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排序方式: 共有341条查询结果,搜索用时 15 毫秒
51.
Ali Moustafa R. K. Wu Yue Chapman Savita Ding Yong 《Research on Chemical Intermediates》2019,45(8):3973-3983
Research on Chemical Intermediates - Anisotropic nanoparticles, such as rods or bones, exhibit new properties due to their specific geometries. The development of unique properties on the surface... 相似文献
52.
Moustafa A. H. El-Sayed H. A. El Rayes S. M. Morsy H. A. Abd-allah S. H. Ismail H. F. Abd El-Aal M. M. 《Russian Journal of General Chemistry》2019,89(11):2314-2320
New pyrazole and pyridine derivatives have been synthesized from sulfanilamide and phenazone via diazotization and coupling with a wide range of α-CH acids followed by heterocyclization with hydrazine derivative, hydroxylamine and cyanoacetamide. The antimicrobial tests of the products demonstrate high to moderate activity against Gram (?ve) bacteria and the tested fungi. No positive action of the products is observed against Gram (+ve) bacteria.
相似文献53.
54.
Morsy H. A. Mohammed S. M. Abdel Hamid A. M. Moustafa A. H. El-Sayed H. A. 《Russian Journal of Organic Chemistry》2020,56(1):143-147
Russian Journal of Organic Chemistry - A facile synthesis of a new series of 1,2,3-triazolyl nucleosides via one-pot click reaction is described. Acetylenic nicotinonitriles synthesized previously... 相似文献
55.
Design,Synthesis, and Antifungal Activity of Some New Thiazolo[4,5-d]pyrimidine-5-thione Derivatives
Ghoneim A. A. Bilel H. Moustafa S. M. N. 《Russian Journal of Organic Chemistry》2020,56(12):2148-2152
Russian Journal of Organic Chemistry - A new series of thiazolo[4,5-d]pyrimidine-5-thione derivatives having indole and phenyl moieties were synthesized. Their structures were established by... 相似文献
56.
Bassam Abbas Yousef T. Salman Moustafa S. El-Daher 《Journal of Macromolecular Science: Physics》2015,54(12):1457-1465
Photoinduced birefringence in poly(methyl methacrylate) (PMMA), polymeric thin films doped with di-azo Sudan G was investigated. A pump-probe method was used to study the dynamic behavior of the birefringence. The mechanism for the inducement of birefringence is discussed in terms of the photoisomerization of the di-azo Sudan G molecules. The results showed that the dynamic evolution of the photoinduced birefringence was such that the average birefringence increased, saturated, and then decreased with respect to the laser pump intensity. Also, an exponential-like relationship was observed between both the saturation and the isotropic states of the averaged transmitted probe beam (expressing the residual anisotropy) and the birefringence on one hand, and the intensity amplitudes of the pumping powers on the other hand. 相似文献
57.
2-Aminothiophene 3 was achieved through the one-pot multicomponent reaction of cycloheptanone, cyanoacetamide, elemental sulfur, and morpholine in ethanol. Diazotization of 2-aminothiophene 3 with NaNO2/HCl gave the corresponding diazonium salt 4 , that combined with the appropriate active methylene components; 5a , 5b , 7 , 11 , 13 , 16 , 18 , 21 , 9 , 19 , 22a , and 22b in pyridine (AcONa/EtOH) to form the corresponding hydrazones 6a , 6b , 8 , 10 , 14 , 15 , 17 , 20 , 23 , 24 , 25a , and 25b , respectively. Heating of compound 8 with malononitrile 9 in ethanol gave the thiazole 10 . Treatment of compound 10 , 25a , and 25b with hydrazine hydrate achieve the pyrazoles 12 , 27a , and 27b , respectively. Hydrazinolysis of compound 14 with hydrazine hydrate, followed by condensation of the obtained hydrazide 15 with acetylacetone 19 gave the pyrazole 20 . The recently orchestrated thiophenes were assessed for their cytotoxic action. The result revealed that compound 12 indicated comparable and better action towards HePG2, HCT-116, MCF-7, and PC3 cancer cell lines than Doxorubicin. 相似文献
58.
Dina Moustafa Chelsea Sweet Hyun Lim Brenda Calalpa Parminder Kaur 《Tetrahedron letters》2018,59(42):3816-3820
A direct and efficient synthesis of arylketones via arylboronic acid addition to nitriles in presence of inexpensive Mn/Cu catalytic system is reported. The use of non-precious Mn and Cu salts has been found to be highly advantageous both in terms of accessibility as well as cost effectiveness. A series of arylboronic acids as well as nitriles were used to synthesize a variety of symmetrical and unsymmetrical arylketones. Based on the literature studies, the reaction mechanism is anticipated to go through an aryl radical intermediate which reacted with the copper activated nitrile to give the desired arylketones after the hydrolysis of the imine intermediate. 相似文献
59.
Lipase‐Catalyzed Dynamic Kinetic Resolution of C1‐ and C2‐Symmetric Racemic Axially Chiral 2,2′‐Dihydroxy‐1,1′‐biaryls 下载免费PDF全文
Dr. Gamal A. I. Moustafa Yasuhiro Oki Prof. Dr. Shuji Akai 《Angewandte Chemie (International ed. in English)》2018,57(32):10278-10282
We have discovered that the racemization of configurationally stable, axially chiral 2,2′‐dihydroxy‐1,1′‐biaryls proceeds with a catalytic amount of a cyclopentadienylruthenium(II) complex at 35–50 °C. Combining this racemization procedure with lipase‐catalyzed kinetic resolution led to the first lipase/metal‐integrated dynamic kinetic resolution of racemic axially chiral biaryl compounds. The method was applied to the synthesis of various enantio‐enriched C1‐ and C2‐symmetric biaryl diols in yields of up to 98 % and enantiomeric excesses of up to 98 %, which paves the way for new developments in the field of asymmetric synthesis. 相似文献
60.
Moustafa NE 《Journal of chromatographic science》2008,46(5):388-391
A method is developed for the analysis of associated condensate by capillary gas chromatography (GC) with simultaneous determination of its major physical characteristic parameters. The method aims at the qualitative and quantitative determination of C(2)-C(36) alkanes, methylcyclopentane, cyclohexane, methylcyclohexane, benzene, toluene, ethylbenzene, xylenes, and 1,2,4-trimethylbenzene. This composition is according to the petroleum companies demand. The method is used for the simultaneous determination of the condensate average molecular weight, density, carbon-to-hydrogen ratio, and boiling range. The data obtained by the method has a good agreement with those obtained by other methods. The literature methods cited later used a simulated distillation method to obtain the hydrocarbon distribution spectrum of the given condensate sample. The obtained results revealed that the GC capillary method used is most rapid and accurate for achieving the demanded analytical report. 相似文献