Synthesis of propyl O-(α-L-rhamnopyranosyl)-(1→3)-[2,4-di-O-(2s-methylbutyryl)-α-L-rhamno-pyranosyl]-(1→2)-(3-O-acetyl-β-D-glucopyranosyl)-(1→2)-β-D-fucopyranoside,the tetrasaccharide moiety of Tricolorin A

Propyl O-(α-L-rhamncpyranosyl)-(1→3)-[2,4-di-O-(2s-methylbutyryl)-α-L-rham-nopyranosyl]-(1→2)-(3-O-acetyl-β-D-glucopyranosyl)-(1→2)-β-D-fucopyranoside (1), the tetrasac-charide moiety of Tricolorin A, was synthesized in total 23 steps with a longest linear sequence of 10 steps, and overall yield of 3.7% from D-Glucose. The isomerization of the dioxolane-type berzyli-dene in the presence of NIS/AgOTf was observed. Tetrasaccharide 1 exhibited no activity against the cultured P388 cell as Tricolorin A did.     

Asymmetric Hydrogenation Synthesis of (S)-(+)-2-(6′-methoxyl-2-naphthyl) propionic Acid by Cinchona Modified Pd(0)-α-FeOOH Catalyst

During the past decades enormous progress was made in asymmetric catalytic synthesis, an well-known example is BINAP1, the chiral hydrogenation synthesis of S-(+)-naproxen catalyzed by BINAP-Ru dicarboxylate complexes provides excellent enantioselectivity (up to 99% ee) and good chemical yield (92%), however the pressures is relatively high (135-150 atm) and the (S)-BINAP-Ru(III) complex is very expensive. This problem may present a practical limitation. In recent years new methodolo…     

RELEASE OF IBUPROFEN FROM PEG-PLLA ELECTROSPUN FIBERS CONTAINING POLY(ETHYLENE GLYCOL)-b-POLY(α-HYDROXY OCTANOIC ACID) AS AN ADDITIVE

<正>Poly(α-hydroxy octanoic acid) was first used as an additive for the preparation of electrospun ultra-fine fibers of poly(ethylene glycol)-b-poly(L-lactide)(PEG-PLLA).Ibuprofen was loaded in the electrospun ultra-fine fibers.The results from environmental scanning electron microscopy(ESEM),wide angle X-ray diffraction(WAXD) and differential scanning calorimetry(DSC) demonstrated that ibuprofen could be perfectly entrapped in the fibers electrospun from PEG-PLLA usingα-hydroxy octanoic acid or PEG-b-poly(α-hydroxy octanoic acid)(PEG-PHOA) as additives.Compared with electrospun PEG-PLLA fibers which entrapped 20 wt%ibuprofen,the PEG-PLLA electrospun fibers containing PEG-PHOA exhibited integral and robust after 1 week incubated in 37℃,pH 7.4 phosphate buffer solution with 10μg/mL proteinase K.Compared with electrospun fibers without PEG-PHOA,the concentration of proteinase K in release media had less effect on the release rate of ibuprofen.An unique release profile was found from PEG-PLLA fiber after the incorporation of PEG-PHOA. Enzyme degradation experiments demonstrated that PEG-PHOA but notα-hydroxy octanoic acid monomer was the crucial factor for integrity maintenance of the electrospun fibers,which may be due to the enzyme degradation tolerance property of the PEG-PHOA polymer additive.     

α-Ni(OH)2的研究进展

本文综述了α-Ni(OH)2在碱液中稳定存在的影响因素,对保持Ni(OH)2的alpha型结构所需条件及解决措施做了阐述;介绍了国内外α-Ni(OH)2电极的最新研究进展,着重叙述了Al3 、Mn3 和Zn2 替代Ni2 的α-Ni(OH)2的制备、稳定性和电化学性能以及尿素热分解制备的α-Ni(OH)2的特性;展望了纳米级α-Ni(OH)2的研究及应用前景.     

Synthesis, Crystal Structure and Characterization of α-(1-Benzimidazolyl)-hypnone Cobalt(Ⅱ) Complex:[CoCl(C7H5N2CH2COPh)4]Br

The crystal structure of [CoCl(C7H5N2CH2COPh)4]Br has been determined by means of X-ray crystallography. The molecular structure consists of a discrete [CoCl(C7H5N2CH2COPh)4] cation and one Br- anion. In the [CoCl(C7H5N2CH2COPh)4] cation, the coordination geometry of the central Co atom is square-pyramidal with four tertiary N atoms of benzimidazole from four α-(benzimidazol-1-yl)-hypnone ligands in the basal position and one chloride anion in the apical position. In the solid state, [CoCl(C7H5N2CH2COPh)4] and Br- anion possess intermolecular and intramolecular interactions, which stabilize the crystal structure. The characterization of the title compound were also carried out by using elemeutal analysis, FTIR, UV spectrometries and TG-DSC.     

