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1.
Taibaihenryiin C的构型、构象及晶体结构   总被引:1,自引:0,他引:1  
从太白山产的鄂西香茶菜中分离得到新骨架的二萜类化合物TaibaihenryiinC,对其进行X射线衍射晶体结构分析,确定其分子中各取代基的相对构型、环构象及晶体结构.研究表明,C-3位的羟基和C-11位的乙酰氧基以C-20位的甲基为参考均位于β位;分子中的A环为椅式构象,B,C环接近于船式构象,D环接近于信封式构象.特别是在D环中存在较大的扭转角,使D环中有内应力存在,这表明该化合物具有潜在的生理活性.TaibaihenryiinC的晶体结构属正交晶系,P212121空间群,晶胞参数a=0.6162(1)nm,b=1.2730(1)nm,c=2.5193(3)nm,Z=4.在晶体中分子间通过C-3位的-OH氢与C-11位的乙酰氧基上的羰基氧形成分子间氢键,使分子在晶体中沿a轴呈螺旋结构排列.  相似文献   

2.
唇形科香茶菜属植物溪黄草(Rabdosia serra(Maxim·)Hara)具有清热祛湿、凉血散瘀、抗肿瘤、抗菌、消炎及对肝脏的保护作用[1,2]。据文献报道,溪黄草中的对映-贝壳杉烷型二萜化合物,是其具有抗癌作用的主要功效成分[3-5]。其结构与冬凌草甲素极为相似,在同一波长处具有相似的紫  相似文献   

3.
本文报道首次将鄂西香茶菜甲素(3)用立体、区域和化学选择性的反应转变成冬凌草甲素(oridonin,1),7步反应总产率为9%.  相似文献   

4.
三种西藏香茶菜挥发油化学成分的研究   总被引:4,自引:1,他引:4  
唇形科植物香茶菜广泛分布于全国各地,民间一直用作抗菌消炎药使用,近年来发现,香茶菜属植物有抑制肿瘤和抗癌活性,其活性成分是二萜。我们对采自西藏的3种香茶菜的挥发油进行了GC/MS分析。从小叶香茶菜[Rabdosia Parrifolia(Batal)Hara; Litte leaf Rabdosia]油中分出84个峰,鉴定了27个,占总面积的60%;从川藏香茶菜(Rabbosia Pseudo-irrarata C.Y.Wu,Szechwan-Tibet Rabdosia)油中分出72个峰,鉴定了39个,占总面积的82.5%;从皱叶香茶菜[Rabdosia rugosa(Wcll.)Hara,Wrinkted leaf Rabdosia]中分出了90个峰,鉴定了39个,占总面积的62.1%。3种香茶菜的分析尚未见报道。  相似文献   

5.
将邻苯二胺、3-吡啶甲酸与二氯化镉在1:1的盐酸溶液中经水热反应,合成了一种超分子化合物[2-(3-pyridyl)benzimidazoleH2]24+·[Cd2Cl8]4-.通过元素分析、红外光谱、热重对其结构和性质进行了表征,用X-射线单晶衍射测定了该化合物的晶体结构.化合物晶体为单斜晶系,P21/c空间群.超分子化合物中的Cd2+与其周围4个氯离子配位,构成畸变三角锥构型的离子[CdCl4]2-,2个配阴离子[CdCl4]2-之间通过双氯桥键[Cd-Cl-Cd]构成五配位双核镉(Ⅱ)四元环状结构,并与2个2-(3-吡啶基)苯并咪唑两价阳离子,通过静电引力、氢键及π-π呵堆积作用形成三维网状超分子化合物.荧光测试表明该化合物具有较好的光致发光性能.  相似文献   

6.
Co(En)3MoO4晶体的水热合成与表征   总被引:1,自引:0,他引:1  
杂多酸的水热法合成的深入发展已引起了化学家的广泛关注[1~3].80年代已来,用水热合成方法得到了具有层状[4]、网状[5]、孔道状[6,7]和笼状[8,9]等多种新结构和新组成的杂多酸化合物,并应用于合成药物和研究催化剂等[10,11]工作中.科学家们已深入地了解了钒的氧簇化合物[12~15],但有关钼的氧簇化合物的研究还较少.杨国昱等[16]利用水热法合成了具有孔道结构的Ni(En)3MoO4纳米管.本文在此[16]基础上,利用水热法合成了具有网状结构的Co(En)3MoO4单晶.X射线分析结果表明,该晶体属六方晶系,P3C1空间群,晶体中阴阳离子通过静电吸引作用相互结合,形成一种有机-无机复合材料.  相似文献   

