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121.
L-Sorbose 1 was converted to 5-hydroxymethylfurfural 8 in choline chloride melts in moderate yields. A simplified synthesis of sorbosylurea tetraacetate 4 in two steps using urea melts was performed, achieving good yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
122.
Javad Azizian Ali Ramazani Mohammad Haji 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):326-333
Abstract The Passerini reaction of α-ketophosphonates, isocyanides, and benzoic acid derivatives leads to 1-(N-alkylcarbamoyl)-1-(diethoxyphosphoryl)alkyl benzoates in one step at room temperature. The structures of products were assigned on the basis of their 1H NMR, 13C NMR, 31P NMR, and IR spectroscopic data. GRAPHICAL ABSTRACT 相似文献
123.
Farid Shakerian Shayessteh Dadfarnia Ali Mohammad Haji Shabani 《Journal of the Iranian Chemical Society》2013,10(4):669-676
In this study, an ion imprinted polymer (IIP) was prepared for the selective separation and preconcentration of trace levels of aluminum. Al(III) IIP was synthesized in the presence of Al(III)-8-hydroxyquinoline (oxine) complex using styrene and ethylene glycol dimethacrylate as a monomer and crosslinker, respectively. The imprinted Al(III) ions were completely removed by leaching the IIP with HCl (50 % v/v) and were characterized by FTIR and scanning electron microscopy. The maximum sorption capacity for Al(III) ions was found to be 3.1 mg g?1 at pH 6.0. Variables affecting the IIP solid phase extraction were optimized by the univariable method. Under the optimized conditions, a sample volume of 400 mL resulted in an enhancement factor of 194. The detection limit (defined as 3 S b/m) was found to be 1.6 μg L?1. The method was successfully applied to the determination of aluminum in natural water, fruit juice and cow milk samples. 相似文献
124.
Zhan-Xing Hu Hong-Yu Tang Jie Guo Haji Aker Aisa Yu Zhang Xiao-Jiang Hao 《Tetrahedron》2019,75(12):1711-1716
Stemtuberlines A (1) and B (2), two new alkaloids with a unique tricyclic pyrrolo [3,2,1-jk]benzazepine-12-one nucleus, three new croomine-type alkaloids, stemtuberlines C-E (3–5), together with seven known ones were isolated from the roots of Stemona tuberosa. The structures of the new alkaloids were elucidated based on a comprehensive spectroscopic data analysis. The absolute configurations of 1 and 2 were determined by quantum ECD calculations. The anti-tobacco mosaic virus activity of the Stemona alkaloids was firstly evaluated and compound 11 exhibited significant anti-tobacco mosaic virus activity with the curative inhibition rate of 84.6% at concentration of 50?μg/mL. 相似文献
125.
Farid Shakerian Shayessteh Dadfarnia Ali Mohammad Haji Shabani Golnaz Shiralian Esfahani 《Mikrochimica acta》2013,180(13-14):1225-1232
We have developed a method for the microextraction of lead(II) ion. It is based on the use of suspended zirconia nanoparticles modified with the reagent cadion. Pb(II) ions in the sample are adsorbed onto the modified zirconia nanoparticles suspended in the solution of a non-ionic surfactant. After cloud formation and phase separation by sedimentation, the surfactant rich phase was acidified and diluted to 100 μL with 3.0 mol L?1 nitric acid and ultrasonicated for a few seconds to desorb the analyte from the sorbent. The mixture was centrifuged and 10 μL of the supernatant liquid phase along with 10 μL of the Pd/Mg modifier were submitted to the electrothermal atomic absorption spectrometer. The parameters affecting the extraction efficiency were optimized by the univariable method. Under the optimized conditions, a sample volume of 40 mL resulted in an enhancement factor of 384 and a detection limit (defined as 3Sb/m) of 2.2 ng L?1. The method was successfully applied to the determination of Pb(II) in water, tea and rice samples. Accuracy was determined by the recovery experiments and the analysis of two certified reference materials. Figure
A new microextraction method for lead (II) is developed. It is based on the use of suspended zirconia nanoparticles modified with the reagent cadion. The method was successfully applied to the determination of the Pb(II) in water, tea and rice samples. Accuracy was determined by the recovery experiments and the analysis of two certified reference materials. 相似文献
126.