Ag(Ⅰ)、Au(Ⅲ)、Pt(Ⅳ)离子与DNA相互作用的光谱研究

本文用中药小檗碱作为探针分子,在0.01mol·L^-1醋酸-醋酸钠缓冲体系中,用荧光和紫外-可见吸收光谱研究了贵金属离子Ag(Ⅰ)、Au(Ⅲ)、Pt(Ⅳ)与DNA的相互作用。在三种贵金属离子中,Au(Ⅲ)、Pt(Ⅳ)离子对小檗碱-DNA体系均具有明显的荧光猝灭作用,而Ag(Ⅰ)离子对该体系有强烈的荧光敏化作用。分别求出了三种贵金属离子与DNA的结合常数。三种贵金属离子与DNA结合能力的强弱顺序依次为:Au(Ⅲ) >Ag(Ⅰ) >Pt(Ⅳ)。探讨了三种贵金属离子与DNA的作用机理及导致结合力不同的原因。     

Ni_(x)Cu_(y)-B_(24)N_(28)催化CO_(2)氧化C_(3)H_(8)速控步骤的反应机理研究北大核心CSCD

采用密度泛函理论(DFT)研究了C_(3)H_(8)和CO_(2)在Ni_(x)Cu_(y)-B_(24)N_(28)(x+y=4,x=1、2、3、4)表面吸附及速控步骤反应机理.计算了C_(3)H_(8)、CO_(2)和相应中间体在Ni_(x)Cu_(y)-B_(24)N_(28)表面的吸附能以及6条可能路径下的反应热和活化能.计算结果表明,C_(3)H_(8)和CO_(2)在Ni_(x)Cu_(y)-B_(24)N_(28)表面是物理吸附,C_(3)H_(8)+CO_(2)→CH_(3)CHCH_(3)+OCOH是最有利的路径,其在不同催化剂表面的活化能顺序是NiCu_(3)-B_(24)N_(28)(1.42 eV)、Ni_(2)Cu_(2)-B_(24)N_(28)(1.57 eV)、Ni_(3)Cu-B_(24)N_(28)(1.62 eV)、Ni_(4)-B_(24)N_(28)(1.75 eV).由此可知,在Ni_(x)Cu_(y)-B_(24)N_(28)催化CO_(2)氧化C_(3)H_(8)的体系中,Cu含量直接影响其催化活性,即NiCu_(3)-B_(24)N_(28)用于催化CO_(2)氧化C_(3)H_(8)有一定优势.     

α-Ni(OH)_2的研究进展

本文综述了-αNi(OH)2在碱液中稳定存在的影响因素,对保持Ni(OH)2的alpha型结构所需条件及解决措施做了阐述;介绍了国内外-αNi(OH)2电极的最新研究进展,着重叙述了Al3+、Mn3+和Zn2+替代Ni2+的-αNi(OH)2的制备、稳定性和电化学性能以及尿素热分解制备的-αNi(OH)2的特性;展望了纳米级α-Ni(OH)2的研究及应用前景。     

金刚烷甲酸铜(Ⅱ)配合物Cu(ada)2(py)2(H2O)的合成和晶体结构

金刚烷甲酸铜(Ⅱ)配合物Cu(ada)2(py)2(H2O)的合成和晶体结构     

Pd(Ⅱ)的一种高选择性定性方法

试验发现，新试剂N-烯丙基-N'-(对苯磺酸钠)硫脲在氯化钠和2m01·L-1盐酸介质中与Pd(Ⅱ)生成黄色配合物。在此条件下，能与Pd(Ⅱ)共存的阳离子和阴离子正常温下均不产生沉淀或生成深色配合拘。N-烯丙基-N'(对苯磺酸钠)硫脲试法是Pd(Ⅱ)的一种高选择性鉴定方法。检出限为0．21μg，最低浓度为6．4Pg·m1-1。该方法条件容易控制，操作简便，在对实际样品中Pd(Ⅱ)的鉴定时，均获得满意结果。     