7.
新香茶菜素的结构   总被引:1,自引:0,他引:1  
从河南大别山地区产显脉叶香茶菜[Rabdosia nervosa(Hemsl.)C.Y.Wu et H.W.Li]叶的乙醚提取物中分离到三个二萜化合物,其中 odonicin 和显脉香茶菜素(nervosin)已报道,本文报道另一个新化合物,命名为新香茶菜素(neorabdosin,1)的结构研究.1为无色针状结晶,有微弱芳香气味,熔点230~232℃,[α]_D~(13)-175.5°(c 0.86,吡啶).经元素分析和质谱测定,其分子式为 C_(24)H_(30)O_7,M_r=430.48.IR:1735,1220(乙酰基),1720(六  相似文献   

8.
采用反应性熔盐法在550℃下合成一种新型混合价硒代锡酸盐晶体(K2Sn2Se4).该晶体属于四方晶系,空间群为I4cm,晶胞参数a=0.81524(12)nm,b=0.81524(12)nm,c=0.67152(13)nm.K2Sn2Se4晶体具有一维链状结构,一维的1∞[Sn2Se4]2-链沿c轴方向无限扩展,K+插入链之间.K2Sn2Se4属于Zintl型化合物,具有半导体特性.漫反射光谱法研究结果表明,该化合物的光学能隙(Eg)为1.7eV.  相似文献   

9.
合成了砷钼夹心型化合物Na5[ (CH3)4N]3( H3O)2[ Co2( AsVMo9O33)2]·8H2O,用X-射线单晶衍射、元素分析和红外光谱对晶体的结构进行了表征.结构表征指出该化合物是由砷钼夹心型[ Co2(AsVMo9O33)2]10-多阴离子,( CH3 )4N+反荷阳离子,Na+反荷阳离子和结晶水分...  相似文献   

10.
采用水热合成方法制备出了1个12-钒钨酸基咪唑杂化化合物(C3H5N2)4[VW12O40]·1.25H2O,并用IR、UV和X射线单晶衍射技术对其结构进行了表征.结构解析结果表明,该晶体属于三斜晶系,空间群为P1-,它是由[VW12O40]4-簇阴离子,质子化的咪唑和结晶水组成.将标题化合物制成碳糊电极,利用循环伏安法研究了其电化学行为及其对NO2-还原的电催化性能;以罗丹明B为模拟物,探究了该化合物的光催化活性.结果表明,用标题化合物修饰的碳糊电极对NO2-的还原具有良好的电催化效果;标题化合物作为光催化剂在降解罗丹明B反应中具有良好的可见光催化活性.  相似文献   

11.
Two new oxo-centered trinuclear iron complexes [Fe3(μ3-O)(μ-O2CEt)6(H2O)3]Cl.3H2O 1 and [Fe3(μ3-O)(μ-O2CEt)6Py3]Cl 2 were prepared in non-aqueous solvent and their crystal structures have been determined. Crystal 1 is monoclinic, space group P21/n, a=9.909(3), b=24.467(8), c=14.542(7)(), β=107.85(4)° V=3356(4)()3, Z=4, Mr=765.52, Dc=1.52 g/cm3, μ=14.28 cm-1, F(000)=1588 and R=0.059, Rw=0.071 for 3745 unique reflections with I>3σ(I). Crystal 2 belongs to the monoclinic system with space group C2/c, a=13.750(3), b=18.439(4), c=16.696(3)(), β=93.42(3)°, V=4226(3)()3, Z=4, Mr=894.73, Dc=1.41 g/cm3, μ=11.4 cm-1, F(000)=2322 and R=0.058, Rw=0.062 for 2272 unique reflections with I>3σ(I). The two structures contain the same trimetal framework in which three iron(Ⅲ) atoms form a nearly equilateral triangle with a μ3-oxygen atom in the centre.  相似文献   

12.
1INTRODUCTIONTrinuclearoxo centeredmetalcarboxylateasembliesofthegeneralcomposition〔M3(μ3 O)(μ2 O2CR)6(L)3〕n+havebenofintense...  相似文献   