M. Kazeraninejad A. M. Haji Shabani S. Dadfarnia S. H. Ahmadi 《Journal of Analytical Chemistry》2011,66(4):373-377
A simple and reliable method has been developed for the determination of uranium(VI). The method is based on the separation
and preconcentration of uranium(VI) using a column packed with 8-hydroxyquinoline immobilized on surfactant coated alumina
prior to its spectrophotometric determination with arsenazo III. The effect of pH, sample flow rate and volume, elution conditions,
and foreign ions on the sorption of uranium(VI) has been investigated. A preconcentration factor of 200 was achieved by passing
1000 mL of sample through the column. The relative standard deviation for 10 replicate analyses at the 100 ng/mL level of
uranium(VI) was 2.1% and the detection limit was 0.12 ng/mL. The method was success-fully applied to the determination of
uranium in natural water samples. The accuracy was assessed through recovery experiments and the analysis of a certified reference
material. 相似文献
127.
M. Kazeraninejad A. M. Haji Shabani S. Dadfarnia S. H. Ahmadi 《Journal of Analytical Chemistry》2011,66(1):11-15
A simple and reliable method has been developed for the determination of uranium(VI). The method is based on the separation
and preconcentration of uranium(VI) using a column packed with 8-hydroxyquinoline immobilized on surfactant coated alumina
prior to its spectrophotometry determination with Arsenazo III. The effect of pH, sample flow rate and volume, elution conditions,
and foreign ions on the sorption of uranium(VI) has been investigated. A preconcentration factor of 200 was achieved by passing
1000 mL of sample through the column. The relative standard deviation for 10 replicate analyses at the 100 ng/mL level of
uranium(VI) was 2.1% and the detection limit was 0.12 ng/mL. The method was successfully applied to the determination of uranium
in natural water samples. The accuracy was assessed through recovery experiments and the analysis of a certified reference
material. 相似文献
128.
Tong Lu Lifei Nie Dan Tang Khurshed Bozorov Jiangyu Zhao Haji Akber Aisa 《Journal of heterocyclic chemistry》2024,61(4):651-668
Our research team has synthesized 33 tricyclic pyrazolopyrimidine arylidene ester derivatives using the lead compound CAM551 as a starting point. This was achieved by a designed five-step synthesis strategy. The synthesized compounds' inhibitory activities against HT-116 human colorectal adenocarcinoma cell line and HGC27 human gastric cancer cells were assessed through traditional MTT assays. The designed and synthesized compounds demonstrated superior inhibition against both types of cancer cells. Additionally, compound 7b , which contains a long-chain substituent, exhibited improved inhibition against hepatocellular carcinoma cells and a greater safety profile. These findings indicate that compound 7b has the potential as an antitumor lead compound for future research. 相似文献
129.
Amir Babaei Mohammad Mehdi Khorasani Mehdi Haji Abdolrasouli 《Journal of Macromolecular Science: Physics》2014,53(5):829-847
A new method to prepare single-polymer high-density (HDPE)-ultra high molecular weight polyethylene (UHMWPE) fiber (PE-PE homocomposites) composed and also PE-PE homocomposites containing HDPE organo montmorillonite clay (OMMT) nanocomposites as a matrix (PE nanohomocomposites) was used. Owing to the major importance of fiber impregnation by the matrix and its effect on the adhesion of matrix/fiber and, consequently, the mechanical properties of the composite, a combination of powder impregnation and film stacking methods, utilizing compression molding, were used for manufacturing the PE-PE homocomposites and PE nanohomocomposites. In addition, PE nanohomocomposites with the matrix containing different amounts of nanoclay were prepared to investigate the effect of the clay on the interfacial and mechanical properties of the PE-PE nanohomocomposites. Several different processing conditions were examined to determine the best conditions for manufacturing of the PE-PE homocomposite and PE nanohomocomposites and it was concluded that 40 bar and 10 min of compression molding resulted in the highest overall mechanical properties. The PE-PE homocomposites and PE-PE nanohomocomposites showed identical trends for the relationship between the effects of processing conditions and mechanical properties. Mechanical results demonstrated that clay platelets could increase the interfacial strength by improving physical entanglements between fiber and matrix through better cocrystallization. 相似文献
130.
Yili Abulimiti Yimamu Hurxid Ghulameden Saideiahmat Qing Zhao Hai Aisa Haji A. Morlock Gertrud E. 《平面色谱法杂志一现代薄层色谱法》2014,27(1):11-18
JPC – Journal of Planar Chromatography – Modern TLC - The seeds of Ocimum basilicum have traditionally been used for the prevention and treatment of a number of diseases in Xinjiang of... 相似文献