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671.
Maher Kammoun Imed Koubaa Yassine Ben Ali Raoudha Jarraya Youssef Gargouri Mohamed Damak Sofiane Bezzine 《Applied biochemistry and biotechnology》2010,162(3):662-670
The aim of the present work was to evaluate the anti-inflammatory properties of Cynara cardunculus L. (Asteraceae) during its growth using various solvents such as n-hexane, dichloromethane, acetone, and methanol for air-dried leaves and stems. The anti-inflammatory activities of crude
extracts were evaluated by measuring the inhibition potency of mammalian non-pancreatic phospholipases A2 (hG-IIA). The methanol
and acetone extracts of leaves harvested in February exhibit potent inhibition of hG-IIA (IC50 = 50 and 70 μg/ml, respectively). However, the acetone extract of stems harvested in December inhibits the hG-IIA with a
lower IC50 around 130 μg/ml. Fractionation on silica gel and hydrophobic gel of the methanol extract of leaves harvested in February
increases the inhibitory effect, and the IC50 reached 10 μg/ml. 相似文献
672.
Maher Berzig 《Journal of Fixed Point Theory and Applications》2012,12(1-2):221-238
In this paper, we establish coincidence and common fixed point theorems for contractive mappings on a metric space endowed with an amorphous binary relation. The presented theorems extend the results of Samet and Turinici in [Commun. Math. Anal. 12 (2012), 82– 97] and generalize many existing results on metric and ordered metric spaces. We apply also our main results to derive coincidence and common fixed point theorems for cyclic contractive mappings. 相似文献
673.
Mohamed G. El-Banna Maher A. El-Hashash Abeer M. Elnaggar Azza A. El-Badawy Sameh A. Rizk 《Journal of heterocyclic chemistry》2021,58(7):1502-1514
In the present work, reaction of 3-nitrophthalic anhydride with anthranilic acid to afford the corresponding anthranil that is treated with acetic anhydride that yielded the 2-benzoxazinonyl-5-nitrobenzoic acid (BNBA) could be isomerized to the stereogenic 9-nitrobenzoxazinone[2,3-a]isoindolinone acetate (NBIA) via basic reaction conditions. A reaction of the BNBA→NBIA was allowed with series of nitrogen nucleophiles such as formamide and hydrazine derivatives, for example, hydrazine hydrate, hydroxyl amine, acetic hydrazide, thiosemicarbazide, thiocarboihydrazide, and some amino acid, for example, glycine, alanine, and some aliphatic amine, for example, octyl amine, decyl amine, and aromatic amine, for example, aniline, o-toluidine, 4-aminobenzoic acid, and carbon nucleophiles such as malononitrile and diethylmalonate. The basicity of previous nucleophiles and thermal stability of the products can be controlled on the course of reaction. The chemical structure of the synthesized compounds can be confirmed by micro-analytical, spectral data, and they are optimized by quantum chemical parameters (DFT study) to identify the thermal stability of the products. The data obtained from the molecular modeling were correlated with those obtained from the biological screening. A novel sequence of quinazoline derivatives were synthesized, evaluated for their algaecides activity against compounds 1 , 2b , and 6 that showed the highest algaecides activities of this series with relatively low toxicity in the median lethal dose test. The obtained results proved that the most active compounds could be useful models for future design, adaptation, and investigation to construct more active analogs. 相似文献
674.
Dhahri Maher Nekoonam Saeed Hana Aouinet El Haj Assad Mamdouh Arıcı Müslüm Sharifpur Mohsen Sammouda Habib 《Journal of Thermal Analysis and Calorimetry》2021,145(3):1137-1149
Journal of Thermal Analysis and Calorimetry - This paper aims to compare the thermal performance of four different configurations of absorber wall for the solar chimney-shaped channels. A detailed... 相似文献
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Indole-2,3-dione ( 1 ) was treated with malonic acid ( 2 ) in a mixture of ethanol/pyridine to afford 1-[3-(2-oxoindolinylidene)]acetic acid ( 3 ). Compound 3 reacted with thionyl chloride to give the corresponding acid chloride ( 4 ). The acid chloride 4 reacted with arenes in the presence of AlCl3 to yield 3-(2-oxoindolinylidene)acetophenones 5a–c . Compounds 5a–c reacted with 3-methylpyrazolin-5-one derivatives 6a , b to give 3-aracyl-3-[4′-(3′-methylpyrazolin-5-onyl)]-indoline-2-one derivatives 7a–f . Compounds 7a–f were treated with phosphorus pentoxide in phosphoric acid, with ammonium acetate or methanolic methylamine and with phosphorus pentasulfide to give spiro[indoline-3,4′-(pyrazolo[4,5-b]pyran)]-2-ones 8a–f , spiro[indoline-3,4′-(pyrazolo[4,5-b]-dihydropyridine)]-2-ones 9a–f , 10a–f and spiro[indoline-3,4′-(pyrazolo[4,5-b]thiopyran)]-2-ones 10a–f , respectively. All of the synthesized spiroheterocycle derivatives were identified by conventional spectroscopic methods (IR, 1H NMR) and elemental analyses. © John Wiley & Sons, Inc. 相似文献