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91.
Chickiyan Sivakumar A. Sultan Nasar 《Journal of polymer science. Part A, Polymer chemistry》2009,47(13):3337-3351
Novel AB2‐type azide monomers such as 3,5‐bis(4‐methylolphenoxy)carbonyl azide (monomer 1) , 3,5‐bis(methylol)phenyl carbonyl azide (monomer 2) , 4‐(methylol phenoxy) isopthaloyl azide (monomer 3) , and 5‐(methylol) isopthaloyl azide (monomer 4) were synthesized. Melt and solution polymerization of these monomers yielded hydroxyl‐ and amine‐terminated hyperbranched polyurethanes with and without flexible ether groups. The structures of theses polymers were established using FT‐IR and NMR spectroscopy. The molecular weights (Mw) of the polymers were found to vary from 3.2 × 103 to 5.5 × 104 g/mol depending on the experimental conditions used. The thermal properties of the polymers were evaluated using TGA and DSC: the polymer obtained from monomer ( 1 ) exhibited lowest Tg and highest thermal stability and the polymer obtained from monomer ( 2 ) registered the highest Tg and lowest thermal stability. All the polymers displayed fluorescence maxima in the 425–525 nm range with relatively narrow peak widths indicating that they had pure and intense fluorescence. Also, the polymers formed charge transfer (CT) complexes with electron acceptor molecules such as 7,7,8,8‐tetracyano‐quino‐dimethane (TCNQ) and 1,1,2,2‐tetracyanoethane (TCNE) as evidenced by UV‐visible spectra. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3337–3351, 2009 相似文献
92.
Ress DK Baytas SN Wang Q Muñoz EM Tokuzoki K Tomiyama H Linhardt RJ 《The Journal of organic chemistry》2005,70(20):8197-8200
A sTn double C-glycoside, sTn analogue 2, was synthesized using samarium chemistry developed in our laboratory. Complications in the oxidation reaction affording aldehyde acceptor were overcome by double protection of amide and the use of a room-temperature ionic liquid as solvent. Studies are underway to conjugate the sTn double C-glycoside hapten 2 to KLH carrier protein for biological evaluation as a vaccine. 相似文献
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95.
A novel hydrogel based on poly(sulfopropylmethacrylate) (p(SPM) with different crosslinking degrees was synthesized and characterized. The prepared hydrogels were for the first time, utilized for in situ metal nanoparticle preparation such as Ni, Co, and Cu and employed as a reaction media in catalytic reduction of 4-nitrophenol (4-NP), and 2-nitrophenol (2-NP) to 4-aminophenol and 2-aminophenol, respectively. The experimental parameters that effect reduction rates such as temperature and the amount of catalyst were investigated. The kinetics of the reduction reaction of nitro compounds under different reaction conditions were investigated to determine the activation parameter. Activation energies were found as 33.86 kJ mol? 1 and 24.96 kJ mol? 1 for 4-NP and 2-NP, respectively. It was found that hydrogel–Cu composites can provide 98% activity even at the end of the 7th repetitive usage. 相似文献
96.
Aeysha Sultan 《合成通讯》2014,44(3):417-423
An efficient free radical–mediated intramolecular cyclization strategy has been developed for the synthesis of 3-aryl-5-chloroindan-1-ones. Variously substituted 2,4-dichloroenones afforded 3-aryl-5-chloroindan-1-ones in quantitative yields upon intramolecular cyclization under free radical conditions. 相似文献
97.
Sultan Erkan 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(2):445-452
Russian Journal of Physical Chemistry A - F8BT, which is highly conjugated with therapeutic proteins for light emitting and targeted drug delivery, has been investigated theoretically and... 相似文献
98.
Nussupov K. Kh. Beisenkhanov N. B. Bakranova D. I. Keinbay S. Turakhun A. A. Sultan A. A. 《Physics of the Solid State》2020,62(1):48-53
Physics of the Solid State - The influence of deposition parameters, such as: the magnetron power in the range 690–1400 W, the silicon substrate temperature 23–170°C, the N2 gas... 相似文献
99.
A. M. Soliman A. A. Sultan Omran Abd Ellah A. K. El-Shafei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1301-1314
1-Anilinocycloalkanecarbonitriles 1a–c were prepared and reacted with active methylene reagents to give compounds 5a–c through 10a–c and reacted with different other reagents such as benzaldehyde, ethyl aminoacetate, ethyl mercaptoacetate, or hydrazine carbothioamide, which afforded the desired spiro heterocycles compounds 11a–c through 14a–c. 相似文献
100.
Ahmed Abdel-Lateff Tatsufumi Okino Walied M. Alarif Sultan S. Al-Lihaibi 《Journal of Saudi Chemical Society》2013,17(2):161-165
A marine fungal isolate, identified as Drechslera sp., was mass cultivated and found to produce a new naturally occurring seco-sativene type sesquiterpene helminthosporic acid (1) and three known sesquiterpenes, helminthosporol (2), drechslerine A (3) and (+) secolongifolene-diol (4). The structures of all compounds were determined by interpretation of their spectroscopic data 1D (1H and 13C), 2D (COSY, DQF, NOE, HSQC and HMBC) NMR, MS, UV and IR analyses. All compounds have been tested toward antioxidants, antimicrobial and antifouling effects. 相似文献