13.
翁华森  林平  杜少武 《结构化学》2009,28(6):752-760
Three new cadmium or zinc arenedisulfonate complexes [Zn(bpp)2(L)]n 1, { [Cd(bpp)2(1,5-NDS)(H2O)2]·4H2O }n 2 and { [Cd(bpp)2(H2O2)2]·(1,5-NDS) } n 3 (L = 4,4′-bis(2-sulfonatostyryl)biphenyl, bpp = 1,3-di(4-pyd-dyl)propane and 1,5-NDS = 1,5-Naphthalenedisulfonate) have been synthesized from aqueous solution and structurally characterized by infrared spectroscopy, elemental analysis and single-crystal X-ray diffraction. Crystal data for complex 1: space group P21/n, a = 10.559(3), b = 13.138(4), c = 17.623(5)A^°, β = 100.852(3)°, V = 2400.9(12) A^°^3 Z = 2, Dc= 1.351 g/cm^3, F(000) = 1016, μ = 0.654 mm^-1, the final R = 0.0412 and wR = 0.0994; Crystal data for complex 2: space group P^-1, a = 8.5642(19), b = 10.076(3), c = 12.114(3) A^°, α = 81.623(7), β = 77.149(8), γ = 82.787(7)°, V = 1003.6(4) A^°^3 Z = 1, Dc= 1.495 g/cm^3, F(000) = 466,μ = 0.713 mm^3, the final R = 0.0241 and wR = 0.0713; Crystal data for complex 3: space group C2/c, a = 21.6024(15), b = 9.4608(5), c = 18.4656(11)A^°, β = 107.359(3)°, V= 3602.0(4)A^°^3 Z = 4, Dc= 1.533 g/cm^3, F(000) = 1704,μ = 0.780 mm^-1, the final R = 0.0229 and wR = 0.0572. The X-ray single diffraction reveals that 1 exhibits a 3D metal-organic framework formed from 2D Zn(bpp)2^2+ networks connected by L in the third dimension; 2 and 3 possess 3D and 2D architectures constructed from 1D polymeric chains through H-bond. Complexes 1-3 display photoluminescent emissions at 452 and 335 nm, respectively.  相似文献   

14.
1 INTRODUCTION Recent years have seen a drastic increase of compounds containing the Mo3S4 core. A major synthetic route to these compounds is by the reaction of the aqua ion [Mo3S4(H2O)9]4+ with different kinds of ligands replacing some or all of the water molecules. In this way, Mo3S4(dtp)4(H2O), which was synthesized by the spontaneous- assembly method in 1986[1] and its structural characterization and chemical reactivity have been well recognized [2], can be rationally synthesize…  相似文献   

15.
1 INTRODUCTION In the past decade or so far, the construction of extended multidimensional coordination polymers comprised of metal ions as nodes and bridged ligand as linkers or spacers of self-assembly has attracted considerable attention in supramolecular and materi- als chemistry due to the formation of the intriguing topological structures and potential applications as functional materials[1~4]. In construction of these ex- tended structures, selection of the polydentate orga- nic li…  相似文献   

16.
We present here the first examples of lanthanide ion complexes with only isophthalic acid or thiophenylisophthalic acid ligands. The complexes of isophthalic acid with Eu(3+) (1) and Tb(3+) (2) and the moderately soluble complexes of 5-thiophen-3-ylisophthalate with Eu(3+) (3), Gd(3+) (4), and Tb(3+) (5) were isolated as single crystals through gel crystallization. X-ray diffraction studies confirm the cross-linking structure of these complexes, which, in case of the thiophenyl derivatives, results in low solubility in common solvents. The two-dimensional isophthalato complex of Eu(3+) (1) crystallizes in the C2/c space group, with a = 22.154(4), b = 12.649(3), and c = 15.921(3) A, beta = 112.34(3) degrees, and V = 4126.7(14) A(3), while the one-dimensional Tb(3+) complex of the same ligand, 2, crystallizes in the space group P2(1)/c with a = 11.921(2), b = 10.838(2), and c = 17.499(4) A, beta = 92.44(3) degrees, and V = 2258.9(8) A(3). The thiophenylisophthalato complexes of Eu(3+) (3) and Gd(3+) (4) are two-dimensional and crystallize in the P2/n space group with parameters for 3 of a = 14.139(3), b = 10.684(2), and c = 15.138(3) A, beta = 102.51(3) degrees, and V = 2232.3(8) A(3) and parameters for 4 of a = 14.1195(13), b = 10.6594(10), and c = 15.1149(14) A, beta = 102.529(2) degrees, and V = 2220.7(4) A(3), while the Tb(3+) complex, 5, also two-dimensional, crystallizes in the P space group with a = 11.051(2), b = 14.528(3), and c = 15.041(3) A, alpha = 77.63(3), beta = 87.86(3), and gamma = 83.51(3) degrees, and V = 2343.48 A(3). All complexes of Eu(3+) and Tb(3+) luminesce in aqueous solution, and the luminescence lifetimes and quantum yields are 123.8 +/- 7.4, 0.14% (1), 475.1 +/- 14.5, 3.58% (3), 129.3 +/- 3.5, 0.19% (4), and 213.9 +/- 2.2 micros, 7.46% (5).  相似文献   

