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171.
Ten coumarin derivatives containing(E)-methyl 2-(methoxyimino)-2-phenylacetate were synthesized and bioassayed.The compounds were identified by IR,~1H NMR and elemental analyses.The test results indicated that compound 5j(R~1 is methyl and R~2 is n-C_6H_(13)) was the optimal structure in this paper with good fungicidal activity against CDM(85%) at 6.25 mg/L concentration. 相似文献
172.
Yu Ming Dong Guang Li Wang Ping Ping Jiang Ai Min Zhang Lin Yue Xiao Ming Zhang 《中国化学快报》2011,22(2):209-212
ZnO particles about 200 nm were prepared through a facile hydrothermal method.Compared with single ozonation,the degradation efficiency of phenol increased about 23.7%and the degradation efficiency of intermediates improved about four times in the presence of ZnO at 298 K.In addition,the catalyst had good stability in the ozonation process.The influence of temperature was investigated and it was found that the better catalysis efficiency could be obtained at lower temperature. 相似文献
173.
A novel high performance liquid chromatography-chemiluminescence(HPLC-CL) method for investigation of in vitro metabolism of repaglinide in pig liver microsomes with microdialysis sampling technique was developed.The chromatographic separation was performed on a Hypersil BDS-C18 column with an isocratic mobile phase consisting of methanol and 0.01 mol/L KH2PO4(pH 3.0)(volume ratio 75:25) at a flow rate of 1.0 mL/min.The detection was based on the chemiluminescence reaction of repaglinide with acidic potassium permanganate(KMnO4) and tris(2,2’-bipyridyl)ruthenium(Ⅲ)(Ru(bpy)33+),which was immobilized on the cationic ion-exchange resin for obtaining high sensitivity and reducing consumption of expensive reagent. 相似文献
174.
ZHANG Ai ZHENG ZongMin CHENG FangYi TAO ZhanLiang & CHEN Jun Key Laboratory of Advanced Energy Materials Chemistry Ministry of Education College of Chemistry Nankai University Tianjin China 《中国科学B辑(英文版)》2011,(6)
We report on the preparation of spinel Li4Ti5O12 submicrospheres and their application as anode materials of rechargeable lithium-ion batteries. The spinel Li4Ti5O12 submicrospheres are synthesized with three steps of the hydrolysis of TiCl4 to form rutile TiO2, the hydrothermal treatment of rutile TiO2 with LiOH to prepare an intermediate phase of LiTi2O4+δ, and the calcinations of LiTi2O4+δ to obtain spinel Li4Ti5O12. The as-prepared products are investigated by X-ray powder diffraction (XRD), scanning el... 相似文献
175.
An effective one-pot synthesis of quinolines bearing diverse C3-piperazinyl functions was developed by using a modified Friedl?nder's protocol. The method not only enables the synthesis of our early reported c-Met inhibitor on a large scale, but also provides a way to generate novel multi-substituted quinolines for further structure-activity relationship (SAR) study. 相似文献
176.
The development of a new class of hydrazide type organocatalyst, (4R,5R)-1,3-bis(isopropylamino)-4,5-dihenylimidazolidin-2-one 2a, for enantioselective Diels-Alder reactions between cyclopentadiene and α,β-unsaturated aldehydes are presented. The new organocatalyst 2a promoted the reaction, affording Diels-Alder adducts in good yields with good levels of enantioselectivity. 相似文献
177.
Electrospinning is known to be a highly versatile method to produce nanofibers, and several techniques have been developed
to align nanofibers. In this paper, poly(vinyl alcohol) (PVA), poly(vinylpyrrolidone) (PVP), poly(propylene carbonate) (PC),
poly(ethylene oxide) (PEO), PVA/Chitosan and PVA/Fe3O4 uniaxially aligned ultrafine fibers were obtained with electrospinning method by adding another electric field in the collection
area. Alignment of the nanofibers was characterized by the use of digital cameras and field emission scanning electron microscopy,
polarized Fourier transform infrared spectroscopy (FTIR), and wideangle X-ray diffraction (XRD). The mechanism of fiber alignment
was investigated as well. 相似文献
178.
Ogawa A Miyamae Y Honma A Koyama T Yazawa K Shigemori H 《Chemical & pharmaceutical bulletin》2011,59(5):672-675
A new compound, pycnalin (1), together with four known compounds, ginnalins A (2), B (3), C (4), and 3,6-di-O-galloyl-1,5-anhydro-D-glucitol (3,6-di-GAG) (5), were isolated from Acer pycnanthum. The structure of 1 was determined on the basis of 2D-NMR spectral data and synthesis of 1. Pycnalin (1) is the first 1,5-anhydro-D-mannitol linked to a gallic acid, while compounds 2-5 were 1,5-anhydro-D-glucitol linked to gallic acids. All compounds were tested in vitro for α-glucosidase inhibitory and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities. Pycnalin (1) exhibited moderate α-glucosidase inhibitory activity as well as free radical scavenging activity. Ginnalin A (2) and 3,6-di-GAG (5), which have two galloyl groups, exhibited potent α-glucosidase inhibition, compared to those of other compounds 1, 3, and 4 containing a galloyl group. These results suggest that α-glucosidase inhibition is influenced by the number of galloyl groups. 相似文献
179.
Yong Shen Ai‐Xue Zuo Zhi‐Yong Jiang Xue‐Mei Zhang Hong‐Ling Wang Ji‐Jun Chen 《Helvetica chimica acta》2011,94(1):122-126
Two new C20‐diterpenoid alkaloids, named aconicarchamines A and B ( 1 and 2 , resp.), were isolated from Aconitum carmichaelii. By UV, IR, MS, and 1D‐ and 2D‐NMR analyses, their structures were elucidated as 14,17‐dihydro‐14,17‐dihydroxyajabicine and 15‐O‐acetyllassiocarpine. Compound 1 is the third C20‐diterpenoid alkaloid with the lycoctine skeleton bearing an exocyclic C‐atom at C(14). 相似文献
180.
Synthesis of bi-functional silica particles by a simple wet chemical method is described where the mixture of ultra fine nanoparticles (1-3 nm) of titania and silver were attached on the silica particle surface in a controlled way to form a core-shell structure. The silica surface showed efficient bi-functional activity of photo-catalytically self cleaning and antibacterial activity due to nanotitania and nanosilver mutually benefiting each other's function. The optimum silver concentration was found where extremely small silver nanoparticles are formed and the total composite particle remains white in color. This is an important property in view of certain applications such as antibacterial textiles where the original fabric color has to be retained even after applying the nanosilver on it. The particles were characterized at each step of the synthesis by X-ray photoelectron spectroscopy, UV-visible spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and electron energy loss spectroscopy. Bi-functional silica particles showed accelerated photocatalytic degradation of methylene blue as well as enhanced antibacterial property when tested as such particles and textiles coated with these bi-functional silica particles even at lower silver concentration. 相似文献