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1.
Introduction Chirality is defined as the absence of inversion symmetry,however,it is actually a pseudo-scalar of objects or figures,and does not depend for its definition on any connection to the physical world[1-5]. Logically,chiral molecules may possess other inherent physical quantity that guarantees the connection to the physical world[6,7].  相似文献   

2.
王瑾玲  杨云  张欣  缪方明 《结构化学》2003,22(6):677-680
1 INTRODUCTION 4-Acyl-5-pyrazolone, a family of flexible b- diketonate, is widely used as extract[1] and well known for its applications as analgesics, antipyre- tics, anti-inflammatory and insecticides[2]. Therefore the study on the derivation of 4-acyl-5-pyrazolone is the focus of many research groups working in the fields of coordination chemistry, biomedicine and pharmaceutical chemistry. In order to study the rela- tionship between the structure and performance of these compounds, w…  相似文献   

3.
1 INTRODUCTION Pagodane (Fig. 1) first synthesized[1] in 1983 has been studied by Prinzbach and coworkers for more than twenty years[2, 3]. Described as a waxy solid melting without decomposition and stable to at least 600 ℃ in gas phase, pagodane is interesting for its exotic structure and as an introduction to the family of substituted dodecahedranes[2]. Owing to its unu- sual structure, pagodane has provided experimenters and theorists with a challenge to characterize and cal- culate …  相似文献   

4.
1INTRODUCTION Antipyrine(2,3-dimethyl-1-phenyl-5-pyrazolone)and its derivatives exhibit a wide range of biological activities and applications[1~3].Antipyrine shows mi-nimal protein binding and is rapidly and completely absorbed from the gastrointestinal tract and exten-sively metabolized by the cytochrome P450liver en-zymes[4].Estimates of half-life and systemic cleara-nce of antipyrine have been used for the in vivo asse-ssment of hepatic drug oxidation in different spe-cies[5].Owing to…  相似文献   

5.
吴传德  林祥 《结构化学》2001,20(4):266-269
1 INTRODUCTION Polyoxometalates (POM) are of great interest not only for their structural variety but also their unexpected properties[1,2]. These inorganic anions had been widely investigated as divers as catalysis, biology, medicine, magnetochemistry, and materials science[3~5]. The molybdenum in its higher oxidation states is easy to form poly-nuclear anionic metal-oxygen clusters and many giant poly- molybdates with extraordinary variety of the relevant topology and electronic struct…  相似文献   

6.
1 INTRODUCTION Triazole, a five-membered heterocyclic compound with three nitrogen atoms, is an important interme- diate product of medicine and chemical industry as well as insecticide [1]. Due to its small volume and high nitrogenous density, triazole holds more and more attraction for the material researchers, espe- cially the researchers of high-energy insensitive explosive. It is reported that its nitro and amino deri- vatives are a sort of important high-energy mate- rials[2]. Previ…  相似文献   

7.
正Hydrogen has been considering as a promising renewable energy source and a viable alternative for fossil-fuels in the future [1,2]. Hydrogen oxidation reaction (HOR) and its reverse reaction are two significant reactions for applying hydrogen as electrochemical energy. On the other hand,platinum is believed to be the best electrocatalyst for HOR,although several drawbacks including high cost, scarcity,low CO tolerance, and depressed catalytic activities in alkaline environments, hinder the development of hydrogen application [1]. Hence, it is highly desired to develop Pt-free HOR catalysts with high activity, high stability, low cost, and good resistance to CO poisoning [3].  相似文献   

8.
1 INTRODUCTION Polyoxomolybdates have been of great interest due to their unique structural varieties, associated multitude of properties and applications as catalysis, medicine and material[1, 2]. One of the most impor- tant aspects is the synthesis and investigation of the materials on polyoxomolybdates containing organo- metallic groups[3~5]. Such materials can provide molecular models for heterogeneous catalysis and display cooperative effects or bifunctional catalytic activity[6]. O…  相似文献   