17.
The stabilization of unsupported Ti-M (M = Fe, Ru, Co) heterodinuclear complexes has been achieved by use of amidotitanium building blocks containing tripodal amido ligands. Salt metathesis of H(3)CC(CH(2)NSiMe(3))(3)TiX (1) and C(6)H(5)C(CH(2)NSiMe(3))(3)TiX (2) as well as HC{SiMe(2)N(4-CH(3)C(6)H(4))}(3)TiX (3) (X = Cl, a; Br, b) with K[M(CO)(2)Cp] (M = Fe, Ru) and Na[Co(CO)(3)(PR(3))] (R = Ph, Tol) gave the corresponding stable heterobimetallic complexes of which H(3)CC(CH(2)NSiMe(3))(3)Ti-M(CO)(2)Cp (M = Fe, 6; Ru, 7) and HC{SiMe(2)N(4-CH(3)C(6)H(4))}(3)Ti-M(CO)(2)Cp (M = Fe, 12; Ru, 13) have been characterized by X-ray crystallography. 6: monoclinic, P2(1)/n, a = 15.496(3) ?, b = 12.983(3) ?, c = 29.219(3) ?, beta = 104.52(2) degrees, Z = 8, V = 5690.71 ?(3), R = 0.070. 7: monoclinic, P2(1)/c, a = 12.977(3) ?, b = 12.084(3) ?, c = 18.217(3) ?, beta = 91.33(2) degrees, Z = 4, V = 2855.91 ?(3), R = 0.048. 12: monoclinic, I2/c, a = 24.660(4) ?, b = 15.452(3) ?, c = 20.631(4) ?, beta = 103.64(3) degrees, Z = 8, V = 7639.65 ?(3), R = 0.079. 13: monoclinic, I2/c, a = 24.473(3) ?, b = 15.417(3) ?, c = 20.783(4) ?, beta = 104.20(2) degrees, Z = 8, V = 7601.84 ?(3), R = 0.066. (1)H- and (13)C-NMR studies in solution indicate free internal rotation of the molecular fragments around the Ti-M bonds. Fenske-Hall calculations performed on the idealized system HC(CH(2)NH)(3)Ti-Fe(CO)(2)Cp (6x) have revealed a significant degree of pi-donor-acceptor interaction between the two metal fragments reinforcing the Ti-Fe sigma-bond. Due to the availability of energetically low-lying pi-acceptor orbitals at the Ti center this partial multiple bonding is more pronounced that in the tin analogue HC(CH(2)NH)(3)Sn-Fe(CO)(2)Cp (15x) in which an N-Sn sigma-orbital may act as pi-acceptor orbital.  相似文献   

