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81.
Ismail Warad Maha Al-Ali Belkheir Hammouti Taibi Ben Hadda Rami Shareiah Mohamed Rzaigui 《Research on Chemical Intermediates》2013,39(6):2451-2461
A novel di-μ-chloro-bis[chloro(4,7-dimethyl-1,10-phenanthroline)cadmium(II)] dimer complex has been prepared by reacting CdCl2·2.5H2O with 4,7-dimethyl-1,10-phenanthroline (dmphen) ligand. The complex was characterized on the basis of elemental analysis, FAB-MS, IR, UV–visible, 1H, and 13C NMR spectroscopy, TG/DTA, and X-ray single-crystal diffraction studies. The Cd(II) ions in [CdCl2(C14H12N2)]2 are coordinated to three Cl atoms with the centrosymmetric dimer bridged through the Cl atoms and two N atoms in a slightly distorted square-pyramidal disposition. Several hydrogen bonds formed between the terminal Cl atoms and H-Me/H-Ph groups may stabilize the structure in the dimer form. 相似文献
82.
83.
Hatem A. Abuelizz Mohamed Marzouk Ahmed H. Bakheit Hanem M. Awad Maha M. Soltan Ahmed M. Naglah Rashad Al-Salahi 《Molecules (Basel, Switzerland)》2020,25(24)
A series of 3-ethyl(methyl)-2-thioxo-2,3-dihydrobenzo[g]quinazolines (1–17) were synthesized, characterized, and evaluated in vitro for their antiangiogenesis VEGFR-2-targeting, antiproliferative, and antiapoptotic activities against breast MCF-7 and liver HepG2 cells. Flow cytometry was used to determine cancer-cell cycle distributions, and apoptosis was detected using annexin-V-FITC (V) and propidium iodide (PI) dyes. Fluorescence microscopy, in combination with Hoechst staining was used to detect DNA fragmentation. Most of the tested benzo[g]quinazolines demonstrated promising activity (IC50 = 8.8 ± 0.5–10.9 ± 0.9 μM) and (IC50 = 26.0 ± 2.5–40.4 ± 4.1 μM) against MCF-7 and HepG2, respectively. Doxorubicin was used as a reference drug. Compounds 13–15 showed the highest activity against both cancer cell lines. Differential effects were detected by cell-cycle analysis, indicating similarities in the actions of 13 and 14 against both MCF7 and HepG2, involving the targeting of G1 and S phases, respectively. Compound 15 showed similar indices against both cells, indicating that its cytotoxicity toward the examined cancer cells could be unselective. Interestingly, 14 and 15 showed the highest apoptosis (30.76% and 25.30%, respectively) against MCF-7. The DNA fragmentation results agreed well with the apoptosis detected by flow cytometry. In terms of antiangiogenesis activity, as derived from VEGFR-2 inhibition, 13 and 15 were comparable to sorafenib and effected 1.5- and 1.4-fold inhibition relative to the standard sorafenib. A docking study was conducted to investigate the interaction between the synthesized benzo[g]quinazolines and the ATP-binding site within the catalytic domain of VEGFR-2. 相似文献
84.
Ahmed H. Shamroukh Aymn E. Rashad Hatem S. Ali Farouk M. E. Abdel‐Megeid 《Journal of heterocyclic chemistry》2013,50(4):758-765
Novel β‐enaminonitrile of 1‐(6‐phenyl‐pyridazin‐3‐yl)‐pyrazole derivative 2 was formed using (6‐phenyl‐pyridazin‐3‐yl)‐hydrazine ( 1 ) and 2‐ethoxymethylene‐malononitrile. The β‐enaminonitrile derivative 2 was in turn used as precursors for the preparation of 1‐(6‐phenyl‐pyridazin‐3‐yl)‐pyrazoles ( 3 , 9 , 11 ), 1‐(6‐phenyl ‐pyridazin‐3‐yl)‐pyrazolo[3,4‐d]pyrimidines ( 4 , 5 , 6 , 7 , 8 , 13 , 14 , 15 , 16 ) and some of their corresponding N‐acyclic nucleosides ( 17 , 18 ). All synthesized compounds were tested for their antimicrobial evaluation, and compounds 3 , 9 , 17 , and 18 showed more significant activity than the other tested compounds and some known drugs (standers). 相似文献
85.
Hatem ElloumiMongi Stambouli Jean Jacques DamelincourtBrahim Mrabet 《Journal of Quantitative Spectroscopy & Radiative Transfer》2002,74(6):731-744
In this paper, we present the detail calculations of the indirect spectral irradiance E(λ) as a function of the spectral radiant flux Φt(λ) of a radiating source. This relation is used to predict the integrating cylinder irradiance for a given input radiant flux as a function of the geometrical parameters and reflectivity called “multiplier constant”. The radiation transfer within a cylindrical enclosure composed of three different surfaces, the inside circular surface and the two bases in the ends, has been examined. The configuration factor is introduced. Then all the configuration factors needed for our calculation have been given in analytical form. 相似文献
86.
87.
In this paper, we establish new versions of Hardy's and Miyachi's theorems for the Bessel–Struve transform. 相似文献
88.
89.
Hatem M. Bahig Ken Nakamula 《Journal of Algorithms in Cognition, Informatics and Logic》2002,42(2):304
Let ℓ(n) be the smallest possible length of addition chains for a positive integer n. Then Scholz conjectured that ℓ(2n − 1) ≤ n + ℓ(n) − 1, which still remains open. It is known that the Scholz conjecture is true when ν(n) ≤ 4, where ν(n) is the number of 1's in the binary representation of n. In this paper, we give some properties of nonstar steps in addition chains and prove that the Scholz conjecture is true for infinitely many new integers including the case where ν(n) = 5. 相似文献
90.
François Nicot Nejib Hadda Luc Sibille Farhang Radjai Pierre-Yves Hicher Félix Darve 《Comptes Rendus Mecanique》2014,342(3):174-188
This paper discusses the notion of failure in a granular assembly by examining the key microstructural mechanisms which are most likely to trigger the nucleation and propagation of instabilities within a granular material. For this purpose, the key variable to predict the occurrence of failure, known as second-order work, is expressed from variables on the grain scale. The local behaviour incidents (where contacts may open or slide), compared to the global response of the assembly, are analysed by two approaches. First, numerical computations made by a discrete element model confirm the microscopic definition of the second-order work. Secondly, a micromechanical model, based on a homogenization procedure, relating the macroscopic behaviour to microscopic ingredients, namely contact planes, points to a close link between the occurrence of failure on the macroscopic scale as well as on the contact planes. 相似文献