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1.
Introduction Flavonoids exist widely in edible plants, and have pharmacological activity. They played a major role in the successful medical treatments at ancient times, and their uses have been persevered up to now.1-3 Flavonoid sulfates were found in a large number of plant species. They occupy an important position in the field of natu-ral products chemistry since they provide structures consisted of organic and inorganic components. The pharmacological assay revealed that flavonoid sulfat…  相似文献   

2.
1 INTRODUCTION In recent years, extensively attention has been fo- cused on the design and synthesis of d10 metal- based complexes[1, 2]. A series of d10 metal-organic frame- works have been described not only because of their intriguing structures but also due to their ptential ap- plications in photoluminescent fields[3~7]. Although phthalate ligand was successfully used to design and synthesize a wide variety of metal complexes, those containing Cd(II) complex are less considered[8~…  相似文献   

3.
1 INTRODUCTIONCoordination compounds with 1 ,2 ,4 triazole as a ligand have interesting fea tures,notonly because ofthe very interesting magnetic propertiesofthese complex es,but also because ofrich modes ofcoordination〔1〕.Particularly,the coordinationbehavioroftriazoletowardsa numberoftransition metalthiocyanatesshowsremark abledifferences〔2 - 6〕.On unsubstitution at N4 ,thetriazole ring hasmonodentate,1 ,2 and 2 ,4 bridging forms.These three modes were all observed in the Ni( II)…  相似文献   

4.
李秀梅  董艳辉  王庆伟  崔运成  刘博 《结构化学》2007,26(12):1495-1498
A new metal-organic coordination complex [Zn(H2BPTC)(phen)2]n·3nH2O (BPTC = 3,3′,4,4′-benzophenone tetracarboxylate, phen = 1,10-phenanthroline) 1 has been obtained from hydrothermal reaction and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. In compound 1, the zinc cation is hexa-coordinated with two carboxylate oxygen atoms from one H2BPTC ligand and four nitrogen atoms from two different phen ligands, showing a slightly distorted octahedral geometry. Crystal data: C41H30N4O12Zn, Mr = 836.06, monoclinic, P21/c, a = 14.2714(9), b = 16.9386(10), c = 15.0151(9) , β = 101.3420(10)o, V = 3558.8(4) 3, Dc = 1.560 g/cm3, μ(MoKα) = 0.766 mm-1, F(000) = 1720, Z = 4, R = 0.0439 and wR = 0.1157 for 4123 observed reflections with I > 2σ(I).  相似文献   

5.
Synthesis and Crystal Structure of [{Cd(hmbdc)(H_2O)_3}·2H_2O]_n   总被引:1,自引:0,他引:1  
A novel coordination polymer [{Cd(hmbdc)(H2O)3}·2H2O]n (hmbdc = 5-hydroxy- isophthalic acid) has been synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c, with a = 9.599(3), b = 18.699(5), c = 7.557(2) , β = 108.198(4)°, V = 1288.6(6) 3, Z = 4, Mr = 382.60, Dc = 1.972 g/cm3, F(000) = 760, μ = 1.740, the final R = 0.0555 and wR = 0.0995 for 1732 observed reflections with I > 2σ(I). The structural analysis shows that the intermolecular hydrogen bonds and π-π interactions result in a three-dimensional supramolecular framework.  相似文献   

6.
The title compound, [Mn4O2(O2CMe)6(MeOH)2(dbm)2]·2MeCOOH·2CH2Cl2 (Hdbm = dibenzoylmethane), has been synthesized and structurally determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1, with a = 10.729(3), b = 12.269(3), c = 13.085(4) , α = 106.367(3), β = 107.643(2), γ = 94.771(2)o, V = 1547.9(7) 3, Z = 1, C50H64Cl4Mn4O24, Mr = 1410.57, Dc = 1.513 g/cm3, F(000) = 724, Rint = 0.0147, T = 293(2) K and μ = 1.046 mm–1. The final R = 0.0359 and wR = 0.0938 for 5791 observed reflections with I > 2σ(I). The structure of the complex consists of one [Mn4(μ3-O)2]8+ core with four coplanar Mn atoms disposed in an extended “butterfly-like” arrangement and two O atoms triply bridging each “wing”, and the peripheral ligation is provided by six μ2-MeCO2– , two terminal μ2-dbm– groups at the two ends of the molecule, and two MeOH molecules on the central Mn atoms. Intermolecular O…H–O hydrogen bonding interactions are found within the structure of the compound.  相似文献   