9.
1 INTRODUCTION As the first inorganic antitumor complex[1], cis- platin (cis-DDP) possesses prominent therapeutic ef- fect for encephaloma, lung cancer and several kinds of genital system tumors[2]. However, cis-DDP has toxic side-effect to a larger extent. Especially due to its damage to kidney, the dose is strictly limited[3]. Therefore, other Pt(II) complexes including carbon- platin were developed[4]. Pd(II) complex is struc- turally similar to Pt(II) complex, so the antitumor …  相似文献   

10.
1 INTRODUCTION Antipyrine (2,3-dimethyl-1-phenyl-5-pyrazolone) and its derivatives exhibit a wide range of biological activities and applications[1~3]. Antipyrine shows mi- nimal protein binding and is rapidly and complete- ly absorbed from the gastrointestinal tract and exten- sively metabolized by the cytochrome P450 liver en- zymes[4]. Estimates of half-life and systemic clear- ance of antipyrine have been used for the in vivo as- sessment of hepatic drug oxidation in different spe- c…  相似文献   

11.
温德才  刘世雄 《结构化学》2007,26(11):1281-1286
Two complexes,Cu(HnicO)2 1 and Ni(HnicO)2(H2O)2 2 (H2nicO=2-hydroxy-nicolinic acid),were synthesized by hydrothermal reactions and structurally characterized. Complex 1 crystallizes in monoclinic,space group P21/n,with a=8.314(7),b=6.275(4),c=11.283(7),β =98.32(3)°,V=582.5(7)3,Z=2,Mr=339.74,Dc=1.937 g/cm3,F(000)=342,μ=1.908 mm-1,S =1.097,the final R=0.0284 and wR=0.0781 for 1177 observed reflections with I > 2σ(I). Complex 2 crystallizes in monoclinic,space group P21/c,with a=7.438(5),b=12.22(1),c=7.537(5),β=100.07(3)°,V=674.3(8)3,Z=2,Mr=370.95,Dc=1.827 g/cm3,F(000)=380,μ =1.487 mm-1,S=1.041,the final R=0.0335 and wR=0.0779 for 1202 observed reflections with I > 2σ(I). There are extended 3D framework structures in complexes 1 and 2 due to the N–H…O and C–H…O hydrogen bonds. The copper atom in 1 has square planar coordination,while the nickel atom in 2 adopts octahedral coordination geometry. The TG curve shows that complex 2 is stable in solid state to 150 ℃.  相似文献   

12.
Two novel cobalt(Ⅱ) compounds were obtained and characterized by X-ray single-crystal diffraction,IR,1H NMR and elemental analysis.Compound 1 crystallizes in monoclinic,space group P21/n,with a = 18.046(4),b = 11.335(3),c = 19.157(5) ,β = 92.707(3)o,Z = 4,V = 3914.4(16) 3,Mr = 968.56,Dc = 1.644 g/cm3,μ = 1.378 mm-1,F(000) = 1960,the final R = 0.0367 and wR = 0.0895.The crystal of compound 2 is of monoclinic,space group P21/c with a = 8.7253(10),b = 10.9031(13),c = 18.235(2) ,β = 93.2210(10)o,Z = 4,V = 1732.0(3) 3,Mr = 464.21,Dc = 1.780 g/cm3,μ = 1.560 mm-1,F(000) = 932,the final R = 0.0322 and wR = 0.0743.  相似文献   

13.
Reaction of SmI2(THF)x with 2 equivalents of NaOAr (Ar = C6H2-tert-Bu3-2,4,6)1,2-dimethoxyethane (DME) leads to the ligand-exchange reaction, and a DME-solvated complex of Sm(Oar)2(DME)2 2 was obtained. Complex 1 crystallizes in monoclinic, space group P21/c with a =10.366(5), b = 33.024(15), c = 16.123(7) (A), β= 93.197(8)°, V= 5511(4) A3, Z= 4, C52H9oO6Sm, Mr = 961.59, Dc = 1.159 g/cm3, F(000) = 2048,μ(MoKα) = 1.107 mm-1, R = 0.0844 and wR = 0.1401for 4694 observed reflections. Complex 2 crystallizes in monoclinic, space group C2/c with a =27.222(5), b = 10.6140(19), c = 17.398(4) (A), β = 110.245(3)°, V = 4716.4(16) (A)3, Z = 4,C44H78O6Sm, Mr = 853.41, Dc = 1.202 g/cm3, F(000) = 1808,μ(MoKα) = 1.285 mm-1, R = 0.0361and wR = 0.0830 for 5210 observed reflections.  相似文献   

