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971.
3 Substitutedisoindolin 1 ones (2 ,3 dihydro 1H isoindolin 1 ones)ofgeneralstructure (1)constitutethekeystructuralfeatureofalargenumberofbioactivemoleculesofnaturalorsyntheticorigin .Forexample ,lennoxamine (2 ) ,1nuevamineandchileninearealkaloidsisolatedfromvarious… 相似文献
972.
Hydrothermal Synthesis and Electrochemical Properties of Complex Cu(CH3C6H4COOH)2(2,2''-bipy)·(H2O) 总被引:1,自引:0,他引:1
The title complex has been synthesized by 4-methylbenzoic acid and 2,2'-bipyridine (bipy) in the mixed solvent of water and methanol. It crystallizes in the triclinic system, space group (P1-) with a = 0.7047(3), b = 1.1217(5), c = 1.6718(7) nm, α = 103.826(7), β = 90.772(6), γ = 104.195(6)°, C26H25CuN2O5.50, Mr = 517.02, V = 1.2404(9) nm3, Dc = 1.384 g/cm3, Z = 2, F(000) = 536, μ(MoKα= 0.921 mm-1, R = 0.0782 and wR = 0.2172. Structural analysis shows that the copper atom is coordinated with three oxygen atoms from two 4-methylbenzoic acids and one water molecule together with two nitrogen atoms from 2,2'-bipyridine, giving a distorted square-pyramid coordination geometry. The cyclic voltametric behavior of the complex has also been described. 相似文献
973.
Carlos Vázquez-Vázquez M. Arturo López-Quintela 《Journal of solid state chemistry》2006,179(10):3229-3237
The synthesis of La1−xAxMnO3 (A=Ca, Sr, Ba) nanoparticles in nonaqueous solvents has been studied. For this solvothermal procedure benzyl alcohol and acetophenone were chosen as reaction media. After this treatment in mild conditions a precipitate was obtained, which, however, can be annealed to the crystalline perovskite structure. Our results show that acetophenone is more suited to obtain the clean pervoskite phase than benzyl alcohol. 相似文献
974.
E. A. Belousova V. V. Koval N. I. Rechkunova S. Kh. Degtyarev O. S. Fedorova O. I. Lavrik 《Russian Chemical Bulletin》2005,54(5):1306-1310
The interaction of DNA polymerase Tte from Thermus thermophilus B35 with dUTP analog containing a fluorescein residue bound to C(5) of the base (Flu-dUTP) was studied by fluorescence titration.
The dissociation constants of the enzyme—substrate complexes in the absence and in the presence of a DNA duplex containing
an extended template and bivalent metal ions and the kinetic parameters of polymerization by DNA polymerase Tte in the presence of Flu-dUTP were determined.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1268–1272, May, 2005. 相似文献
975.
M. Carolina Navarro Silvina Pagola Raúl E. Carbonio 《Journal of solid state chemistry》2005,178(3):847-854
The crystal structure of Nd[Fe(CN)6]·4H2O has been refined by Rietveld analysis using high resolution synchrotron powder X-ray diffraction data. It belonged to the orthorhombic crystal system, Cmcm space group, with cell parameters: , and . The change in space group from P63/m which is observed in the pentahydrates (LnFe(CN)6·5H2O) to Cmcm in the tetrahydrates has been analyzed to be a consequence of the change in 9-fold coordination of Nd3+ in the pentahydrates to 8-fold coordination in the tetrahydrates, which changes the Nd3+ environment from tricapped trigonal prism to a distorted tricapped trigonal prism or square antiprism. Its decomposition process in air to produce NdFeO3 has been followed by thermogravimetric and differential thermal analysis, IR spectroscopy and laboratory powder XRD. We found that it is possible to synthesize crystalline NdFeO3 at temperatures as low as 380 °C and refine the structure of single phase crystalline NdFeO3 synthesized by this method at 600 °C. 相似文献
976.
有机-无机杂化材料因其在催化、化学吸附、磁性和电子导体等方面具有广泛的应用而成为人们的研究热点[1,2]. 通过过渡金属离子和特殊的有机配体之间的反应, 一系列具有独特结构的配位聚合物已被合成出来. 多齿有机配体可螯合两个或多个金属离子, 这些金属离子之间存在良好的电子交换[3], 可形成一维、二维或三维的配位聚合物. 均苯三甲酸和均苯四甲酸都是良好的桥连多齿配体, Chui等采用均苯三甲酸合成了具有吸附作用的大孔道的[Cu3(tma)2(H2O)]n[4] (tma=benzene-1,3,5-tricarb-oxylate)三维配位聚合物, 并且[Ni(C12H3ON6O2)]3(tma)*H2O[5], [M(tma)2]*12H2O(M=Co,Ni,Zn)[6], Na2[Co(H2O)6(bta)]*4H2O[7] (bta=benzene-1,2,4,5-tetracarboxylate)和[Co(phen)(md)][8] (phen=1,10-phenanthroline, md=benzene-1,3-dicarboxylate)等配位聚合物也先后被合成出来. 相似文献
977.
LIU Xing-Quan WU Yu-Tang JIA Zhao-XiaChengdu Institute uf Organic ChemistryAcademia SinicaChengdu Sichuan To whom correspondence should be addressed. 《天然气化学杂志》1995,(1)
1 , 5-diazabicyclo['1, 3, 0]non-5-ene(DBN) has been synthesized in our laboratory, and its catalytic activity and selectivity for methanol carbonylation to methyl formate (MF) have been studied. The experimental results have demonstrated that the synthetic processes of DBN used for the present work are reasonable and feasible. The total yield of three steps of DBN synthsis is approximate to 80%. The activity evaluation has shown that DBN can effectively catalyze the carbonylation reaction of methanol in the presence of propylene oxide (PO) promoter. PO-promoted DBN is a novel catalytic system superior to sodium methoxide. 相似文献
978.
Synthesis and Crystal Structure of Ag2(admtrz)2(CF3CO2)2(admtrz=4—amino—3,5—dimethyl—1,2,4—triazole)
1 INTRODUCTION Transition metal complexes bridged by 1, 2, 4-triazole group can produce interesting structures and specific properties[1]. Many attempts have been made to synthesize a variety of complexes with paramagnetic centers by using such ligands, and their structures and magnetic properties have been characterized[2]. However, the polynuclear Ag(I) complexes bridged by 1, 2, 4-triazole have been poorly studied[3]. Recently, we have prepared a series of silver(I) triazole complex… 相似文献
979.
Stereoselective synthesis of (3S,4S)- and (3R,4R)-series of 3,4-dihydroxyglutamic acids was investigated. The key reaction in this synthesis is asymmetric reduction of meso-imide derived from meso-tartaric acid. Lewis acid-promoted cyanation of the obtained optically active lactam via the acyliminium intermediate followed by standard deprotection procedure afforded the desired 3,4-dihydroxyglutamic acids. 相似文献
980.