole amount in AlO x layers. These results revealed that evaporated AlO x can serve as good electron blocking and hole supplying layers for hetero-structures. 相似文献
999.
Reduction of a variety of imine compounds with triethylsilane in the presence of catalytic amounts of palladium(II) acetate in ethanol resulted in the formation of the corresponding amines in excellent yields after short reaction times. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
1000.
In this article, a simple, general and novel method for the synthesis of diaryl (dialkyl) disulfides from aryl (alkyl) halides is described. This is a convenient approach that involves the use of commercially available and inexpensive thioacetamide as a sulfur transfer reagent in the domino process for the synthesis of symmetric organic disulfides. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献