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81.
SHI Lei FENG Xiu-e LIN Wen-han FANG Lian-hua DU Guan-hua LI Qing-shan . School of Pharmaceutical Science Shanxi Medical University Taiyuan P. R. China . State Key Laboratory of Natural Biomimetic Drugs Peking University Beijing 《高等学校化学研究》2011,(2):237-240
A series of new flavanone derivatives of farrerol was designed and synthesized as a potent inhibitor of vascular smooth muscle cells(VSMCs) vegetation according to a convenient method. The structures of all the synthesized compounds were confirmed by 1H NMR, 13C NMR and EIHR-MS. The biological activities of these compounds against VSMCs in vitro were evaluated. The assay results indicate that two compounds, 5,7-dihydroxy-6,8-dimethyl- 2-(2-nitrophenyl)chroman-4-one(7f) and 2,3-dibromo-4,5-dihydroxydiphenylm... 相似文献
82.
REN Lin WANG Dian SUN Gui-ting NIU Li-gang YANG Han SONG Jun-feng State Key Laboratory on Integrated Optoelectronics College of Electronic Science Engineering Jilin University Changchun P. R. China 《高等学校化学研究》2011,27(1):113-116
The present paper covers the various photonic crystals(PhCs) structures mimicking real atom-lattice structures in electronic crystals by using the femtosecond laser-induced two-photon photopolymerization of SU-8 resin. The bandgap properties were investigated by varying the crystal orientations in <111>, <110> and <100> of diamond-lattice PhCs. The photonic stop gaps were present at λ=3.88 μm in <111> direction, λ=4.01 μm in <110> direction and λ=5.30 μm in <100> direction, respectively. In addition, defect... 相似文献
83.
WEI Wei LI Xu-wen SHI Xiao-lei ZHOU Hong-yu YANG Rui-jie ZHANG Han-qi JIN Yong-ri College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2011,27(1):23-27
Matrix solid-phase dispersion(MSPD) was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots of Aconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid suppo... 相似文献
84.
The analytical expressions of the various structural units and the average degree of branching for the hyperbranched polymers resulted from AB_2 polycondensation with substitution effect were derived by the kinetic mechanism.The reactivity difference between the B group in linear unit and that in terminal group has great effect on the molecular parameters of the products obtained.The concentration of terminal units has a maximum with the increase of the conversion of A groups(x).The higher the reactivity... 相似文献
85.
86.
Hafnium(Ⅳ) bis(perfluorooctanesulfonyl)imide complex is found to be an efficient catalyst for the multicomponent condensation ofβ-naphthol,aromatic aldehydes and urea or amides in perfluorodecalin to afford the corresponding substituted amidomethyl naphthols in good yields.The remarkable features of this new procedure are high yields,shorter reaction times, reusability of catalyst and simple work-up procedures. 相似文献
87.
Hierarchical TS-1 has been synthesized in the presence of cationic organosilane surfactant.The material is characterized with XRD,TEM,N2 adsorption isotherm.The results show that the hierarchical TS-1 aggregates consist of small primary units with sizes of 20-30 nm.The BET surface area increases from 420 to 513 m2/g compared to conventional TS-1 zeolite.The sample is shown to be more active in epoxidation of cyclohexene than conventional TS-1. 相似文献
88.
This work described a sensitive method for determination of metoprolol in rabbit plasma.The method involved purification by ultrafiltration,derivatization with fluorescein isothiocyanate,determination by capillary electrophoresis(CE) coupled with laser-induced fluorescence(LIF) detector.Other components in plasma including a variety of amino acids and proteins did not interfere with the determination of metoprolol in experimental condition.The assay had a wide range(2.0-500 ng/mL) of linearity and a detection limit of 0.8 ng/mL.The intra- and inter-day precisions were satisfactory with relative standard deviation(RSD) less than 10.0%and accuracy within 10.0%.This method was successfully applied to pharmacokinetic study of metoprolol in rabbit blood. 相似文献
89.
A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3’-pyrrolo[2,3-b]pyridin]-2’(1’H)-one 1 is described.The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ring by an intramolecular Buchwald-Hartwig amidation of carboxylic ami Je and aryl chloride.A small library was obtained by reductive amination of 1 with various aldehydes and was screened against human lung cancer cell A549,human liver cancer cell BEL7402,and human colon cancer cell HCT-8.The results show that most of the 1(?)rary compounds 2 have some inhibitory activities.2-(Trifluoromethoxy) benzylic substituted spirocyclic azaoxindole 2e was identified as a nanomolar inhibitor against human lung cancer cell A-549(IC50=50 nmol/L). 相似文献
90.
A series of new ligands L1-L7 were readily prepared in one step.Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by a novel Cu(Ⅱ)-L complex has been developed.The remarkable advantages of this reaction are mild reaction conditions,simple workup procedure,high yields of products and the use of ethanol as a green solvent. 相似文献