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51.
A Convenient Synthesis of Some New 1,3,4‐Thiadiazoles,Thiazoles, Pyrazolo[1,5‐a]pyrimidines,Pyrazolo[5,1‐c]triazine,and Thieno[3,2‐d]pyrimidines Containing 5‐Bromobenzofuran Moiety 下载免费PDF全文
Abdou O. Abdelhamid Abdelgawad A. Fahmi Basma S. Baaiu 《Journal of heterocyclic chemistry》2016,53(4):1292-1303
1,3,4‐Thiadiazoles, pyrazolo[1,5‐a]pyrimidines, pyrazolo[5,1‐c]triazine, and thieno[3,2‐d]pyrimidines were synthesized from 1‐(5‐bromobenzofuran‐2‐yl)ethanone. The structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, chemical transformation, and alternative synthesis route whenever possible. 相似文献
52.
Useful Precursors for Synthesis of Some New Azolo[3,4‐d]pyridiazines,Azolo[1,5‐a]pyrimidines,Azolo[5,1‐c]triazines,Pyrazoles, and Benzo[b][l,4]diazepine 下载免费PDF全文
Abdou O. Abdelhamid Abdelgawad A. Fahmi Basma S. Baaiu 《Journal of heterocyclic chemistry》2016,53(6):1917-1927
Pyrazolo[3,4‐d]pyridazines, isoxazolo[3,4‐d]pyridazines, azolo[1,5‐a]pyrimidines, azolo[5,1‐c]triazines, pyrazoles, and benzo[b][l,4]diazepine were synthesized from the appropriate hydrazonoyl halides, hydroximoyl halides, heterocyclic amines, diazotized heterocyclic amines, arenediazonium chlorides, and o‐phenylenediamines with appropriate of sodium 3‐(5‐bromobenzofuran‐2‐yl)‐3‐oxoprop‐1‐en‐1‐olate or 1‐(5‐bromobenzofuran‐2‐yl)‐3‐(dimethylamino)prop‐2‐en‐1‐one. The newly synthesized compounds were elucidated by elemental analyses, spectral data, and alternative synthesis whenever possible. 相似文献
53.
Electrochemical Capacitive K+ EMIS Chemical Sensor Based on the Dibromoaza[7]helicene as an Ionophore for Potassium Ions Detection 下载免费PDF全文
Moncef Tounsi Mourad Ben Braiek Abdoullatif Baraket Michael Lee Nadia Zine Miguel Zabala Joan Bausells Faouzi Aloui Béchir Ben Hassine Abderrazak Maaref Abdelhamid Errachid 《Electroanalysis》2016,28(12):2892-2899
A K+‐sensitive capacitive electrolyte‐membrane‐insulator‐semiconductor (EMIS) based on a novel dibromoaza[7]helicene ionophore has been developed. An ion‐sensitive membrane based on polyvinylchloride (PVC) doped with the ionophore was deposited on the Si3N4/SiO2/Si‐p/Cu‐Al transducer. The properties of the K+‐EMIS chemical sensor were investigated by electrochemical impedance spectroscopy (EIS). All the developed devices upon being tested have shown good sensitivity and linearity responses within the range 10?6 M to 10?1 M of potassium activity, with good selectivity over a wide variety of other cations (Na+, Li+, Cu2+, Ca2+, and Mg2+). To our knowledge, this is the first time that a capacitive field‐effect sensor has been fabricated using helicene as a carrier for K+‐detection, combined with the structure: Si3N4/SiO2/Si‐p/Cu‐Al as a transducer. 相似文献
54.
Bouafsoun A Helali S Othmane A Kerkeni A Prigent AF Jaffrézic-Renault N Bessueille F Léonard D Ponsonnet L 《Macromolecular bioscience》2007,7(5):599-610
To study cell attachment to biomaterials, several proteins such as fibronectin, collagen IV, heparin, immunoglobulin G, and albumin have been deposited onto polystyrene adsorbed on a self-assembled monolayer (silane or thiol) on glass or gold, respectively. The different steps of this multilayer assembly have been characterized by electrochemical impedance spectroscopy (EIS). These data are compared to those of adhesion rate, viability percentage, and cytoskeleton labeling for a better understanding of the cell adhesion process to each protein. All the proteins are endothelial cell adhering biomolecules but not with the same features. A linear relationship has been established between adhesion rate and resistance of the endothelial cell/protein interface for all negatively charged proteins. 相似文献
55.
56.
