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81.
Synthesis,Crystal Structure,and Antibacterial Activity of 1,2,4‐Triazoles and 1,2,4‐Triazol‐3‐one 下载免费PDF全文
Bochra Ben Salah Najla Chaari Awatef Rekik Anis Ben Hsouna Mohamed Trigui Mohamed Kossentini 《Journal of heterocyclic chemistry》2015,52(6):1769-1775
A straightforward method has been developed for the synthesis of 1,2,4‐triazol‐3‐one 3 and 1,2,4‐triazoles 6a , 6b , 6c , 6d starting from N1‐substituted‐N1‐tosylhydrazonates 2 and hydrazine monohydrate. This methodology affords a number of 1,2,4‐triazol‐3‐one 3 and 1,2,4‐triazoles 6a , 6b , 6c , 6d in reasonable yields. The structures of all new compounds were elucidated using infrared, 1H and 13C NMR, high‐resolution mass spectrometry, elemental analysis, and the X‐ray crystallography (for compounds 3 and 6a ). Some of the newly synthesized compounds were screened for their antibacterial activity. 相似文献
82.
Exploiting the 1,2,3‐Triazole Moiety to Generate Carbazole Molecular Architectures through Click Approach 下载免费PDF全文
Mohamed A. Ameen Kamal M. El‐Shaieb Asmaa H. Mohamed Fathy F. Abdel‐Latif 《Journal of heterocyclic chemistry》2015,52(6):1718-1722
Reaction of 3,6‐dichlorocarbazole with propargyl bromide in the presence of a basic medium gave an N‐propargylated carbazole. The latter compound was converted into molecular architectures containing 1,2,3‐triazole moiety through Cu(I)‐catalyzed 1,3‐cycloaddition reaction with different azides. Similarly, 2‐azidomethyl benzothiazole was cliched with N‐Boc‐protected N´‐propargyl glutamate to give the biomolecule 2‐triazolylmethyl product. 相似文献
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Fathy M. Abdelrazek Mohamed S. Farghaly Hussein E. Abdelrahman 《Journal of heterocyclic chemistry》2015,52(1):163-168
The xylidines 1a , 1b undergo condensation with ethyl cyanoacetate 2 and ethyl benzoyl acetate 15 to afford the cyano acetanilides 3a , 3b and the β‐diketones 16a , 16b , respectively. Compounds 3a , 3b react with hydrazine and phenyl hydrazine to afford the azine‐bis derivatives 5a , 5b and 7a , 7b , whereas 16a , 16b react with the same reagents to afford the pyrazolyl amine derivatives 17a , 17b and 18a , 18b , respectively. Compounds 3a , 3b react also with dimethylformamide dimethylacetal to afford the enaminonitriles 8a , 8b , whereas 16a , 16b react with the same reagent to afford only the enaminone 19b . The enaminonitriles 8a , 8b react with hydrazine and phenyl hydrazine to afford also the azine‐bis derivatives 11a , 11b and 14a , 14b , respectively. 相似文献
84.
Julien Huser Sophie Bistac Christelle Delaite Didier Dentel Mickaël Derivaz Mohamed Zanouni 《Surface and interface analysis : SIA》2015,47(4):523-528
The grafting of trialkoxysilane molecules should also give rise to the formation of a siloxane network at the substrate's surface when trialkoxysilanes are used. Other candidates that might be able to act as adhesion promoters at metallic surfaces are dimethylalkoxysilanes. The advantage of dimethylalkoxysilanes is that only one silanol group is produced during the hydrolysis step, leading to the formation of a grafted monolayer onto the steel. Moreover, the chemical grafting of stainless steel, which exhibits a low surface reactivity, is of great interest for industrial applications such as adhesive bonding or coatings. The objective of this work was to chemically graft dimethylalkoxysilanes onto AISI 316L stainless steel and to analyze the grafted layer by X‐ray photoelectron spectroscopy (XPS). Investigation of the hydrolysis of these molecules in aqueous solutions was also performed by proton nuclear magnetic resonance spectroscopy (1H NMR). The grafting of 3‐(ethoxydimethylsilyl)propylamine (APDES) and 3‐glycidoxypropyldimethylethoxysilane (GPDES) was achieved onto stainless steel after a controlled hydrolysis reaction. A pH inferior or equal to 5 was necessary to obtain a sufficient hydrolysis of silanes. XPS results have evidenced the grafting of the silanes onto stainless steel. The signal of the Si 2p peak clearly showed the formation of a covalent bond between APDES and the stainless steel surface through the O atoms giving rise to a uniform layer of adsorbed molecules. Moreover, this grafted layer is strongly stable as no removal of the alkoxysilane was observed after immersion in hot water which is very critical for these molecules. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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M. S. A. Rani N. S. Mohamed 《International Journal of Polymer Analysis and Characterization》2015,20(6):491-503
In the present work, an attempt has been made to prepare a new natural biopolymer blend electrolyte of carboxymethyl cellulose/chitosan impregnated with NH4NO3 by the solution casting technique. The conductivity for the system was measured by impedance spectroscopy. The incorporation of 40 wt.% NH4NO3 optimized the ambient temperature conductivity of the electrolyte up to 1.03 × 10?5 S cm?1. All electrolytes were found to follow the Arrhenius relationship. Dielectric studies confirmed that the electrolytes obey non-Debye behavior. The temperature dependence of the power law exponent s for the highest conducting film can be represented by the correlated barrier hopping model. 相似文献
88.
Selective and Simultaneous Determination of Dihydroxybenzene Isomers Based on Green Synthesized Gold Nanoparticles Decorated Reduced Graphene Oxide 下载免费PDF全文
Selvakumar Palanisamy Chelladurai Karuppiah Shen‐Ming Chen K. Muthupandi R. Emmanuel P. Prakash Mohamed S. Elshikh M. Ajmal Ali Fahad M. A. Al‐Hemaid 《Electroanalysis》2015,27(5):1144-1151
In the present study, we report the simultaneous electrochemical determination of hydroquinone (HQ), catechol (CC) and resorcinol (RC) at gold nanoparticles (Au‐NPs) decorated reduced graphene oxide (RGO) modified electrode. An enhanced and well defined peak current response with a better peak separation of HQ, CC and RC is observed at RGO/Au‐NPs composite than that of RGO and Au‐NPs modified electrodes. The fabricated modified electrode shows a wide linear response in the concentration range of 3–90 µM, 3–300 µM and 15–150 µM for HQ, CC and RC, respectively. The detection limit of HQ, CC and RC is found as 0.15 µM, 0.12 µM and 0.78 µM, respectively. 相似文献
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