雷酚萜醇的结构研究

雷酚萜醇属雷公藤二萜类化合物。雷公藤(Tripterygium wilfordii Hook f)系卫矛科(Celastraceae)雷公藤属植物。民间用于治疗风湿病、抗炎、抗肿瘤及抑制免疫系统等。     

全反式维甲酸合钇(Ⅲ)配合物对DNA的切割和键合作用(英)

以紫外光谱、荧光光谱、粘度法和凝胶电泳方法研究了全反式维甲酸合钇(Ⅲ)配合物与DNA的作用。结果表明，该配合物能在生理条件下比配体和金属离子更有效地切割质粒DNA，体系离子强度和pH值的变化对配合物的切割活性有较大影响，自由基捕捉剂的加入不影响配合物的切割活性。该配合物对DNA的切割可能通过水解机理进行。该配合物可使DNA的粘度增加，使EB-DNA体系的荧光强度和DNA溶液的紫外吸收强度降低。据此推断，该配合物主要以嵌入方式与DNA作用。     

一维链状冠醚配合物:[{Na(18-C-6)}2(H2O)]n[M(SCN)4]n(M=Pd、Pt)的合成与结构

The reactions of 18-crown-6 with Na₂[M(SCN)₄] (M= Pd,Pt) were studied and the complex 1 [{Na(18-C-6)}₂(H₂O)]_n[Pd(SCN)₄]_n and complex 2 [{Na(18-C-6)}₂(H₂O)]_n[Pt(SCN)₄]_n were characterized by ele-mental analysis, IR and X-ray diffraction analysis. The complexes belong to monoclinic, space group P2₁/n with cell dimensions, 1:a=1.05734(7),b=1.42250(10),c=1.47762(10) nm,β=107.5330(10)°,V=2.1192(2)nm³,Z=2,D_calcd=1.460g·cm^-3,F(000)=964,R₁=0.0406,wR₂=0.1264 and 2:a=1.05985(19),b=1.4237(3),c=1.4744(3) nm,β=107. 096(3)°, V=2.1264(7)nm³,Z=2,D_calcd=1.690g·cm^-3,F(000)=1028,R₁=0.0292,wR₂=0.0859. In the solid state, the complexes 1 and 2 show an one-dimensional chain of [{Na(18-C-6)}₂(H₂O)]²⁺ complex cations and [M(SCN)₄]^2- (M=Pd,Pt) complex anions bridged by Na-N in-teractions.     

两个具有混合卤素桥的闭式十二顶双镍十硼烷簇合物的合成与结构

研究了[NiX_2(PPh_3)_2](X = Br, I)在二氯甲烷等溶剂中与B_(10)H_(10)~ (2-)的反应，对形成的族合物[(μ-Br_(0.85)Cl_(0.15)-(Ph_2PC_6H_4)_2Ni_2B_ (10)H_6Cl(PPh_3)]·0.5CH_2Cl_2(1), [(μ-I_(0.1)Cl_(0.9)(Ph_2PC_6H_4) _2Ni_2B_(10)H_6Cl(PPh_3)]·0.25CH_2Cl_2(2)进行了元素分析、红外光谱、飞行 时间二次离子质谱和X射线单晶结构分析等表征。两个族合物均为闭式十二顶双镍 十硼烷，镍、镍之间还分别存在Cl, Br和Cl，I桥且Cl，Br或I的占有率不同。簇合 物还具有两个邻位环化的Ni-P-C-C-B五元环。研究结果进一步证实：阴离子对反应 产物有影响，二氯甲烷参与了反应。     

Studies on organo-phosphorus, -arsenic,and -antimony polytungstates and polymolybdates: V. Syntheses and structures of benzylarsonic polymolybdates

In order to investigate the influence of organic groups on the structural types of organoarsenic polymolybdates, benzylarsonic acid has been selected to react with sodium molybdate. Three new complexes have been synthesized and characterized: [C(NH₂)₃]₄ [(C₆H₅CH₂As)₂Mo₆O₂₄] (1), Cs₄[(C₆H₅CH₂AS)₂Mo₆O₂₄]·5H₂O ( 2 ) and [(n-C₄H₉)₄N]₃Na[(C₆H₅CH₂As)₂Mo₆O₂₄] · 6H_aO( 3 ). Molecular structure of compound 1 has been determined by means of single-crystal X-ray diffraction studies. It is monoclinic, space group P 2 ₁/n with cell dimensions of a = 12 . 342( 2 ), b = 18.621( 2 ), c = 10.042( 2 )Å, β = 105.80(1)°, V = 2220.5 ų, z = 2, μ = 15.854 cm^?1, R = 0.023. It is demonstrated that the structural types of benzylarsonic polymolybdates are the same as those for alkylarsonic polymolybdates but different from those for arylarsonic polymolybdates. Their elemental analyses, IR and UV spectra and electrochemical behaviors in aqueous solution have been reported. It is suggested that the arsenic—carbon bond has great influence on the structural types of organoarsenic polymolybdates.     

