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271.
Design,Docking, and Synthesis of Some New Pyrazoline and Pyranopyrazole Derivatives as Anti‐inflammatory Agents
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Magda M. F. Ismail Nagy M. Khalifa Hoda H. Fahmy Eman S. Nossier Mohamed M. Abdulla 《Journal of heterocyclic chemistry》2014,51(2):450-458
Design and synthesis of some novel pyrazoline and pyranopyrazole derivatives as potential anti‐inflammatory agents are described. Most of the compounds were tested for their anti‐inflammatory (in vitro and in vivo) and ulcerogenic activities. In all tested compounds, it was found that pyrazolines, 2a , and pyrazolopyrano[2,3‐d]pyrimidine 9 are the potent anti‐inflammatory and selective cyclooxygenase‐2 (COX‐2) inhibitor. All compounds are mainly in the safe level. Docking study of 2a and 9 revealed higher affinity for binding with the active site of COX‐2 enzyme like SC‐558, a selective COX‐2 inhibitor. 相似文献
272.
Eman M. Flefel Waled A. Tantawy Randa E. Abdel-Mageid Abd El-Galil E. Amr Rolla Nadeem 《Research on Chemical Intermediates》2014,40(4):1365-1381
3-(Naphthalen-1-ylmethylene)-5-phenylfuran-2(3H)-one 1 was prepared and converted into a variety of heterocyclic systems of synthetic and biological importance. Benzylamine was reacted with furanone 1 to afford compounds 2 and 3 according to the reaction conditions. Butanamide 2 was reacted with thionyl chloride or thiourea to give derivatives 4 and 5, respectively. Compound 3 was reacted with ethyl cyanoacetate to give the corresponding pyrrolopyridine derivative 6. Treatment of 1 with hydrazine hydrate afforded compounds 7 and 8 according to the reaction conditions. Also, compound 1 was reacted with phenyl hydrazine, hydroxyl amine, malononitrile or thiourea to give compounds 9–12, respectively. Cyclization of 7 with ethoxymethylene-malononitrile, ethyl-(ethoxymethylene)cyanoacetate, carbon disulphide or acetylacetone afforded the corresponding compounds 13–16, respectively. Condensation of 7 with p-nitrobenzaldehyde gave the corresponding hydrazone 17, which was treated with thioglycolic acid or chloroacetyl chloride to give compounds 18 and 19, respectively. Also, most of the prepared products were tested for anti-avian influenza virus and revealed promising antiviral activity against H5N1 virus [A/Chicken/Egypt/1/2006 (H5N1)] by determination of both TC 50 and ED 50 and confirmed by plaque reduction assay on MDCK cells. Compounds 7, 8, 11, 12 and 13 showed the highest effect compared with the other tested compounds. 相似文献
273.
Shaaban K. Mohamed Sabry H. H. Younes Eman M. M. Abdel‐Raheem Joel T. Mague Mehmet Akkurt Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(11):959-964
The wide diversity of applications of thiosemicarbazones and bis(thiosemicarbazones) has seen them used as anticancer and antitubercular agents, and as ligands in metal complexes designed to act as site‐specific radiopharmaceuticals. Molecules of 1,1′‐({[(ethane‐1,2‐diyl)dioxy](1,2‐phenylene)}bis(methanylylidene))bis(thiosemicarbazide) {alternative name: 2,2′‐[ethane‐1,2‐diylbis(oxy)]dibenzaldehyde bis(thiosemicarbazide)}, C18H20N6O2S2, (I), lie across twofold rotation axes in the space group C2/c, with an O—C—C—O torsion angle of −59.62 (13)° and a trans‐planar arrangement of the thiosemicarbazide fragments relative to the adjacent aryl rings. The molecules of (I) are linked by N—H...S hydrogen bonds to form sheets containing R24(38) rings and two types of R22(8) ring. In the N,N‐dimethylformamide disolvate, C18H20N6O2S2·2C3H7NO, (II), the independent molecular components all lie in general positions, but one of the solvent molecules is disordered over two sets of atomic sites having occupancies of 0.839 (3) and 0.161 (3). The O—C—C—O torsion angle in the ArOCH2CH2OAr component is −75.91 (14)° and the independent thiosemicarbazide fragments both adopt a cis‐planar arrangement relative to the adjacent aryl rings. The ArOCH2CH2OAr components in (II) are linked by N—H...S hydrogen bonds to form deeply puckered sheets containing R22(8), R24(8) and two types of R22(38) rings, and which contain cavities which accommodate all of the solvent molecules in the interior of the sheets. Comparisons are made with some related compounds. 相似文献
274.
Eman S. Elzanfaly Hala E. Zaazaa Aya T. Soudi Maissa Y. Salem 《Chemical Papers》2015,69(12):1541-1547
Two validated chromatographic methods developed for the analysis of S Clopidogrel bisulphate in the presence of its related substances listed in the United States and British Pharmacopoeias including its inactive R enantiomer are described. The first method is a simple thin layer chromatographic (TLC) method where separation is performed on pre-coated silica gel 60 F254 plates using methanol/diethylamine/heptanes/water containing 20 mg vancomycin hydrochloride (7 : 7 : 1.5 : 0.5 vol. %) as a mobile phase. Rf values were found to be 0.69, 0.74, 0.78, 0.84 and 0.88 for R clopidogrel, S clopidogrel, related substances A, B1 and B2, respectively. The second method depends on the separation by HPLC on a Lux polysaccharide chiral column with UV detection at 220 nm using 0.1 vol. % diethyl amine in methanol pumped at a rate of 1 mL min?1. Retention times were found to be 1.90 min, 2.82 min, 3.00 min, 3.27 min and 3.71 min for the related substances A, B1, C which are clopidogrel R enantiomer, B2, and S clopidogrel, respectively. The proposed methods were validated in accordance with the ICH guidelines and successfully applied to the determination of S clopidogrel bisulphate in pure powder and dosage forms without interference from the excipients and to affirm the dosage form to be pure S clopidogrel and devoid of the R enantiomer, which is inactive. 相似文献
275.
