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61.
M. A. Abdou 《Nonlinear dynamics》2008,52(3):277-288
The improved F-expansion method with a computerized symbolic computation is used to construct the exact traveling wave solutions
of four nonlinear evolution equations in physics. As a result, many exact traveling wave solutions are obtained which include
new soliton-like solutions, trigonometric function solutions, and rational solutions. The method is straightforward and concise,
and it holds promise for many applications. 相似文献
62.
M. A. Abdou 《Nonlinear dynamics》2008,52(1-2):95-102
In this paper, a generalized auxiliary equation method with the aid of the computer symbolic computation system Maple is proposed to construct more exact solutions of nonlinear evolution equations, namely, the higher-order nonlinear Schrödinger equation, the Whitham–Broer–Kaup system, and the generalized Zakharov equations. As a result, some new types of exact travelling wave solutions are obtained, including soliton-like solutions, trigonometric function solutions, exponential solutions, and rational solutions. The method is straightforward and concise, and its applications are promising. 相似文献
63.
In this paper, with the aid of computer symbolic computation system such as Maple, an algebraic method is firstly applied
to two nonlinear evolution equations, namely, nonlinear Schrodinger equation and Pochhammer–Chree (PC) equation. As a consequence,
some new types of exact traveling wave solutions are obtained, which include bell and kink profile solitary wave solutions,
triangular periodic wave solutions, and singular solutions. The method is straightforward and concise, and it can also be
applied to other nonlinear evolution equations in mathematical physics. 相似文献
64.
M. A. Abdou 《Nonlinear dynamics》2008,52(1-2):129-136
In this paper, an extended tanh method with computerized symbolic computation is used for constructing the traveling wave
solutions of coupled nonlinear equations arising in physics. The obtained solutions include solitons, kinks, and plane periodic
solutions. The applied method will be used in further works to establish more entirely new solutions for other kinds of nonlinear
evolution equations arising in physics. 相似文献
65.
Abdou O. Abdelhamid Sobhi M. Gomha Waleed A. M. A. El‐Enany 《Journal of heterocyclic chemistry》2019,56(9):2487-2493
Sodium salt of 3‐hydroxy‐1‐(1‐aryl‐5‐methylpyrazolyl)propenone derivatives was used as a precursor for synthesis of various fused azolopyrimidine ring systems as pyrazolopyrimidines, triazolopyrimidines, and pyrimidobenzimidazoles following many procedures. The identity of the prepared compounds was elucidated by their spectral data and elemental analyses. The in vitro antimicrobial activity of 13 new compounds was evaluated, and many derivatives showed good to moderate activity. 相似文献
66.
New antineoplastic series of substituted benzothiazolo-β-aminobisphosphonic acids have been developed on the basis of the prospecting potency of the benzothiazole motifs and the aminomethylenebisphosphonate moiety as well as on the prediction of the biological activity utilizing computer program PASS, version 2014-1. Target compounds were obtained in excellent yields (70–90%) via Phospha–Michael-type addition reaction of tetraethyl methylene-1,1-bisphosphonate reagent to a group of Schiff bases incorporating benzothiazole moiety. The reactions proceeded under microwave irradiation, utilizing the advantages of the environment, friendly protocol such as high efficiency, short reaction time, and excellent yields. In consistency with the prospected results, the new NBP acids revealed positive properties against human breast and colon tumor cell lines. Remarkable potency for six lead compounds (out of 12) was observed against breast (MCF7, MDAMB/435, MDAMB/231/ATCC, HS-578T with GI50: 2.05–6.47 μM) and colon (COLO-205, HCT-116, HCC-2998, and SW-620 with GI50: 3.03–7.92 μM) carcinoma cell lines when compared with the positive control Adriamycin (breast, GI50: 3.27–6.64 μM; colon, GI50: 4.09–8.75 μM). Notably, there is a consistency between the prediction and the determined biological results. 相似文献
67.