7.
A novel complex [Pb(qina)2(DMSO)]·H2O was synthesized,of which qina-is the quinaldic acid radical and DMSO the dimethyl sulfoxide. Elemental analysis,IR spectra,and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure. This complex belongs to monoclinic system,space group P121/n1,with a=7.1553(17),b=17.543(2),c=17.306(2) ,β=91.671(4)°,C22H20N2O6PbS,Mr=647.65,Z=4,V=2171.5(6) 3,Dc=1.981 g/cm3,μ=7.908 mm-1,F(000)=1248,–9≤h≤6,–23≤k≤19,–22≤l≤22,R=0.0221 and wR= 0.0488. Weak coordinate bond is formed between oxygen atom in DMSO and Pb(Ⅱ ) . There are also weak interactions,such as π-π interaction,hydrogen bonds and so on,among the complex molecules.  相似文献   

8.
1 INTRODUCTION As a rich remarkable class of inorganic cluster systems, polyoxometalates continue to be the focus of significant attention in the 21th century because of their various and alluring topologies as well as their unusual physicochemical prope…  相似文献   

9.
1 INTRODUCTION Exploration on the syntheses and properties of car- boxylate complexes, especially aromatic carboxylate complexes, has always been a fascinating and chal- lenging research field for decades either in coor- dination chemistry or in functional materials[1, 2]. Cy- anobenzoic acid (Hcba) possessing two functional coordination groups should display structural diver- sities on the formation of complexes[3~15]. In particu- lar, the copper(II) carboxylate complexes bearing spe- …  相似文献   

10.
A new mononuclear Co(II) complex, [Co(hmz)2(H2O)4]·2H2O, has been synthesized by the reaction of Co(CH3COO)2·4H2O with 1-(4-hydroxyphenyl)-5-mercaptotetrazole (Hhmz). It crystallizes in the monoclinic system, space group P21/n with a = 13.502(5), b = 6.718(3), c = 13.972(6) , β = 117.532(4)o, V = 1123.9(8) 3, Z = 2, M r = 553.45, F(000) = 570, Dc = 1.635 g/cm3, μ = 1.008 mm–1, the final R = 0.0272 and wR = 0.0684 for 2194 observed reflections (I > 2σ(I)). The Co(II) is six-coordinated by two nitrogen atoms from two hmz–1 ligands and four water molecules, forming an octahedral geometry. The intermolecular hydrogen bonding and offset-panel π-π stacking interactions between the adjacent molecules extend the compound into a three- dimensional supramolecular framework. The title compound emits strong blue fluorescent light (λem(max) = 427 nm) at room temperature and is red-shifted compared with free ligand Hhmz (λem(max) = 342 nm).  相似文献   

11.
用MnSO4H2O和哌嗪在水-甲醇混合溶剂中反应得到了1个超分子化合物[H2(C4H10N2)](SO4)(H2O) (C4H14N2O5S)。 该晶体属单斜晶系, 空间群为P21/n, 晶胞参数为: a = 6.386(1), b = 11.695(2), c = 11.680(2) ? = 101.06(3), V = 856.1(3) 3, Z = 4, Mr =202.23 , Dc = 1.569 g/cm3, F(000) = 432, ?= 0.368 mm-1。 该化合物是由[H2(C4H10N2)]2+、SO42-、H2O通过氢键自组装而形成的。 其中[H2(C4H10N2)]2+存在2种椅式构象:一种[H2(C4H10N2)]2+与4个SO42-、2个H2O通过氢键相连, 另一种[H2(C4H10N2)]2+则与6个SO42-相连。 它们分别沿着b、c方向交替排列展开, 通过SO42-桥联成二维的层状结构;层与层之间在NH…O、CH…O、OH…O氢键的作用下互相连接, 形成了具有网状结构的三维超分子化合物。 差热及热重测试表明:该化合物从92℃开始分解,首先失去1个H2O, 然后再失去[H2(C4H10N2)]2+和SO4 2-。  相似文献   

12.
1 INTRODUCTION In recent years, the rational design and synthesisof metal-directed supramolecular frameworks throughintermolecular hydrogen bonds, π-π stacking interac-tion or other weak interactions have received muchattention because of their interesting molecular topo-logies and various potential applications in catalysis,superconductor, magnetism, nonlinear optics, sen-sors and molecular recognition[1~4]. On the otherhand, the attachment of mono- or polypyridyl frag-ments to a ferr…  相似文献   

