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1.
1INTRoDUCTIONFollowingpublicationofthefirstsynthesisofamononuclearisothiazoleinl956(li,thisringsystemhasattractedconsiderableinterest.Especially,thistenden-....1cyisincreasingsincealotOfreportsaboutexcellentbiologicalactivitiesofcompoundscontainingisothiazolemoietyemergerecently"~".Theincreasingunderstandingofthefundamentalchemistryoftheisothiazolesystemhasenabledchemiststoincorpo-ratetheringintoawidevarietyofcompoundswithpotentialbiologicalactivity.Inanattempttolookforbiologicallyactivec…  相似文献   

2.
1INTRoDUCTIONAlotofresultsoncobaltcomplexstructureshavebeenreportedforseveraldecades.Theinterestofresearchinthisfieldhasneverbeenreducedbecausethecobaltcomplexesplayaveryimportantroleinthelifescienceandcatalysis,etc[1-6).WereportherethesynthesisandstructureofcomplexCo(C,NO,H'),.H,O.2EXPERIMENTALAllreagentsandsolventsusedareofARgradefromcommericalsourceswithoutfurtherpurification.ThetitlecompoundCo(C,NO,H,),.H,Owassynthesizedbythefollowingmethod.When2.4g(ca.1mmol)ofCoCl2.6H2Ow…  相似文献   

3.
SynthesisandCrystalStructureofNeodymiumComplex[Nd(C_6H_4OHCHNC_2H_4NCHC_6H_4OH)(NO_3)_3(CH_3SOCH_3)]ZHANGMin;KONGFan-Rong;ZHUHui-J...  相似文献   

4.
1 INTRODUCTION Supramolecular approaches to self-assembly of infinite molecular solids with novel structural topo- logies attract considerable attention for their po- tential applications as functional materials and their fascinating architectures[1]. In…  相似文献   

5.
<正> INTRODUCTION. Tripterygium hypoglaucum(Levl)Hutch growing in Hunan,Guangxi,Yunan and Guizhou provinces of China is a plant used as a medicinetreating rheumarthritis. All alkaloids contained within this plant arecharacterzed by antiinflammatory and analgetic. Using column partitionchromatography of silica gel, we have separated out the wilforine and wilforgine from root of this plant.  相似文献   

6.
1 INTRODUCTION Orotic acid (H3dtpc), an important pyrimidine derivative as the effective precursor in the biosynthesis of pyrimidine base of nucleic acids in living organisms, plays a unique role in bioinorganic and pharmaceutical. Aside from the biological interest, orotic acid is also interesting in coordination chemistry. Its ketonic and enolic tautomers along with asymmetric geometry make it to be a very good versatile polydentate ligand[1~5]. The incorporation of metals into supram…  相似文献   

7.
1 INTRODUCTION The self-assembly of organic-inorganic hybrid ma- terials is an intriguing area, which is yielding new generations of supramolecular architectures[1, 2]. Coor- dination by transition metals with multifunctional ligands is one of the main design principles. As a rigid multi-dentate ligand, 5-aminoisophthalic acid (AIP) has received considerable attention owing to the variety of bridging abilities[3~8]. It can engage in three types of intermolecular interactions: (1) M-L b…  相似文献   

8.
OH基与乙炔(乙烯)的反应是控制大气中OH基浓度的重要化学反应。对反应OH+C_2H_2,1975年Davis等用FP-RF技术测定了反应的速率常数。1977年,Perry又用同样方法对该反应作出了研究;结果表明,此反应的速率常数强烈地依赖于压力,与Davis等人的实验结果不符。对反应OH+C_2H_4,Atkinson等人的实验研究表明,压力在30.0kPa以下,反应的速率常数随压力而改变;而在30.0—88.4 kPa之间,与压力无关.这与前人的结果不同。两个反应的产物也因温度不同而异.此外,上述反应一般是在近101kPa下发生的,而实验结果大多是在低压下获得的。且目前尚无直接的理论计算结果。为此,我们在从头算水平上用统计热力学方法,对反应  相似文献   

9.
1 INTRODUCTION In recent years, the design and synthesis of metalorganic coordination polymers have attracted considerable attention, for such supramolecular assemblies have interesting structures as well as potentiaapplications as smart optoelectronic, magnetic andporous materials. By judicious selection of ligandand metal coordination geometries, control over thetopology and geometry of the infinite networks canbe gained. As neutral donor ligands, 4,4?-bpy, pyrazine and imidazole which …  相似文献   

10.
1INTRODUCTION The construction of metal-organic coordination polymers based on covalent interactions[1]or supra-molecular contacts such as hydrogen-bonding and/orπ-πinteractions)[2]is now of great interest not only due to the enormous variety of intriguing structural topologies themselves,but also to their unexpected physical and chemical properties for potential prac-tical applications as functional materials.Many N-containing ligands,such as4,4?-bipyridine,2,2?-bi-pyridine and1,10-phen…  相似文献   

11.
<正> [Tm4 (p-NO2C6H4CO2)12 (H2O)10]·2H2O, Mr = 2885. 28, triclinic, space group P1 with a=14. 109(4) ,b= 14. 594(3) ,c= 13. 638(3) A ,α= 107. 04 (2), β=103. 36(2),γ= 93. 93(2)°, Z=1,V = 2584(1) A3.F(000) = l416,μ = 36. 4cm-1(Moka) ,Dc=1. 85g·cm3. The final R factor is 0. 034. The crystal structure is composed of tetrameric units in which four metal ions are bridged by carboxyl groups in chain form.  相似文献   