含酚氧桥的新型Cu(Ⅱ)-Mn(Ⅱ)和Cu(Ⅱ)-Co(Ⅱ)配合物的合成和磁性

合成了3种新型配合物[Cu(samen)Mn(NO_(2-)Phen)_2](1)、[Cu(sampn)Mn(NO_(2-)Phen)_2](2)和[Cu(samen)CO(terp)](3)(samen~(4-)、sampn~(4-)、NO_(2-)Phen和terp分别表示N,N′-乙二水杨酰胺根阴离子、N,N′-1,2-丙二水杨酰胺根阴离子、5-硝基-1,10-菲绕啉和联三吡啶),测得配合物的变温磁化率,求出交换积分,J分别为-63cm~(-1)(1)、—65cm~(-1)(2)和—7.68cm~(-1)(3),表明金属离子间有反铁磁超交换作用。     

Ru(Ⅲ)、Rh(Ⅲ)、Pd(Ⅱ)离子与ct-DNA的相互作用研究

本文以中药小檗碱作为分子探针，在0.01mol·L^-1醋酸-醋酸钠缓冲体系中，用紫外-可见吸收及荧光光谱法研究了Ru(Ⅲ)、Rh(Ⅲ)、Pd(Ⅱ)三种贵金属离子与DNA的键合相互作用。实验发现Ru(Ⅲ)离子对小檗碱-DNA二元体系的荧光有较强的猝灭作用;而Rh(Ⅲ)、Pd(Ⅱ)两种离子则对该二元体系产生显著的荧光敏化作用。考察了EDTA对贵金属离子、小檗碱及DNA三元混合体系的荧光光谱的影响，初步探讨了贵金属离子与DNA可能的键合机理。     

Synthesis and Characterization of Nickel(Ⅱ) and Copper(Ⅱ) Complexes with Schiff Base (1R,2R)-(-)-Diaminocyclohexane-N,N'-bis(3-tert-butyl-5-(4'-benzoic acid)-salicylidene)

Two homochiral metallosalen complexes,Ni(salen) (salen=(1R,2R)-(-)-diaminocyclohexane-N,N'-bis(3-tert-butyl-5-(4'-benzoic acid)-salicylidene) 1 and Cu(salen) 2,have been synthesized and characterized by IR,microanalysis,TGA,powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P2_12_12 with Z=4. For 1,α= 12.082(2),b = 15.447(3),c = 18.784(4)(A),V= 3505.7(12) (A)~3,M_r = 731.50,D_c = 1.386 g/cm~3,μ= 0.606 mm~(-1),F(000)=1544,the final GOOF=1.043,R=0.0496 and wR=0.1248 for 4791 observed reflections with Ⅰ> 2σ(Ⅰ). For 2,α=12.181(2),b=15.501(3),c=18.877(4)(A),V= 3564.3(12)(A)~3,M_r=736.33,Dc = 1.372 g/cm~3,μ=0.665 mm~(-1),F(000)=1548,the final GOOF= 1.062,R=0.0575 and wR=0.1508 for 4562 observed reflections with Ⅰ> 20(Ⅰ). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. An infinite two-dimensional network is generated by hydrogen bonding interactions and intermolecular π…π interactions.     

SYNTHESIS, SPECTRAL AND MAGNETIC CHARACTERISATION OF SOME BIMETALLIC ALKOXIDES OF NICKEL(Ⅱ)WITH GALLIUM(Ⅲ)AND ZIRCONIUM(IV)

Some interesting bimetallic isopropoxides of nickel(Ⅱ) with gallium(Ⅲ) and zirconium(Ⅳ), Ni[Ga(OPr~1)_4]_2 and Ni[Zr_2(OPr_1)_9]_2 have been synthesized by the interaction of NiCl_2·2Pr~1OH with K[Ga(OPr~1)_4],and K[Zr_2(OPr~1)_9] respectively, in 1:2 molar ratio. These bimetallic isopropoxides undergo facile alcohol interchange reactions with primary alcohols. However, reactions with tertiary alcohols result in the isolation of partially substituted derivatives with the compositions, Ni[Ga(OPr~1)(OBu~t)_3]_2 and Ni[Zr_2(OPr~1)_3(OBu~t)_6]_2. Characterisation of these derivatives has been made on the basis of elemental analyses, infrared, electronic spectral and magnetic susceptibility measurements. These studies suggest an octahedral geometry for nickel(Ⅱ) in the primary bimetallic alkoxides, while in the case of secondary and tertiary derivatives, an equilibrium is suggested between octahedral and tetrahedral forms.##属性不符     

Eu(OPri)3/Tb(OPri)3共掺杂P(MMA-co-St)