Mohamed Abdou Christoph Kratky Georg Uray 《Monatshefte für Chemie / Chemical Monthly》1990,121(12):1039-1043
Summary The crystal structure of (–)-diphenylethanediammonium-(R,R)-tartrate was determined. From this structure determination, the (S,S) configuration was assigned to the (–)-diphenylethanediamine. The asymmetric unit of the crystal structure contains two units of the title compound plus one molecule of ethanol and one water molecule, which form an intricate network of 19 hydrogen bonds.
Die Kristallstruktur von (S,S)-Diphenylethandiammonium-(R,R)-tartrat
Zusammenfassung Es wurde die Kristallstruktur von (–)-Diphenylethandiammonium-(R,R)-tartrat bestimmt. Aus dieser Strukturbestimmung ergab sich die Zuordnung der (S,S)-Konfiguration zum (–)-Diphenylethandiamin. Die asymmetrische Einheit der Kristallstruktur besteht aus zwei Formeleinheiten der Titelverbindung sowie einem Molekül Ethanol und einem Wassermolekül, welche ein komplexes Netzwerk von insgesamt 19 Wasserstoffbrücken bilden.相似文献
68.
3-Ethoxycarbonyl-5-methyl-1-(4-methylphenyl)-4-pyrazoloylhydroximoyl chloride (1) reacted with o-phenylenediamine, o-aminothiophenol, o-aminophenol and methyl anthranilate to afford 3-nitrosoquinoxaline, benzothiadiazine, benzoxadiazine, and 3-hydroxyquinazoline, respectively. Imidazo[1,2-a]pyridine, imidazo[1,2-a]pyrimidine and isoxazole derivatives were obtained via the reaction of 1 with 2-aminopyridine, 2-aminopyrimidine and the appropriate active methylene compounds, respectively. Pyrazolo[3,4-d]pyridazines, and pyrrolidino[3,4-d]isoxazolines derivatives were also synthesized. The structures of the newly synthesized compounds were established on the basis of spectral data and alternate synthesis whenever possible. 相似文献
69.
Hydroximoyl chlorides 3 react with acrylonitrile, N-arylmaleimide and maleic anhydride to give isoxazolines 5 , pyrrolidino[3,4-d]isoxazolines 8 , and furolidino[3,4-d]isoxazolines 9 , respectively. 3 reacted with 2-aminopyridine, 2-aminopyrimidine, o-phenylenediamine and o-aminothiophenol to yield 3-ni-trosoimidazo[1,2-α]pyridines 20 , 3-nitrosopyrimidines 22 , 3-naphthoyl-1,4-dihydrobenzo-1,2,4-triazines 24 , and 3-naphthoyl-4H-1,3,4-benzothiadiazine 27 , respectively. Compound 3 reacted with benzoylacetonitrile, acetoacetanilide, thiophenol, benzencsulfinic acid in ethanolic sodium ethoxide solution to give the corresponding isoxazoles 12–13 and oximes 16–17 , respectively. The structures of these products were confirmed by elemental analyses, spectral data and, wherever possible, alternative synthesis. 相似文献
70.
Charles H. Devillers Abdou K.D. Dimé Hélène Cattey Dominique Lucas 《Comptes Rendus Chimie》2013,16(6):540-549
A new purification method of magnesium(II) and zinc(II) porphine complexes (MgP and ZnP, respectively) by crystallization of their respective pyridine adducts is described. Pure MgP and ZnP can be regenerated by removal of the coordinated pyridine ligands by heating at 200 °C under vacuum. X-ray crystallographic structures of the pyridine adducts are presented for the first time. NMR analyses of the adducts reveal the coordination of two pyridine molecules. Electrochemical as well as UV-vis absorption spectroscopy analyses in DMF of MgP·(Py)2, ZnP·(Py)2, MgP and ZnP indicate that pyridine adducts are totally dissociated. Besides, oxidation peaks of these complexes are totally irreversible, revealing a high reactivity of the oxidized species. Electrolyses at the first oxidation potential lead to the formation of the meso-meso (ZnP)2 and (MgP)2 dimers, oligomers and polymers on the electrode surface, as attested by MALDI-TOF mass spectrometry and UV-vis absorption spectroscopy analyses of the crude solution. 相似文献