Electrochemical Morphine Sensor Based on Gold Nanoparticles Metalphthalocyanine Modified Carbon Paste Electrode
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Composites of gold nanoparticles (Au) electrochemically deposited and different metal phthalocyanines (Co, Ni, Cu, and Fe) were chemically prepared. The composites were used as modifiers for carbon paste electrodes and were used for the determination of morphine in presence of ascorbic acid and uric acid. Central metal atoms of phthalocyanine moiety affected the rate of electron transfer. Thus, the electroactivity of different modifiers were evaluated towards morphine oxidation. Au‐CoPcM‐CPE possessed the highest rate for charge transfer rate in all studied pH electrolytes. Limit of detection was 5.48×10?9 mol L?1 in the range of 4.0×10?7 to 9.0×10?4 mol L?1. 相似文献
276.
Eman M. Mohi El-Deen Manal M. Anwar Sherifa M. Hasabelnaby 《Research on Chemical Intermediates》2016,42(3):1863-1883
A series of new ethyl 4-(2-(benzofuran-2-yl)-4-substituted-1,4,5,6,7,8-hexahydroquinolin-1-yl)-benzoate 3a–c was synthesized by Michael condensation of benzofuran chalcones 1a–c and cyclohexanone to give 2-(2-benzofuranyl)-4-substituted-5,6,7,8-tetrahydro-4-H -chromene 2a–c, followed by reaction of the latter with ethyl 4-aminobenzoate. Condensation of 3a–c with different amines afforded the corresponding amides 4a–e. On the other hand, upon treatment compounds 3a–c with hydrazine hydrate gave the benzohydrazide derivatives 5a–c. The reaction of compounds 5a–c with different thio/isocyanate gave the corresponding thiosemicarbazide and semicarbazide derivatives 6a–c. Meanwhile compounds 5a–c were reacted with ethyl cyanoacetate and different β-dicarbonyl compounds such as acetyl acetone, ethyl acetoacetate, and diethyl malonate to afford pyrazolyl derivatives 7a, b; 8a, b; 9a, b; and 10a–c, respectively. Moreover, 5a–c were reacted with carbon disulfide to synthesize the corresponding oxadiazolyl derivatives 11a–c, while their condensation with different aromatic aldehydes gave the corresponding Schiff bases 12a–d. Cytotoxic evaluation of some of the newly synthesized compounds against human hepatocellular carcinoma cell lines (HepG-2) revealed that the tested compounds produce promising inhibitory effect against the growth of HepG-2 cells with IC50 values ranged from 11.9 to 19.3 µg/mL. 相似文献
277.
Optical and FTIR spectroscopic measurements and electron paramagnetic resonance (EPR) properties have been utilized to investigate and characterize the given compositions of binary bismuth silicate glasses. In this work, it is aimed to study the possibility of using the prepared bismuth silicate glasses as a good shielding material for γ-rays in which adding bismuth oxide to silicate glasses causes distinguish increase in its density by an order of magnitude ranging from one to two more than mono divalent oxides. The good thermal stability and high density of the bismuth-based silicate glass encourage many studies to be undertaken to understand its radiation shielding efficiency. For this purpose a glass containing 20% bismuth oxide and 80% SiO2 was prepared using the melting–annealing technique. In addition the effects of adding some alkali heavy metal oxides to this glass, such as PbO, BaO or SrO, were also studied. EPR measurements show that the prepared glasses have good stability when exposed to γ-irradiation. The changes in the FTIR spectra due to the presence of metal oxides were referred to the different housing positions and physical properties of the respective divalent Sr2+, Ba2+ and Pb2+ ions. Calculations of optical band gap energies were presented for some selected glasses from the UV data to support the probability of using these glasses as a gamma radiation shielding material. The results showed stability of both optical and magnetic spectra of the studied glasses toward gamma irradiation, which validates their irradiation shielding behavior and suitability as the radiation shielding candidate materials. 相似文献
278.
279.
Khairia M. Al-Ahmary Moustafa M. Habeeb Eman A. Al-Solmy 《Journal of solution chemistry》2010,39(9):1264-1277
Charge transfer complex formation between 2-aminopyridine (2AP) as the electron donor with 2,5-dihydroxy-p-benzoquinone (AHBQ) as the π-electron acceptor has been investigated spectrophotometrically in acetonitrile (AN) and 50% acetonitrile + 50% 1,2-dichloroethane
(V/V), (ANDC). The stoichiometry of the complex has been identified by Job’s method to be 1:1. The Benesi-Hildebrand equation
has been applied to estimate the formation constant (K
CT) and molecular extinction coefficient (ε). It was found that the value of K
CT is larger in ANDC than in AN. The thermodynamic parameters are in agreement with the K
CT values in that the enthalpy of formation (−ΔH) has a larger value in ANDC than in AN, suggesting higher stability of the complex in ANDC. The complex formed between 2AP
and DHBQ has been isolated as a solid and characterized using elemental analysis, FTIR, and 1H NMR measurements. Moreover, it has been found that the formed complex involves proton transfer in addition to charge transfer. 相似文献
280.