18.
Three new inorganic-organic composite polyoxotungstates [Cu(2,2'- bpy)2]5[α- PW11.5Cu0.5O40]·2H2O 1, [Co(2,2'-bp3)2(N3)2]4H3[α-PW12O40]·3H2O 2 and [Cu(2,2'-bpy)2(4,4'- bpy)]2[α-GeW12O40].4H2O 3 (2,2'-bpy = 2,2'-bipyridine, 4,4'-bpy = 4,4'-bipyridine) have been hydrothermally synthesized and structurally characterized. 1 crystallizes in the orthorhombie space group Pna21 with α = 27.847(3), b = 21.597(2), c = 20.1179(19) A, V = 12099(2) A3, Z = 4, GOF= 1.038, R = 0.0427 and wR = 0.1035; 2 belongs to the triclinic space group P1 with a= 12.31150(10), b = 16.1954(4), c = 19.36290(10) A, α = 99.366(11), β=105.168(8),γ = 111.836(8)°, V = 3309.98(9) A3, Z = 1, GOF = 1.024, R = 0.0739 and wR = 0.2216; and 3 crystallizes in the monoclinic space group P21/n with a = 12.858(4), b = 20.943(6), c = 15.598(5) A, β = 102.338(5)°, V = 4103(2) A3, Z = 2, GOF = 1.026, R = 0.0557 and wR = 0.1316. The common structural features of 1~3 are that their molecular structures all consist of a saturated a-Keggin polyoxoanion and several discrete metal-organic moieties. Intriguingly, 2 and 3 are composed of metal-organic coordination moieties with two mixed ligands.  相似文献   

19.
In our pursuit of luminescent lanthanide ion-based coordination polymers, we have isolated several complexes with nitrobenzoic acid ligands and characterized these by X-ray crystallography and luminescence spectroscopy. 2-Nitrobenzoic acid reacts with Eu(III) to form 1, which crystallizes in the P-1 space group, with a = 12.385(3), b = 12.912(3), c = 17.889(4) A, alpha = 97.49(3), beta = 109.64(3) and gamma = 101.99(3) degrees . 3-Nitrobenzoic acid forms a one-dimensional coordination polymer with Eu(III), 2, which crystallizes in the triclinic space group P-1 with a = 9.7100(19), b = 10.579(2), c = 13.361(3) A, alpha = 77.41(3), beta = 88.78(3) and gamma = 88.16(3) degrees. Structures 3 and 4 correspond to the isostructural one-dimensional coordination polymers of Eu(III) and Tb(III), respectively, with the 4-nitrobenzoato anion. These crystallize in the triclinic space group P-1 with a = 9.2242(18), b = 15.102(3), c = 18.587(4) A, alpha = 75.93(3), beta = 82.88(3) and gamma = 79.00(3) degrees for 3 and a = 9.2692(19), b = 15.369(3), c = 18.353(4) A, alpha = 75.37(3), beta = 81.32(3) and gamma = 78.15(3) degrees for 4. Potentiometry, absorption and NMR spectroscopy indicate that in solution only 1 : 1 species are present. All compounds are weakly luminescent as solids and the photophysics of solutions of ligands with Ln(III) in 1 : 1 stoichiometry were studied. Quantum yields around 1 and 3% for Eu(III)-and Tb(III)-containing methanolic solutions were measured.  相似文献   

20.
Two silver(I) complexes were prepared by the reaction of [Ag(C(CPh)]n with NP3 [NP3 = N(CH2CH2PPh2)3] or with NP3 and [Cu(CH3CN)4]ClO4. Complex 1 [(Ag2Cl(NP3)2)(Ag5(C(CPh)6)] contains both NP3 and PhC(C- ligands. The complex cation is (Ag2Cl(NP3)2)+, in which two Ag(NP3)+ cations were bridged by a Cl- donor. The anion is (Ag5(C(CPh)6)-, where five Ag+ ions are linked by six C(CPh- to form a pentanuclear cluster. Complex 2 only contains NP3 ligand, where the silver center adopts a trigonal-bipyramidal geometry. Crystal data for 1: C133H116Ag7Cl3N2P6, Mr = 2789.54, triclinic, space group P, a = 13.0780(2), b = 15.3678(2), c = 31.2041(3) (A), α = 91.3928(7), β = 90.9328(8), γ = 96.0244(4)o, V = 6233.8(1) (A)3, T = 293(2) K, Z = 2, Dc = 1.486 g/cm3, F(000) = 2796, μ = 1.266 mm-1, the final R = 0.0746 and wR = 0.1953 for 16475 observed reflections with I > 2σ(I). Crystal data for 2: C42H42AgClNO4P3, Mr = 861.00, trigonal, space group R3, a = 17.451(1), b = 17.451(1), c = 11.3985(7) (A), V = 3006.0(3) (A)3, T = 293(2) K, Z = 3, Dc = 1.427 g/cm3, F(000) = 1326, μ = 0.731 mm-1, the final R = 0.0251 and wR = 0.0663 for 1499 observed reflections with I > 2σ(I).  相似文献   

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