13.
Two hydrates of sodium 5,7‐dihydroxy‐6,4′‐dimethoxyisoflavone‐3′‐sulfonate ([Na(H2O)J(C17H13O6SO3)*2H2O,] 1) and nickel 5,7‐dihydroxy‐6,4′‐dimethoxyisoflavone‐3′‐sulfonate ([Ni(H2O)6](C17H13O6SO3)2*4H2O, 2) were synthesized and characterized by IR, 'H NMR and X‐ray diffraction analyses. The hydrate 1 crystallizes in the mono‐clinic system, space group P2(1) with a=0.8201(9) nm, b=0.8030(8) nm, c= 1.5361(16) nm, β=102.052(12)°, V =0.9893(18) nm3, D,= 1.579 g/cm3, Z=2, μ=0.252 nm?1, F(000)=488, R=0.0353, wR=0.0873. The hydrate 2 belongs to triclinic system, space group P‐1 with a=0.7411(3) nm, b=0.8333(3) nm, c=1.7448(7) nm, α= 86.361(6)°, β=86.389(5)°, γ= 88.999(3)°, V=1.0731(7) nm3, D,=1.587 g/cm3, Z=1, μ=0.649 m?1, F(000)= 534. In the structure of 1, the sodium cation is coordinated by six oxygen atom and two adjacent ones are bridged by three oxygen atoms to form an octahedron chain. The C? H…?… hydrogen bonds exist between two isoflavone molecules in the structure of 2. Meanwhile, hydrogen bonds in two compounds, link themselves to assemble two three‐dimensional network structures, respectively.  相似文献   

14.
以3-叠氮-1,2,4-三唑为配体,PA–(苦味酸根)或HTNR–(2,4,6-三硝基间苯二酚脱去一个羟基的质子后形成的离子)为外阴离子,制备得到了两种新的配合物:[Zn(AZT)4(H2O)2](PA)2∙4H2O和[Zn(AZT)2(H2O)4](HTNR)2∙4H2O。[Zn(AZT)4(H2O)2](PA)2∙ 4H2O的X射线晶体数据表明,中心Zn2+离子与来自4个AZT分子的N原子和2个H2O分子的O原子配位;而对于[Zn(AZT)2(H2O)4](HTNR)2∙4H2O来说,6个配位原子来自2个AZT分子的N原子和4个H2O分子的O原子。在两种配合物中,AZT配体分子的配位点都是三唑环上的4位N原子。H2O分子对于分子间氢键的形成起到了重要的作用,在分子间氢键的作用下形成了配合物的晶体结构。在[Zn(AZT)4(H2O)2](PA)2∙4H2O的晶体结构中,还存在错位面对面π-π堆积作用,它对于晶体结构的形成和稳定性也起到了重要作用。TG-DTG和DSC分析结果显示,[Zn(AZT)2(H2O)4](HTNR)2∙4H2O的热分解过程不如[Zn(AZT)4(H2O)2](PA)2∙4H2O剧烈,原因在于前者分子中含有较多配位水分子和较少AZT配体分子。感度测试结果表明,[Zn(AZT)4(H2O)2](PA)2∙4H2O有一定的火焰感度,而[Zn(AZT)2(H2O)4](HTNR)2∙4H2O却对热不敏感;两种化合物在撞击和摩擦作用下都表现钝感。  相似文献   

15.
The binuclear praseodymium(III) complex with N‐(1‐carboxyethylidene)‐salicylhydrazide (C10H10N2O4, H2L) was prepared in H2O‐C2H5OH mixed solution, and the crystal structure of [Pr2L2(HL)2(H2O)4]·3H2O·C6H6 was determined by X‐ray single crystal diffraction. The crystal complex crystallizes in the triclinic system with space group P‐1, and in the structure each Pr atom is 9‐coordinated by carboxyl O and acyl O and azomethine N atoms of two tridentate ligands to form two stable five‐membered rings sharing one side in keto‐mode and two water molecules. The coordination polyhedron around Pr3+ was described as a monocapped square antiprism geometry. In an individual molecule, four tridentate ligands were coordinated by two negative univalent (HL) and two bivalent forms (L) respectively. Two negative univalent ligands were coordinated via μ2‐bridging mode.  相似文献   