Eu(OPri)3/Tb(OPri)3共掺杂P(MMA-co-St);Eu(OPri)3/Tb(OPri)3;共掺杂;P(MMA-co-St);荧光性能     

Ru(phen)_3~(2+)-Ce(Ⅳ)化学发光体系检测吲哚乙酸的研究

基于吲哚乙酸(IAA)对三(1,10-菲咯啉)钌(Ⅱ)[Ru(phen)32+]-Ce(Ⅳ)化学发光体系的发光增强作用,建立了一种化学发光直接检测IAA的新方法。在优化的实验条件下,该方法的线性范围为5.0×10-3~2.0μg.mL-1,检出限为2×10-3μg.mL-1;对含0.50μg.mL-1IAA的溶液平行测定11次的相对标准偏差(RSD)为5.5%。方法用于合成样品中IAA含量的测定,结果满意。本文还对可能的化学发光机理进行了探讨。     

Two Eremophilane-type Sesquiterpenoids from the Rhizomes of Ligularia veitchiana（Hemsl.） Greenm

Two eremophilane-type sesquiterpenoids from the rhizomes of Ligularia veitchiana(Hemsl.) Greenm were isolated and determined as 10α,11-endoperoxide-1(2)-en-7α-hydroeremophilane(1) and 1(10)-en-2-oxo-7α-isopropanol-eremophilane(2).Compound 1 was a new compound and compound 2 was a new natural product.The structures of the two compounds were established by means of spectral methods including 1H NMR,13C NMR,2D NMR and MS.     

Ru(bipy)_3~(2 )/Ru(phen)_3~(2 )-C_2O_4~(2-)-Ce~(IV)化学发光反应动力学模型的研究

根据Ru(bipy)_3~(2 )/Ru(phen)_3~(2 )-C_2O_4~(2-)-Ce~Ⅳ(bipy=2,2＇-联吡啶,phen=1,10-邻菲咯琳)化学发光反应建立了该化学发光反应的动力学模型,根据模型计算出该反应的发光强度-反应时间曲线上升及下降阶段的反应速率常数、发光强度最大值及其出现的时间等.发光强度最大值及发光强度-反应时间曲线下的面积均可用于定量分析.     

Hydrothermal Synthesis and Crystal Structure of a Novel Dinuclear Co(Ⅱ) Complex: [Co2(2,2(')-bpy)2((-L)2(L)2(μ-H2O)] (HL = 4-Chlorobenzoic Acid)

A new 4-chlorobenzoic acid bridge Co(Ⅱ) complex [Co2(2,2(')-bpy)2(μ-L)2(L)2(μ- H2O)] (HL = 4-chlorobenzoic acid) has been obtained by hydrothermal synthesis, and X-ray single-crystal diffraction analysis shows that it crystallizes in the monoclinic system, space group C2/c with a = 22.537(5), b = 16.212(3),c = 15.306(3)(A), β= 124.37(3)°, V = 4616.1(16) (A)3, Mr = 1070.45, Dc = 1.540 g/cm3, Z = 4, μ = 1.012 mm-1, F(000) = 2176, the final R = 0.0338 and Wr = 0.0810. The title complex is composed of dinuclear [Co2(2,2(')-bpy)2(μ-L)2(L)2(μ-H2O)] molecules. Each Co(Ⅱ) atom is coordinated by two nitrogen atoms from one 2,2'-bipyridine ligand, three oxygen atoms from three 4-chlorobenzoic ions and another oxygen atom from one water molecule. The two Co(Ⅱ) atoms are connected by two 4-chlorobenzoic ions and one bridged water molecule. The dinuclear molecules are interlinked by hydrogen bond and π-π stacking interactions into a three-dimensional supramolecular network.     

Synthesis and Crystal Structure of a Copper(Ⅱ) Compound Constructed by N-(4,6-Dimethoxylpyrimidin)-N'-(ethoxycarbonyl)thiourea

A copper(Ⅱ ) complex Cu(L)2(NO3)2 constructed by the L (L = N-(4,6-dime- thoxylpyrimidin)-N'-(ethoxycarbonyl)thiourea) ligand crystallizes in monoclinic, space group C2/c with a = 16.2416(16), b = 9.1385(7), c = 22.0008(18) , β = 108.077(2)o, V = 3104.3(5)3, Dc = 1.627 g/cm3, Z = 4, C20H28CuN10O14S2, Mr = 760.18, μ(MoKα) = 0.920 mm–1, F(000) = 1564, R = 0.0471 and wR = 0.1284 for 2239 observed reflections (I > 2σ(I)). X-ray diffraction shows the existence of weak complementary intramolecular N–H…O (DA) hydrogen bonds which further strengthen the coordination from the two L ligands with the Cu(II) ion, intermolecular C–H…O hydrogen bonds and weak π…π stacking interactions, leading to the formation of a multi-dimen- sional supramolecular network.