14.
1 INTRODUCTION Self-assembly through coordination and hydrogen bonds has been proved to be a powerful tool for con- structing functional organic crystalline materials[1~4]. Except for the important role of H-bonds in the sta- bilization of structures, hydrogen bonding groups namely hydroxyl, amide groups in adjacent coor- dination polymeric chains or discrete lamellas can form hydrogen bonds, which allow for the assembly of well-formed crystalline solid[5, 6]. Our recent inte- rest is foc…  相似文献   

15.
The title complex Pd(H2BDA)Cl2(2DMSO (C16H14Cl2N2O6PdS2, H2BDA = 2,2'- bipyridine-3,3'-dicarboxylic acid) has been synthesized and characterized by IR spectra, elemental analysis and 1H NMR spectra. Its structure was determined by single-crystal X-ray diffraction analysis. The complex crystallizes in the monoclinic system, space group P21/c with a = 1.3604(6), b = 1.2606(6), c = 1.3521(6) nm, β = 103.677(7)°, V = 2.2530(17) nm3, Mr = 571.75, Z = 4, Dc = 1.686 g/cm3, μ = 1.280 mm-1, F(000) = 1136, R = 0.0405 and wR = 0.0908. The complex presents a planar quadrangle arrangement and is assembled via hydrogen bonds.  相似文献   

16.
Two cobalt(Ⅱ) compounds,Co(2,2-bpy) 2 Br 2 (1,2,2-bpy=2,2-bipyridyl) and Co(1,10-phen) 2 Br 2 (2,1,10-phen=1,10-phenanthroline),have been prepared under ionothermal reactions using the 1-propyl-3-methylimidazolium bromide ionic liquid solvent.Single-crystal X-ray analyses reveal that 1 crystallizes in a monoclinic space group P2 1 /c,with a=8.5509(13),b=14.804(2),c=15.650(2),β=97.119(2) o,V=1965.8(5) 3,Z=4,C 20 H 16 Br 2 N 4 Co,M r=531.12,D c=1.795 g/cm 3,μ=4.950 mm-1,F(000)=1044,the final R=0.0467 and wR=0.0736 for 2291 observed reflections with I > 2σ(Ⅰ).Complex 2 crystallizes in a monoclinic space group P2 1 /n,with a=10.4237(8),b=16.8657(12),c=12.4945(9)b,β=102.110(1) o,V=2147.7(3) 3,Z=4,C 24 H 16 Br 2 N 4 Co,M r=579.16,D c=1.791 g/cm 3,μ=4.540 mm-1,F(000)=1140,the final R=0.0431 and wR=0.1042 for 3470 observed reflections with I > 2σ(Ⅰ).The mononuclear molecules of 1 are linked by the C-H···Br hydrogen bonds and π-π interactions to form a three-dimensional supramolecular framework structure.The C-H···Br hydrogen bonds and π-π interactions link the mononuclear molecules of 2 to give a two-dimensional layer structure.  相似文献   

