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31.
32.
Fatma El-Mariah Mona Hosny Ali Deeb 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2505-2517
A series of 3-substituted pyridazino[3′,4′:3,4]pyrazolo[5,1-c]-1,2,4-triazens have been synthesized starting from the 3-carboxylic acid derivative 2. The reaction of the acid chloride 3 with amines gave the corresponding anilides 4. The reaction of 2 with ethyl chloroformate and sodium azide in the presence of triethyl amine gave the carbonyl azide 5, which underwent a Curtius rearrangement in boiling ethanol to afford the carbamate 6, which converted to the 3-amino derivative 7 upon alkaline hydrolysis, and the reaction with acid chloride resulted in N-substituted products 9. On other hand, the reaction of the carboxylic acid 2 with POCl3 and thiosemicarbazide afforded 2-amino-1,3,4-thiadiazole derivative 13. The condensation of 13 with aldehydes furnished 14 in a good yield. The products were screened for their antimicrobial activity against six microorganisms. 相似文献
33.
Ali Deeb 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):637-650
AbstractThis review describes the synthesis and reactions of 5-aminothieno[2,3-c]pyridazine-6-carbonitriles as a building blocks for the synthesis of polyfunctionalized heterocyclic compounds. The antimicrobial activity of some compounds are discussed. 相似文献
34.
Ali Deeb Mahmoud Kotb Mohamed El-Abbasy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2245-2252
3-Substituted pyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine-2,4-di-ones and 3-amino-2-methylpyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine-4-ones were synthesized starting from ethyl 5-aminothieno[2,3-c] pyridazine-6-carboxylate 1. Reaction of amino ester 1with phenyl isothiocyanate affords thiourea derivative 10which undergo further transformation to the related fused heterocyclic systems. 相似文献
35.
Moamen S. Refat Gehad G. Mohamed Mohamed Y. S. Ibrahim Hamada M. A. Killa Hammad Fetooh 《Russian Journal of General Chemistry》2013,83(12):2479-2487
Solid complexes have been prepared and characterized by IR, UV-Vis, elemental analysis, and 1H NMR. Indomethacin forms complexes with Cd(II), Ce(III), and Th(IV) ions in molar ratios (ligand: metal) (2: 1), (3: 1), and (4: 1), respectively. The IR spectra of the complexes suggest that the Indomethacin behaves as a monobasic monodentate ligand coordinated to the metal ions via the deprotonated carboxylate group. Prepared complexes exhibit higher antimicrobial activity against several microorganisms, compared to free ligand. 相似文献
36.
Salah Abd El Wanees Sabry Hamed Seda 《Journal of Dispersion Science and Technology》2013,34(12):1813-1826
AbstractThe kinetics of H2 production during Zn corrosion in 0.5?M HCl without and with various additives of N,N'-bis-(1-hydroxyphenylimine)-2,5-thiophenedicarboxaldehyde (HPTD) was studied using gasometry and electrochemical techniques. The surface of the corroded Zn samples was investigated using SEM and Optical Profilometry. The rate of H2 production (RHP) increased with the immersion time and temperature. Presence of HPTD mitigated RHP due to an adsorption process. The electrochemical impedance spectroscopy showed that HPTD had a good inhibitive effect. Polarization data proved that HPTD acted as a surface-active mixed-type inhibitor. Some thermodynamic parameters were deduced and discussed. Theoretical calculations were also conducted to corroborate the capability of HPTD to protect Zn surface from corrosion process. 相似文献
37.
Ayman A. Gouda 《International journal of environmental analytical chemistry》2013,93(12):1210-1222
A solid phase extraction procedure has been developed using multiwalled carbon nanotubes (MWCNTs) as a solid sorbent and quinalizarin [1,2,5,8-tetrahydroxyanthracene-9,10-dione] as a chelating agent for separation and preconcentration of trace amounts of some heavy metal ions, Cd(II), Cu(II), Ni(II), Pb(II) and Zn(II) before their determination by flame atomic absorption spectroscopy (FAAS). The influences of the analytical parameters, including pH, amounts of quinalizarin and adsorbent, sample volume, elution conditions such as volume and concentration of eluent, flow rates of solution and matrix ions, were investigated for the optimum recoveries of the analyte ions. No interference effects were observed from the foreign metal ions. The preconcentration factor was 100. The detection limit (LOD) for the investigated metals at the optimal conditions were observed in the range of 0.30–0.65 μg L?1. The relative standard deviation (RSDs), and the recoveries of standard addition for this method were lower than 5.0% and 96–102%, respectively. The new procedure was successfully applied to the determination of analytes in food, water and environmental samples with satisfactory results. 相似文献
38.
《Tetrahedron letters》2014,55(51):7015-7018
Recently, we have identified the first inhibitors of Rad6B, an E2 enzyme essential for post-replication DNA repair and a potential new drug target for the treatment of breast cancer. We report two newly optimised synthetic routes to our [4-amino-6-(phenylamino)-1,3,5-triazin-2-yl]methyl 4-nitrobenzoate target compounds TZ8 and TZ9 with general applicability for further structure–activity relationship studies around this pharmacophore. The key step involved the condensation/cyclisation between phenylbiguanide and either ethyl bromoacetate or dimethyloxalate in good yield. 相似文献
39.
El-Azim M. H. M. Abd Assay M. G. Farid W. Hamid A. M. Abdel 《Russian Journal of Organic Chemistry》2022,58(4):597-603
Russian Journal of Organic Chemistry - A thiourea derivative, 4-chloro-N-[(4-chlorophenyl)carbamothioyl]benzamide, was oxidized with iodine in acetic acid to give the corresponding disulfide,... 相似文献
40.
Mohammed S. M. Moustafa A. H. El-Sayed H. A. Amin A. S. Haggar A. Tantawy E. S. Haggam R. A. 《Russian Journal of General Chemistry》2022,92(9):1806-1813
Russian Journal of General Chemistry - A highly efficient synthetic methodology for the preparation of 2-thioxocytosine was achieved by the nucleophilic addition of thiourea to... 相似文献