Zahraa Hammoud Maya Kayouka Adriana Trifan Elwira Sieniawska Jouda Mediouni Ben Jema Abdelhamid Elaissari Hlne Greige-Gerges 《Molecules (Basel, Switzerland)》2021,26(22)
The essential oil component α-pinene has multiple biological activities. However, its application is limited owing to its volatility, low aqueous solubility, and chemical instability. For the aim of improving its physicochemical properties, α-pinene was encapsulated in conventional liposomes (CLs) and drug-in-cyclodextrin-in-liposomes (DCLs). Hydroxypropyl-β-cyclodextrin/α-pinene (HP-β-CD/α-pinene) inclusion complexes were prepared in aqueous solution, and the optimal solubilization of α-pinene occurred at HP-β-CD:α-pinene molar ratio of 7.5:1. The ethanol-injection method was applied to produce different formulations using saturated (Phospholipon 90H) or unsaturated (Lipoid S100) phospholipids in combination with cholesterol. The size, the phospholipid and cholesterol incorporation rates, the encapsulation efficiency (EE), and the loading rate (LR) of α-pinene were determined, and the storage stability of liposomes was assessed. The results showed that α-pinene was efficiently entrapped in CLs and DCLs with high EE values. Moreover, Lipoid S100 CLs displayed the highest LR (22.9 ± 2.2%) of α-pinene compared to the other formulations. Both carrier systems HP-β-CD/α-pinene inclusion complex and Lipoid S100 CLs presented a gradual release of α-pinene. Furthermore, the DPPH radical scavenging activity of α-pinene was maintained upon encapsulation in Lipoid S100 CLs. Finally, it was found that all formulations were stable after three months of storage at 4 °C. 相似文献
57.
C‐Coumarinoyl‐N‐arylformohydrazonoyl bromides ( 3 ) were synthesized by reaction of N‐nitrosoarylacetamides with an appropriate sulfonium bromide in ethanol at room temperature. The reactions of potassium thiocyanate, potassium selenocyanate, thiourea, methyl phenylthiocarbomate, and methyl phenylhydrazinedithioate with hydrazonoyl bromide 3a were examined. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 355–362, 1999 相似文献
58.
This work reports on the steady state fluorescence (SSF) technique for studying film formation from surfactant‐free, nano‐sized polystyrene (PS) latex particles prepared via emulsion polymerization. The latex films were prepared from pyrene (P)‐labeled PS particles at room temperature and annealed at elevated temperatures in 5, 10, 15, 20 and 30 min time intervals above the glass transition temperature (Tg) of PS. During the annealing processes, the transparency of the film was improved considerably. Monomer and excimer fluorescence intensities, IP and IE respectively, from P were measured after each annealing step to monitor the stages of film formation. Evolution of transparency of the latex films was monitored by using photon transmission intensity, Itr. Void closure and interdiffusion stages were modeled and related activation energies were determined and found to be 10.3 and 50.3 kJ mol−1. Void closure temperatures, Tv, were determined from the minima of Itr value. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
59.
Hanna Mouaziz Sebastian Braconnot Frédéric Ginot Abdelhamid Elaissari 《Colloid and polymer science》2009,287(3):287-297
Aminodextran containing submicron magnetic latex particles were prepared in two steps: (a) transformation of oil-in-water
magnetic emulsion into structured magnetic latex particles via combination of seed and miniemulsion-like polymerization process
and (b) immobilization (adsorption and chemical grafting) of prepared aminodextran onto negatively charged seed magnetic latex
particles. The elaborated magnetic latex particles were characterized in terms of particle size, size distribution, morphology,
surface charge density, chemical composition, magnetic properties, and also colloidal stability. The results showed that the
morphology of the prepared seed magnetic latex is core–shell like and the cationic latex particles are hydrophilic and of
high colloidal stability, irrespective of the aminodextran immobilization process. 相似文献
60.
Joumaa N Lansalot M Théretz A Elaissari A Sukhanova A Artemyev M Nabiev I Cohen JH 《Langmuir : the ACS journal of surfaces and colloids》2006,22(4):1810-1816
Submicrometer fluorescent polystyrene (PS) particles have been synthesized via miniemulsion polymerization using CdSe/ZnS core-shell quantum dots (QDs). The influence of QD concentration, QD coating (either trioctylphosphine oxide (TOPO)-coated or vinyl-functionalized), and surfactant concentration on the polymerization kinetics and the photoluminescence properties of the prepared particles has been analyzed. Polymerization kinetics were not altered by the presence of QDs, whatever their surface coating. Latexes exhibited particle sizes ranging from 100 to 350 nm, depending on surfactant concentration, and a narrow particle size distribution was obtained in all cases. The fluorescence signal of the particles increased with the number of incorporated TOPO-coated QDs. The slight red shift of the emission maximum was correlated with phase separation between PS and QDs, which occurred during the polymerization, locating the QDs in the vicinity of the particle/water interface. QD-tagged particles displayed higher fluorescence intensity with TOPO-coated QDs compared to those with the vinyl moiety. The obtained fluorescent particles open up new opportunities for a variety of applications in biotechnology. 相似文献