16.
Voltammetric behavior of sodium 7‐methoxyl‐4′‐hydroxylisoflavone‐3′‐sulfonate (SMHS) in the aqueous solution from pH 1 to 5 was studied by linear sweep voltammetry, cyclic voltammetry and normal pulse voltammetry. Experimental results showed that in 0.2 mol*L?1 sodium citrate‐hydrochloric acid buffer solution (pH=4.65), SMHS caused only one reduction wave at ?1.34 V (vs. saturated calomel electrode, SCE), which was an h‐reversible adsorptive wave of SMHS protonized involving one electron and one proton. The peak current of SMHS on linear sweep voltammogram was proportional to its concentration in the range of 8.0 × 10 ?8.0·10 mol*L?1 (r = 0.995). and the detection limit was 5.0·10?6mol*L?1. The method was applied to determination of SMHS, in synthetic samples. In addition, its scavenging effect on superoxide anion radical was studied by the auto‐oxidation of pyrogallol in HCI‐tris buffer solution (pH = 8.2) in order to explain its peculiar biological effects. The experimental results proved that SMHS has antioxidant quality, and it is an efficient free radical scavenger of superoxide anion radical.  相似文献   

17.
A new inorganic-organic hybrid supramolecular compound [Habo]6[V10O28]·solvents and its crystal structure was reported as follows: monoclinic, space group P21/n, a =11.419(9), b = 16.811(16), c = 15.521(12) (A), β= 102.98(2)°, V= 2903(4) (A)3, Z = 4, C15H46N3O19V5,Mr = 827.25, Dc = 1.893 g/cm3, λ(MoKα) = 0.71073 A,μ = 1.636 mm-1, F(000) = 1696, the final R =0.0696 and wR = 0.1361 for 4641 observed reflections with I > 2σ(I). The compound is based on decavanadate clusters [V 1oO28]6-. The hydrogen bonding interactions among Habo+ cations, solvents and decavanadate clusters extend 1 into a three-dimensional supramolecular architecture.  相似文献   

18.
孟祥茹  徐虹  潘彦  侯红卫 《结构化学》2003,22(3):359-362
采用水热法用Ni(NO3)26H2O和异烟酸制备出了一种新的由配合物形成的三维超分子体系—[Ni(C6H4O2N)2(H2O)4],并通过X射线衍射对其晶体结构进行了测定。 该晶体属三斜晶系,空间群为Pī, 所得晶胞参数为: a = 6.9228(4), b = 9.6664(19),c = 6.322(1) , a = 96.86(3), b = 113.33(3), g = 110.35(3)°, V = 347.6(1) 3, Z = 1, Mr = 374.98, Dc = 1.791 g/cm3, F(000) = 194, m = 1.443 mm-1。用1362个可观察的 (I > 2s(I))衍射点,修正123个结构参数, 最终偏离因子R = 0.0444,wR = 0.1271。在组成该化合物的基本结构单元[Ni(C6H4O2N)2(H2O)4]中,Ni处于1个稍微拉长的八面体的中心; 各个结构单元之间通过氢键OH…O相互连接,形成了无限伸展的具有层状结构的三维超分子体系。 另外,从差热及热重曲线可以看出,该化合物加热到154 ℃时开始分解, 首先失去4个H2O,再失去2个异烟酸根,最后残余物为NiO。  相似文献   

19.
Single crystals of Sr[B(C6H5O7)2](H2O)4 · 3H2O, a new borate‐citrate material, were grown with sizes up to 8 × 6 × 2 mm by slow evaporation of water at room temperature. The structure of Sr[B(C6H5O7)2](H2O)4 · 3H2O was determined by single‐crystal X‐ray diffraction. It crystallizes in the monoclinic space group P21/c, with a = 11.363(3) Å, b = 18.829(4) Å, c = 11.976(3) Å, β = 110.736(3)°, and Z = 4. The SrO8 dodecahedra, BO4 tetrahedra and citrate groups are linked together to form chains. The compound was characterized by IR and UV/Vis/NIR transmittance spectroscopy as well as thermal analysis.  相似文献   

20.
The title compound, {[Cu(2,2'-bipy)(C7H4O5S)(H2O)2](H2O}n (2,2'-bipy = 2,2'- bipyridine), was synthesized by the hydrothermal reaction of Cu(NO3)2(3H2O, 2,2'-bipyridine and 2-sulphobenzoic acid, and structurally characterized by single-crystal X-ray diffraction analysis. The crystal is of triclinic, space group P with a = 9.21(3), b = 10.17(3), c = 10.77(3) (A), α = 77.017(16), β = 89.80(8), γ = 68.46(7)°, V = 911(5) (A)3, Z = 2, (D/s)max = 0.001, Mr = 473.94, Dc = 1.728 g/cm3, μ(MoKα) = 1.365 mm-1, F(000) = 486, the final R = 0.0246 and wR = 0.0628 for 3809 observed reflections with I > 2σ(I). The mononuclear crystal structure extends into a two-dimensional net- work via hydrogen-bonding interactions and a three-dimensional framework is further formed by means of π-π stacking interactions.  相似文献   

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