A comparative study of gold nanocubes, octahedra, and rhombic dodecahedra as highly sensitive SERS substrates

Gold nanocubes, octahedra, and rhombic dodecahedra with roughly two sets of particle sizes have been successfully synthesized via a seed-mediated growth approach. All six samples were analyzed for comparative surface-enhanced Raman scattering (SERS) activity. All of these Au nanostructures were found to yield strong enhancement at a thiophenol concentration of 10(-7) M and are excellent SERS substrates. Rhombic dodecahedra with a rhombus edge length of 32 nm showed significantly better enhancement than the other samples and can reach a detection limit of 10(-8) M. Simulations of the binding energies of thiophenol on the different faces of gold and electric near-field intensities of these nanocrystals have been performed to evaluate the experimental results. Superior SERS activity of these nanocrystals can be expected toward the detection of many other molecules.     

Cation-π Interactions:Synthesis and Crystal Structure of Complex:[Na(DB18C6)]2[Pd(SCN)4]

The cation-π interactions have attracted much attention as an important noncovalent binding force. We have synthesized and characterized the first example[K(DB 18C6)]₂[Pd(SCN)₄] which exist K⁺-π interactions in crown ether compounds^[1]. However,the reported Na+ complexes structurally characterized by X-ray diffraction analysis have so far been limited to a few compounds. We now report the structure of complex:[Na(DB18C6)]₂[Pd(SCN)₄] which also exist Na⁺-n interactions.     

A hybrid fuzzy integral decision-making model for locating manufacturing centers in China: A case study

This study presents a hybrid fuzzy integral decision-making model that integrates factor analysis, interpretive structural modeling, Markov chain, fuzzy integral and the simple additive weighted method for selecting locations of high-tech manufacturing centers in China. The analytical results of this case study demonstrate the feasibility of the proposed model for solving fuzzy multiple attribute decision-making problems, especially when criteria are interdependent. Further, the empirical study brings out some properties that are crucial for high-tech manufacturing centers to invest in China.     

Synthesis and Crystal Structure of {(PPh_3)_2CIRuCIRu(PPh_3) B_(10)H_8[OCH(CH_3)_2)]_2}

1INTRODUCTIONAlthoughseveralhundredpolyhedralmetallaboraneshavebeencharacterized,theincidenceofruthenaboranesisparticularlysurprising.(hThefirstpolyhedralruthenaboraneisstructurallytypifiedbythecompound[(PPh,)2RuB,,HS(OEt),j,whichisobtainedin40%yieldsfromthereactionbetweentRuCI,(PPh,),jandcloso-tB,,H,,j'--inCHCI,/EtOH.tZiWithCH,COOH/THFt'iandC,H,COOH/CH,CI,">insteadofCHCI,/EtOH,twocompoundsF{(PPh,)2Ru}~(p-MeCO,)3--(pH)z-{RuB,,H,}jand[(PPh,)2(PhCOO)RuB,,HSCljhav…     

Synthesis and Crystal Structure of {(PPh3)2ClRu(μ-Cl)-Ru(PPh3)B10H7[OCH(CH3)2]3}·0.4(H2O)

The title compound has been synthesized by the reaction of [RuCl2(PPh3)3] and closo-[B10H10]2- in (CH3)2CHOH solution. Crystals suitable for a single crystal X-ray diffraction analysis were obtained from n-pentane diffused to CH2Cl2 solution. The crystal {(PPh3)2ClRu(μ-Cl)Ru(PPh3)B10H7[OCH(CH3)2]3}·0.4(H2O) is monoclinic , space group P21/n , Mr=1359.47, with a=19.434(4), b =14.340(4), c=25.865(9)(A), β= 95.48(3)°, V=7175(4)(A)3, Dc=1.258 g/cm3, Z=4, λ(MoKα)=0.71073(A),μ=6.03 cm-1, F(000)=2784, R=0.0631, wR2= 0.1425, S=1.001. The title compound is a bimetallic species in which the second ruthenium center is bound to the cluster {(PPh3)RuB10H7[OCH(CH3)2]3} via an Ru-Cl-Ru and two Ru-H-B-Ru bridges. The third isoproxy group replaces a hydrogen atom on B(10) of the cage, which indicates the activity of the cage.