12.
(C5H4CH3)3Ho和(C5H4CH3)2Ho(C5H5)与5-苯基四唑(HN4CPh)在THF中反应,得到复合产物[(C5H4CH3)2HoN4CPh]2·[(C5H4CH3)(C5H5)HoN4CPh]2,该晶体属三斜晶系,P1空间群,晶胞参数为a=9.386(3),b=13.071(3),c=16.571(2)A,a=86.90(1),β=74.61(2),γ=77.30(2)°,V=1912.2(8)A3,Z=1,Dc=1.602g/cm3,Mr=922.61,μ=41.92cm-1,F(000)=896,最终偏离因子R=0.041,Rw=0.056.晶体数据显示,在同一个晶胞里有两个组成不同的分子,每一个分子都是具有对称中心的四唑基桥二聚体结构,其桥环单元-HoN3HoN3-是平面型的。每个钬原子分别被两个茂基和3个四唑基氮原子配位,形成1个边桥变形四面体构型。  相似文献   

13.
<正> INTRODUCTION. The five-coordinated silicon atoms in the 1-aryloxy derivatives of the silatrane series are surrounded by four oxygen atoms (three in equatorial- and one in apical position). The only known crystal structure of the 1-aryloxy silatrane derivatives is that of 1-m-chlorophenoxysilatrane and we performed the structure determination of the title compound to throw light upon the effect of the phenyl ring substituent on the Si←N dative bond.  相似文献   

14.
1 INTRODUCTION More than 200 known metalloenzymes of a wide variety of types have been shown to contain zinc centers at their active sites (such as hydrolases, ligases and anhydrases)[1~3]. The active zinc centers in biological systems are usually surro…  相似文献   

15.
<正> Mr = 431,.6 orthorhombic,P212121,a = 8.526(2), b = 9.970(2), c= 29.787(6)X,Z=4,V=2532.0A3,Dc=1.132g.cm-3,λ(MoKα)=0.71073A,μ=0.67cm-1, F(000) = 952, final R= 0.069 for 1733 observed reflections with I>1σ(I). All six-membered rings in this free base are in the chair form and the five-membered ring C takes the envelope conformation, with the ring fusions A/B traps, B/C trans, C/D cis, D/E trans and E/F trans. There is one crystal water whose oxygen atom joins the adjacent alkaloid molecules by the inter-molecular hydrogen bonds O(1)-H... 0(3)-H(31)...0(2)=C(6). Pertinent parameters for the hydrogen bonding system are: .0(1)...0(3) 2.878(6), 0(2)...O(3) 2.917(6)A,O(1)-H...O(3) 178.3(3)°,and 0(3)-H(31)...0(2) 165.6(3)°.  相似文献   

16.
A new bismuth oxalate Na(C5NH6)[Bi(H2O)(C2O4)2]2·4H2O has been obtained under hydrothermal conditions and characterized by X-ray diffraction. It crystallizes in monoclinic, space group C2/m with a = 12.020(5), b = 11.190(8), c = 11.067(10)A, β= 121.78(2)°, NaBi2C13NH18O22, Mr= 981.24, V = 1265.4(16) A^3, Z = 2, Dc = 2.575 g/cm^3,μ(MoKcr) = 14.005 mm^-1, F(000) = 912, R = 0.0179 and wR = 0.0394. In the structure, the Bi(III) centers are interconnected by oxalate ligands to produce honeycomb-like layers, which are further pillared by bridging ligand oxalate molecules to form a 3-D open-framework structure. Furthermore, the title compound exhibits blue luminescence with the emission peaks located at 394nm in the solid state at room temperature, and thus it could be useful in the field of photoactive materials.  相似文献   

17.
在自然界中,α-羟基羧酸广泛的存在于动植物体内,在羧酸循环、碳水化合物代谢和氨基酸的合成中起到重要的作用。Tapscott等详细总结了有关羟基羧酸及其金属配合物的合成化学[1]。芴的9位上2个氢原子被羟基和羧基取代可生成9-羟基-芴-9-羧酸(简称芴酸),它是α-羟基乙酸的衍生物,是一种具有生理活性的植物生长整形素,它能够延缓植株生长,影响植株根的向地性和茎的向光性[2]。由于芴酸含有羟基和羧基两种不同的氧配位原子,使其又可以作为一种潜在的构筑配合物的组织基元。目前有关芴酸与金属离子的合成与结构化学研究相对较少,仅见铜、镉的单…  相似文献   

18.
<正> {Ni C(C4H9O)2PS2] (C12H8N2)2} [C(C4H9O)2PS2], Mr= 795. 60, Monocinic,P2,/n,a=16. 806(2), b=12. 720(2), c=21. 248(2) A. β=98. 454(7)°, V = 4493A3,Z=4,Dc= 1. 18g·cm-3,Mo Ka radiation,A=0. 71069A ,F(000) = 1664, R=0. 102 for 4154 reflections with I≥3σ(I).The crystal structure consists of complex cation {NiC(C4H9O)2PS2](C12H8N2)2}+ and complex anion C(C4H9O)2PS2]-. In the cation, nickel (Ⅱ) atom is coordinated by four nitrogen atoms and two sulfur atoms to form a distorted octahedron.  相似文献   

19.
1 INTRODUCTION The researches on transition metal coordination complexes have been rapidly expanded because of their fascinating structural diversity and potential applications[1~4]. As we know, zirconium oxalates can be used as precursors in the synth…  相似文献   

20.
<正> INTRODUCTION. The derivatives of ferrocene are found to be increasingly used in the area of the catalysis of combustion reactions of high energy fuels and new material research. Therefore, more attention has been paid to these compounds. This work is a part of our systematic investigation on a  相似文献   

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