17.
The title compounds, Cu(L1)(C4H8NHO) and Ni(L2)(C4H8NHO) (H2L1 = 5-bro- mosalicylaldehyde-p-nitrobenzoylhydrazone, H2L2 = 5-bromosalicylaldehyde-p-hydroxybenzo- ylhydrazone), have been obtained and characterized by single-crystal X-ray diffraction. Complex 1 belongs to the triclinic system, space group P1 with a = 8.6960(2), b = 9.957(2), c = 11.878(2) , α = 73.36(3), β = 78.25(3), γ = 82.64(3)o, V = 962.1(3) 3, Mr = 512.81, Z = 2, F(000) = 514, Dc = 1.770 g/cm3, μ(MoKα) = 3.251, R = 0.0337 and wR = 0.0846. Complex 2 is of monoclinic, space group P21/c with a = 13.313(2), b = 8.2096(1), c = 21.890(3) , β = 125.737(3)o, V = 1941.9(4) 3, Mr = 478.97, Z = 4, F(000) = 968, Dc = 1.638 g/cm3, μ(MoKα) = 3.085, R = 0.0356 and wR = 0.0817. The ligands form a satisfactory N2O2 square plane around the metal centers in two compounds. Different patterns of hydrogen bonds are observed owing to the presence of different substituents on aromatic ring of the acylhydrazone Schiff bases. In complex 1, square-planar copper(II) complexes are linked by intermolecular hydrogen bonds leading to zigzag infinite chains. In complex 2, the metal complexes are linked via hydrogen bonds to form corrugated sheets in a staggered fashion; 3D channels along the b axis are constructed through other non-covalent interactions between the neighboring layers.  相似文献   

18.
A μ1,1,3 formic bridging Ni2 complex [Ni3(HCOO)6·H2O]]n 1 has been synthesi-zed under hydrothermal conditions. The single-crystal X-ray diffraction analysis shows that 1 exhibits a 3D open microporous tube formed by covalent and coordination bonds. Complex 1 crystallizes in the monoclinic system, space group P21/c with a = 11.1487(13), b = 9.7763(11), c =17.9685(17) A, β= 126.948(6)°, C6H6Ni3O13, Mr = 462.02, V = 1565.2(3) A3 Z = 4, Dc= 1.961 g/cm3, μ = 3.630 mm-1, F(000) = 917.7, Rint = 0.0234, the final R = 0.0234 and wR = 0.0734 for 3469 observed reflections (Ⅰ>2σ(Ⅰ)).  相似文献   

19.
1 INTRODUCTION In recent years, the assembly of extended supra- molecular architectures from molecular building units has yielded a new generation of materials with diverse network topologies[1~3]. A number of such frameworks have been found to exhibit fascinating physical and chemical properties. The investigation of hydrogen bonding is important for many practical applications, such as the design of antibiotics and development of new materials with programmed properties[4]. A great va…  相似文献   

20.
Two new binary cocrystals formulated as POM·NBA 1 and POM·DNSA 2 (POM = 3-methyl-4-nitro-pyridine-N-oxide, NBA = o-nitrobenzoic acid, DNSA = 3,5-dinitrosalicylic acid) have been successfully synthesized and characterized by elemental analysis, IR and X-ray single- crystal diffraction analysis. The crystal of 1 crystallizes in triclinic, space group P1, with a = 7.621(4), b = 7.816(4), c = 11.702(5) , α = 87.957(10), β = 83.642(10), γ = 81.535(10)o, C13H11N3O7, Z = 2, Mr = 321.25, V = 685.1(6) 3, Dc = 1.557 g/cm3, F(000) = 332, μ = 0.129 mm-1, the final R = 0.0632 and wR = 0.0831. The crystal of 2 crystallizes in monoclinic, space group P21/c with a = 14.910(9), b = 5.904(3), c =19.321(12) , β = 110.583(10)o, C13H10N4O10, Z = 4, Mr = 382.25, V = 1592.1(16) 3, Dc = 1.595 g/cm3, F(000) = 784, μ = 0.140 mm-1, the final R = 0.0598 and wR = 0.1589. Further structure analysis reveals that the POM with NBA and DNSA molecules in 1 and 2 are linked into 3D structures by the combination of strong O–H…O and weak C–H…O hydrogen bonds, π…π stackings and diverse short contacts, in which different C–H…O weak hydrogen bonds may play a key role in constructing the network structures.  相似文献   

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