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31.
Abdou O. Abdelhamid Hamdi M. Hassaneen Ikhlass M. Abbas Ahmad S. Shawali 《Tetrahedron》1982,38(10):1527-1530
Diazotized anathranilic acid and its methyl ester react with substituted α-thiocyanatoacetoacetanilides3a–c to give in both cases the corresponding thiadiazolo [2,3-b] quinazolines6a–c, respectively. A mechanism is proposed and it is substantiated by synthesis of6a from N-(2-car?yphenyl)-C-phenylcarbamoyl hydrazidoyl chloride8a or its N-(2-methoxycarbonylcarbonylphenyl) analogue8d. 相似文献
32.
Ahmad S. Shawali Abdou O. Abdelhamid Hamdi M. Hassaneen Abdelfattah Shetta 《Journal of heterocyclic chemistry》1982,19(1):73-75
Diazotized anthranilic acid and its methyl ester react with substituted phenacyl thiocyanates 3 to give in both cases the corresponding thiadiazolo[2,3-b]quinazolines 7a-e . A mechanism is proposed and it is substantiated by alternate synthesis of 7a from the hydrazidoyl chlorides 9a,b and potassium thiocyanate. 相似文献
33.
Muz MH Deveci F Bulut Y Ilhan N Yekeler H Turgut T 《Experimental & molecular medicine》2006,38(2):109-118
Airway structural changes that occur in patients with asthma in response to persistent inflammation are termed airway remodeling. The cysteinyl leukotrienes (LTC(4), D(4) and E(4)) are known to play important roles in the pathobiology of asthma. To evaluate the effect of low dose montelukast (MK) on the development of airway remodeling using a chronic murine model of allergic airway inflammation with subepithelial fibrosis, BALB/c mice, after intraperitoneal ovalbumin (OVA) sensitization on days 0 and 14, received intranasal OVA periodically on days 14-75. MK treated mice received montelukast sodium intraperitoneally on days 26-75. The OVA sensitized/challenged mice developed an extensive eosinophil cell inflammatory response, goblet cell hyperplasia, mucus occlusion, and smooth muscle hypertrophy of the airways. In addition, in OVA sensitized/challenged mice, dense collagen deposition/fibrosis was seen throughout the lung interstitium surrounding the airways, blood vessels, and alveolar septae. The cysteinyl leukotriene 1 (CysLT1) receptor antagonist, MK significantly reduced the airway eosinophil infiltration, goblet cell hyperplasia, mucus occlusion, and lung fibrosis except airway smooth muscle hypertrophy in the OVA sensitized/challenged mice. The OVA sensitized/challenged mice had significantly increased epithelial desquamation compared with control mice. MK markedly reduced epithelial desquamation of airways in OVA/MK treated animals compared with OVA sensitized/challenged mice. MK treatment did not affect the levels of CysLT in lung tissue. Our results show that the important role of cysteinyl leukotrienes in the pathogenesis of asthma. Lower dose of CysLT1 receptor antagonism has a significant anti-inflammatory effect on allergen-induced lung inflammation and fibrosis but not airway smooth muscle hypertrophy in an animal model of asthma. 相似文献
34.
Density functional calculations on XYYX and X2YY isomers of the X2Y2 species (X: H, Li, Na, F, Cl, Br, I; Y: O, S, Se, Te) show that the XYYX isomers are more stable than the X2YY forms except for X = F and Y = S and Te, for which the F2SS and F2TeTe isomers are slightly more stable. 相似文献
35.
Boubakri L. Al-Ayed Abdullah S. Mansour L. Harrath A. A. Al-Tamimi J. Özdemir I. Yasar S. Hamdi N. 《Transition Metal Chemistry》2019,44(4):321-328
Transition Metal Chemistry - The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare unsymmetrical arylpyridine ketones has been carried out using... 相似文献
36.
Clément Ghiazza Moussa Ndiaye Anfal Hamdi Anis Tlili Thierry Billard 《Tetrahedron》2018,74(45):6521-6526
Herein, the direct C-5 fluoroalkylselenolation of 8-aminoquinolines is described. The Pd-catalyzed reaction is performed with the in situ generated fluoroalkylselenyl chloride and various 8-aminoquinoline amides or sulfonamides. The desired products were formed in moderate to excellent yields. 相似文献
37.
Hamdi Ben Halima Abdelhamid Errachid Nicole Jaffrezic-Renault 《Electroanalysis》2023,35(1):e202100451
The review presents advances and main challenges of the affinity sensors based on field- effect transistors published during the last five years. The different nanomaterial-based field-effect transistors are classified according to the nature of the nanomaterials, beginning by silicon, the “gold-standard” semiconductor, the gallium nitride semiconductor, the organic semiconductors, the silicon nanowires, the inorganic nanomaterials, the carbon nanotubes and the graphene. Due to its exceptional electrical properties, the main works are devoted to graphene. The obtained analytical performances for the detection of biomarkers, of DNA sequences and of miRNA are listed. The relation between the operational conditions - nature of the nanomaterials, procedure of preparation, choice of the receptor molecule, method of immobilization – and the analytical performance are discussed. The perspective of industrialization of these affinity sensors based on field-effect transistors is discussed. 相似文献
38.
Abdelwaheb Hamdi Young Hoon Lee Dewi K.A. Kusumahastuti Rym Abidi 《Tetrahedron letters》2009,50(5):540-551
The synthesis and complexation properties of a novel type of calix[4]azacrown, in which two cone calix[4]arenes are linked via a spiro C-atom incorporated into polyaminoalkylene chains are presented. 相似文献
39.
Hamdi Raïssi 《Comptes Rendus Mathematique》2011,349(21-22):1203-1206
This Note is devoted to the test of instantaneous linear Granger causality when the errors are dependent but uncorrelated. The assumptions are weak and include a large set of dynamics as for instance the GARCH processes. We show that the standard Wald test for testing instantaneous linear Granger causality is not valid in our framework. As a consequence Wald tests which are valid in our framework are proposed. 相似文献
40.