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Fathy Fahim Abdel-latif 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):145-148
Abstract New spirothiopyran-4-yl indolidene derivatives have been synthesised via a facile one-step method. Structures and reaction mechanisms are also reported and supported by another synthetic route. 相似文献
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Spectral properties of some 2-Quinolones were investigate-ed. IR and 1H NMR were applied to characterize the ligands. The hydrogen bond property is of important parameter for controlling the behaviour of the compounds. The N[sbnd]H, O[sbnd]H, C[dbnd]O, C[sbnd]H, and C[sbnd]N fundamental functional groups are characterized. The electronic transitions are assigned. The data are explained on the basis of molecular structure and substituents effects. The acid-base equilibria and the phenomena of tautomerism for these compounds are explained and discussed. The acid exponents (pKOH, and pKNH) are evaluated. 相似文献
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R. M. Shaker A. F. Mahmoud F. F. Abdel-latif 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):207-222
Abstract The synthesis and structural characterization of 2-thioxopyrido[2,3-d]pynmidinethiones 5,9,12 and 4,4′-(1,4-phenylene)-di-(2-thioxo-1,2,3,4-tetrahydropyrimidines) 16-22 are described. 相似文献
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Diammonium hydrogen phosphate and potassium carbonate-catalyzed one-pot synthesis of 1,4- phenylene-bis(2-amino-4H-pyran-3-carbonitrile and 2-amino-4-aryl-4H-pyran-3-carbonitrile deriva- tives has been achieved by a three-component cyclocondensation of aldehydes, malononitrile, and different nucleophiles in aqueous medium in high yields. 相似文献
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M. Z. A. Badr S. A. Mahgoub F. F. Abdel-latif A. A. A. Abd El-Hafez 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):175-183
Abstract 3,5-Dicyano-6-mercapto-4-phenylpyridin-2(1H)-one (1) was reacted with ethyl chloroacetate to give compound (II) which on reaction with hydrazine hydrate gave the corresponding hydrazide derivative (III). Acylation of (III) with acetic acid, phenylisocyanate, or phenylisothiocyanate gave different monoacyl derivatives (IV-VI). Condensation of III with aromatic aldehydes and acetylacetone gave compounds VIIa-c, VIII respectively. Compound I was reacted with chloroanilides, bromoacetone and phenacyl bromide to yield the IX-XI; these and compound II gave thieno[2,3-b]-pyridines (XU-XV) on treatment with sodium ethoxide solution. Reaction of XII with acetic anhydride gave the diacetyl derivative XVI. Hydrolysis of compound XII with sodium hydroxide gave the corresponding acid (XVII) which on treatment with acetic anhydride gave the oxazine derivative (XVIII). Reaction of oxazine compound XVIII with ammonium acetate and hydrazine hydrate gave pyrido[3′,2′:4,5] thieno[3,2-d]pyrimidin-4.7-dione derivative (XIX) and (XX) respectively. The N-amino derivative (XX) was reacted with 4-nitrobenzaldehyde to give the corresponding azomethine (XXI). Significant in vitro gram-positive and gram negative antibacterial activities as well as anti-fungal effect were observed for some members of the series. 相似文献
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Rednikov AY; Zhao Hong; Sadhal SS; Trinh EH 《The Quarterly Journal of Mechanics and Applied Mathematics》2006,59(3):377-397
The steady (acoustic) streaming associated with a sphericaldrop displaced from the velocity antinode of a standing waveis studied. The ratio of the particle size to the acoustic wavelengthis treated as small but non-zero, and the solution is developedin the form of a two-term expansion in terms of the correspondingsmallness parameter. The drop viscosity is assumed to be muchhigher than that of the surrounding fluid, which is the casefor a drop in a gas medium. There are essentially three distinctregions where the steady streaming flow is analysed: insidethe drop (internal circulation), in the Stokes shear-wave layerat the surface on the gas side, and the gas outside the Stokeslayer (the outer streaming region). Solutions for the internalcirculation and the outer streaming are obtained in the limitof small Reynolds number. Despite the gas-to-liquid viscosity ratio being small, the outerstreaming may be dramatically affected by the fact that thesphere is liquid as opposed to solid. The parameter that measuresthe effect of liquidity is essentially the viscosity ratio dividedby the relative (to the particle size) thickness of the Stokeslayer. The case of a solid sphere is recovered by letting thisparameter go to zero. 相似文献
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E. Kh. Ahmed M. A. Ameen F. F. Abdel-latif 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):497-510
A highly efficient and versatile synthetic approach to the synthesis of pyrido[4′, 3′: 4]thieno[2,3-d]pyrimidines (4, 14, 15, 21) and their heterofused (e.g., triazolo-, triazino-, imidazo-, and tetrazolo-,) pyridothienopyrimidines (5–9, 16, 17, 22–24) is described utilizing 2-amino-3-cyano-4,5,6,7-tetrahydro-thieno[2,3-c]pyridine-6-carboxylic acid ethyl ester ( 2 ) and diethyl 2-isothio-cyanate-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3,6-dicarboxylate ( 10 ) as starting materials. 相似文献
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H. Mahfoz Kotb M.A. Dabban F.M. Abdel-Rahim A.Y. Abdel-latif M.M. Hafiz 《Physica B: Condensed Matter》2011,406(6-7):1326-1329
The effect of annealing in nitrogen atmosphere on structural and electrical properties of selenium rich CdSe (SR-CdSe) thin films deposited by thermal evaporation onto glass substrates were studied. X-ray diffraction (XRD) patterns showed that the as-prepared films were amorphous, whereas the annealed films were polycrystalline. Analyzing XRD patterns reveals the coexistence of both Se and CdSe crystalline phases which exhibits a hexagonal structure. The microstructure parameters (crystallite size, microstrain and dislocation density) were calculated for annealed films.Temperature dependence (300–500 K) of d.c. conductivity was studied for as-prepared and annealed thin films. The experimental results indicate that the electrical conduction taking place through thermally activated process. At higher temperatures, electrical conduction for as-prepared film is taking place in the extended states while localized states conduction in the band tails is most likely to take place for annealed films. Regarding the lower temperature range, conduction by hopping in the localized states near the Fermi level is found to be dominant. Thus, conductivity data in this range was analyzed using Mott's variable range hopping conduction, where Mott's parameters were calculated for SR-CdSe thin films. 相似文献