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81.
New series of furosalicylic acids 3a-c, furosalicylanilides 6a-n, furobenzoxazines 8a-f, 1-benzofuran-3-arylprop-2-en-1-ones 12a,b, 6-(aryl-3-oxoprop-1-enyl)-4H-chromen-4-ones 16a-c and 6-[6-aryl-2-thioxo-2,5-dihydropyrimidin-4-yl]-4H-chromen-4-ones 17a-c were synthesized. Anti-inflammatory activity evaluation was performed using carrageenan-induced paw edema model in rats and prostaglandin E(2) (PGE(2)) synthesis inhibition activity. Some of the tested compounds revealed comparable activity with less ulcerogenic effect than Diclofenac at a dose 100 mg/kg. All the synthesized compounds were docked on the active site of cyclooxygenase-2 (COX-2) enzyme and most of them showed good interactions with the amino acids of the active site comparable to the interactions exhibited by Diclofenac. 相似文献
82.
A highly sensitive disposable screen-printed butyrylcholine (BuCh) potentiometric sensor, based on heptakis (2,3,6-tri-o-methyl)-β-cyclodextrin (β-CD) as ionophore, was developed for butyrylcholinesterase (BuChE) activity monitoring. The proposed sensors have been characterized and optimized according to the constituents of homemade printing carbon ink including β-CD, anionic sites, and plasticizer. The fabricated sensor showed Nernstian responses from 10−6 to 10−2 mol L−1 with detection limit of 8 × 10−7 mol L−1, fast response time (1.6 s) and adequate shelf-life (6 months). Improved selectivity towards BuCh with minimal interference from choline (Ch) was achieved and the sensor was used for determination of 0.06-1.25 U mL−1 BuChE. The developed disposable sensors have been successfully applied for real-time intoxication monitoring through assaying cholinesterases (ChEs) activity in human serum. Determination of organophosphate pesticide was conducted by measuring their inhibition of BuChE with successful assaying of malathion in insecticide samples with high accuracy and precision. 相似文献
83.
New hybrid chemometric method has been applied to the emission response data. It deals with convolution of emission data using 8-points sin xi polynomials (discrete Fourier functions) after the derivative treatment of these emission data. This new application was used for the simultaneous determination of Fexofenadine and Montelukast in bulk and pharmaceutical preparation. It was found beneficial in the resolution of partially overlapping emission spectra of this mixture. The application of this chemometric method was found beneficial in eliminating different types of interferences common in spectrofluorimetry such as overlapping emission spectra and self- quenching. Not only this chemometric approache was applied to the emission data but also the obtained data were subjected to non-parametric linear regression analysis (Theil’s method). The presented work compares the application of Theil’s method in handling the response data, with the least-squares parametric regression method, which is considered the de facto standard method used for regression. So this work combines the advantages of derivative and convolution using discrete Fourier function together with the reliability and efficacy of the non-parametric analysis of data. Theil’s method was found to be superior to the method of least squares as it could effectively circumvent any outlier data points. 相似文献
84.
Novel Quinazoline Derivatives Bearing a Sulfapyridine Moiety as Anticancer and Radiosensitizing Agents
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Mostafa M. Ghorab Fatma A. Ragab Helmi I. Heiba Ahmad A. Bayomi 《Journal of heterocyclic chemistry》2014,51(Z1):E255-E262
Quinazoline derivatives posses many types of biological activities and have recently been reported to show substantial antitumor activity in vitro and/or in vivo. There is a variety of mechanisms for their anticancer activity. The present work reports the possible utility of methyl anthranilate in the synthesis of some new quinazoline derivatives, bearing a substituted sulfonamide moiety. All the newly synthesized compounds were evaluated for their in vitro anticancer activity against human liver cancer cell line, using doxorubicin as a reference drug. In addition, the most active compounds 14 and 15 were selected and evaluated for their ability to enhance the cell killing effect of γ‐radiation. 相似文献
85.
Quicksort on the fly returns the input of n reals in increasing natural order during the sorting process. Correctly normalized the running time up to returning the l-th smallest out of n seen as a process in l converges weakly to a limiting process with path in the space of cadlag functions. 相似文献
86.
