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21.
YUAN Li  LU Wen-Guan 《结构化学》2011,30(8):1207-1213
A new 3D metal-organic framework of {[Co3(IDC)2(bipy)2(py)2]·7H2O}n (1) was obtained by the hydrothermal reaction of Co(NO3)2·6H2O, imidazole-4,5-dicarboxylic acid (H3IDC), 4,4'-bipyridine (bipy), and pyridine (py), and structurally characterized by elemental analysis, infrared spectroscopy, thermal gravimetric analysis, and single-crystal X-ray diffraction. X-ray diffraction crystal structural analysis reveals that it crystallizes in orthorhombic system, space group Pccn with a = 11.1040(3), b = 19.8834(5), c = 21.3025(5), V = 4703.3(2)3, Mr = 1079.63, Z = 4, Dc = 1.525 Mg·m-3, F(000) = 2212, μ(CuKα) = 8.855 mm-1, the final R = 0.0331 and wR = 0.0713 for 2525 observed reflections with I ≥ 2σ(I). In compound 1, each cobalt(II) ion is six-coordinated with a slightly distorted octahedral coordination geometry, and each μ3-IDC3- acts as a bridge to bond three neighboring Co(II) ions, leading to an infinite 2D network layer structure of [Co3(IDC)2]n with Kagomé lattice. The adjacent layers are further linked by μ2-bipy to form an infinite 3D layered-pillared framework architecture of [Co3(IDC)2(bipy)2(py)2]n.  相似文献   
22.
用量子化学密度泛函方法结合导体极化连续模型研究了具有潜在抗肿瘤活性的NAMI-A型钌配合物(HL)[trans-RuCl4L(dmso-S)](L=1-methyl-1,2,4-triazole,dmso-S=S-dimethyl sulfoxide) (1)的水解反应过程.计算得到该配合物水解反应过程中相应的结构特征和详细的反应势能面.对于第一步水解,液相中配合物1的活化能垒比已经报道的抗肿瘤药物(Him)[trans-RuCl4(  相似文献   
23.
The hydrolysis process of Ru(III) complex (HL)[trans-RuCl4L(dmso-S)] (L=1-methyl-1,2,4-triazole and dmso-S=S-dimethyl sulfoxide) (1), a potential antitumor complex similar to the well-known antitumor agent (Him)[trans-RuCl4L(dmso-S)(im)] (NAMI-A, im=imidazole), was investigated using density functional theory combined with the conductor-like polarizable continuum model approach. The structural characteristics and the detailed energy profiles for the hydrolysis processes of this complex were obtained. For the first hydrolysis step, complex 1 has slightly higher barrier energies than the reported anticancer drug NAMI-A, and the result is in accordance with the experimental evidence indicating larger half-life for complex 1. For the second hydrolysis step, the formation of cis-diaqua species is thermodynamic preferred to that of trans isomers. In addition, on the basis of the analysis of electronic characteristics of species in the hydrolysis process, the trend in nucleophilic attack abilities of hydrolysis products by pertinent biomolecules is revealed and predicted.  相似文献   
24.
吲哚-3-乙醛酸甲酯和3-吲哚乙腈在碱存在下,以烷基卤或硫酸烷基酯为亲电试剂进行N-烷基化反应,合成了6种新的N-烷基化吲哚化合物。 研究了吲哚化合物及烷基化试剂的结构、溶剂和碱对N-烷基化反应的影响。 具有强吸电子取代基的吲哚-3-乙醛酸甲酯使用弱碱Cs2CO3在室温就可顺利进行烷基化反应,产率达到93%;而具有较弱吸电子取代基的3-吲哚乙腈,需要使用强碱NaH才能进行烷基化反应。  相似文献   
25.
谢楠柱 《物理》2007,36(1):46-50
文章评述了国际医学物理学近印年的新发展,着重介绍了数字影像物理学和放射治疗物理学的新进展及其对临床应用高新医疗器械的重要作用,并谈及国际医学物理学的新发展对中国医学物理学发展的启示.  相似文献   
26.
新型双吲哚马来酰亚胺衍生物的合成   总被引:1,自引:0,他引:1  
以1-(3-氧代四氢吡喃丙基)-吲哚-3-乙醛酸甲酯(5)和吲哚-3-乙酰胺(6)为原料,在催化剂叔丁醇钾的四氢呋喃溶液存在下发生偶合反应,经浓盐酸处理得脱保护的中间体7,再经甲磺酰化反应、氨解反应得到4种新的具有不同氨烷基侧链的双吲哚马来酰亚胺衍生物9a,9b,9d,9e.目标产物结构通过1H NMR,13C NMR,MS和HRMS确证.  相似文献   
27.
Enzymatic hydrogelation is a totally different process to the heating‐cooling gelation process, in which the precursors of the gelators can be involved during the formation of self‐assembled structures. Using thixotropic hydrogels formed by a super gelator as our studied system, we demonstrated that the enzyme concentration/conversion rate of enzymatic reaction had a strong influence on the morphology of resulting self‐assembled nanostructures and the property of resulting hydrogels. The principle demonstrated in this study not only helps to understand and elucidate the phenomenon of self‐assembly triggered by enzymes in biological systems, but also offers a unique methodology to control the morphology of self‐assembled structures for specific applications such as controlled drug release.  相似文献   
28.
The title compound N-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-quinoxaline-2-methanamide(4, C23H27N5O3, Mr = 421.50) was synthesized via a four-step reaction and characterized by 1H NMR, 13 C NMR, ESIMS and single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 12.108(2), b = 12.639(3), c = 14.601(3) , β = 104.87(3)o, V = 2159.6(8) 3, Z = 4, Dc = 1.296 g/cm3, S = 1.023, μ = 0.088 mm-1, F(000) = 896, R = 0.0392 and w R = 0.0983 for 2836 observed reflections with I 2σ(I). The single-crystal X-ray structural analysis reveals that 4 is stabilized by intramolecular and intermolecular hydrogen bonds together with π-π interactions. The bioassay showed that 4 exhibited high selective activity for α1A/D vs. α1B-adrenoceptors subtype.  相似文献   
29.
An organocatalytic sequential α-amination/Grignard addition reaction of aliphatic aldehydes is reported. The synthetically useful anti-vicinal amino alcohol derivatives were obtained in high yields and with high stereoselectivities. These derivatives could be easily transformed into oxazolidinones.  相似文献   
30.
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