Mohamed G. Assy Mohamed H. Sherif Abd El‐Galil E. Amr Osama I. Abdelsalam Mohamed A. Al‐Omar Mohamed M. Abdalla Islam Ragab 《Journal of heterocyclic chemistry》2013,50(4):766-773
In continuation of our previous work, a series of novel thiophene derivatives 4 , 5 , 6 , 8 , 9 , 9a , 9b , 9c , 9d , 9e , 10 , 10a , 10b , 10c , 10d , 10e , 11 , 12 , 13 , 14 , 15 , 16 were synthesized by the reaction of ethyl 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carboxylate ( 1 ) or 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile ( 2 ) with different organic reagents. Fusion of 1 with ethylcyanoacetate or maleic anhydride afforded the corresponding thienooxazinone derivative 4 and N‐thienylmalimide derivative 5 , respectively. Acylation of 1 with chloroacetylchloride afforded the amide 6 , which was cyclized with ammonium thiocyanate to give the corresponding N‐theinylthiazole derivative 8 . On the other hand, reaction of 1 with substituted aroylisothiocyanate derivatives gave the corresponding thiourea derivatives 9a , 9b , 9c , 9d , 9e , which were cyclized by the action of sodium ethoxide to afford the corresponding N‐substituted thiopyrimidine derivatives 10a , 10b , 10c , 10d , 10e . Condensation of 2 with acid anhydrides in refluxing acetic acid afforded the corresponding imide carbonitrile derivatives 11 , 12 , 13 . Similarly, condensation of 1 with the previous acid anhydride yielded the corresponding imide ethyl ester derivatives 14 , 15 , 16 , respectively. The structures of newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR, MS spectral data, and elemental analysis. The detailed synthesis, spectroscopic data, LD50, and pharmacological activities of the synthesized compounds are reported. 相似文献
87.
A novel group of 6-iodoquinazolin-4(3H)-one derivatives was prepared starting from 6-iodo-2-ethoxy-4H-3,1-benzoxazin-4-one (3) via action of various nitrogen nucleophiles such as primary and secondary amines, hydrazine hydrate, and its derivatives. The 3-amino-2-hydrazinyl-6-iodoquinazolin-4(3H)-one (15) was used as a key starting material to prepare new heterocyclic compounds. The structures of all synthesized compounds were inferred from the infrared, mass spectral, and 1H NMR spectral data as well as elemental analysis. The fungicidal activities of the target compounds were preliminarily evaluated. 相似文献
88.
Ragab M. Gad 《General Relativity and Gravitation》2006,38(3):417-424
We obtain the energy and momentum densities of a general static axially symmetric vacuum space-time, the Weyl metric, with the help of Landau – Lifshitz and Bergmann – Thomson energy-momentum complexes. We find that these two definitions of energy-momentum complexes do not provide the same energy density for the space-time under consideration, while give the same momentum density. We show that, in the case of the Curzon metric (a particular case of the Weyl metric), these two definitions give the same energy only when R → ∞. Furthermore, we compare these results with those obtained using Einstein, Papapetrou and MØller energy momentum complexes. 相似文献
89.
F. M. Ragab 《Annali di Matematica Pura ed Applicata》1965,69(1):35-40
Summary Infinite series of products of generalized hypergeometric functions will be established. 相似文献
90.
Different glass samples in the Li2O, PbO and B2O3 system have been prepared by melt quenching method. These glasses were classified in two groups such as 0.5 B2O3, (0.5 ? x) PbO, xLi2O and (0.5 + y) B2O3; (0.25 ? y)PbO; 0.25Li2O. The IR spectra almost show broad bands in the frequency range (800–1050) cm?1 and (1100–1500) cm?1, together with different weak bands over the range of investigation (2400–3000) cm?1. The deconvolution analyses of these IR spectra reveals presence of multi structure arrangements from BO4 and BO3 groups, such as penta, tri, and diborates grouping together with meta; ortho borates as well as PbOn groups. Partial replacement of PbO by Li2O causes decrease in microhardness, a change which is attributed to the decrease in the concentration of ortho borate groups as is it revealed from the bands area analysis. The IR analysis shows also that the total concentration of (meta + ortho) borates is nearly constant while their individual concentrations is proportional depending on the relative concentration of PbO and Li2O. 相似文献