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1.
王孝伟  张志丽  刘杰  马小艳  刘俊义 《有机化学》2004,24(10):1271-1273
报道了1,3-二苄基-6-(3,4-环氧丁基)尿嘧啶的合成新方法.以6-甲基尿嘧啶(1)为起始物,经1,3-二苄基-6-甲基尿嘧啶(2)及未见文献报道的1,3-二苄基-6-(3-丁烯基)尿嘧啶(3)和1,3-二苄基-6-(3-羟基-4-溴丁基)尿嘧啶(4),首次高收率合成了1,3-二苄基-6-(3,4-环氧丁基)尿嘧啶(5),并对其化学结构进行了表征.  相似文献   

2.
以四-(4-甲氧基-3-磺酸基苯)卟啉(T(4-Mop)PS4)为探针,通过T(4-Mop)PS4与牛血清白蛋白(BSA)的相互作用,建立了测定BSA的电化学分析方法。T(4-Mop)PS4的峰电流变化(ΔIp)与BSA在2.0×10-6~1.0×10-5mol.L-1范围内呈良好的线性关系,检出限为1.2×10-6mol.L-1;对5.0×10-6mol.L-1BSA平行测定8次,其相对标准偏差为2.0%,回收率为95%~104%。组氨酸、缬氨酸、苯丙氨酸、丝氨酸、异白氨酸、谷氨酰胺、苏氨酸等氨基酸对BSA的测定不产生干扰。采用紫外可见光度法、荧光光谱法和线性扫描伏安法(LSV)研究了T(4-Mop)PS4与BSA之间的相互作用,并测定了二者相互作用的结合常数和结合比。研究表明,T(4-Mop)PS4与BSA之间主要以疏水作用力结合,形成了1∶1的稳定复合物。  相似文献   

3.
You J  Sheng X  Ding C  Sun Z  Suo Y  Wang H  Li Y 《Analytica chimica acta》2008,609(1):66-75
Surface plasmon resonance (SPR) was used to screen the interaction between a variety of affinity ligands and hemagglutinin (HA) from human influenza virus, with the aim of identifying low affinity ligands useful for the development of a rapid bioanalytical sensor. Three sialic acid-based structures and four lectins were evaluated as sensor ligands. The sialic acid-based ligands included a natural sialic acid-containing glycoprotein, human alpha1-acid glycoprotein (alpha1-AGP), and two synthetic 6'-sialyllactose-conjugates, with varying degree of substitution. The interaction of HA with the four lectin-based ligands, concanavalin A (Con A), wheat germ agglutinin (WGA), Maackia amurensis lectin (MAL), and Sambucus nigra agglutinin (SNA), showed a wide variation of affinity strengths. Affinity and kinetics data were estimated. Strong affinities were observed for Con A, WGA, alpha1-AGP, and a 6'-sialyllactose-conjugate with a high substitution degree, and low affinities were observed for MAL and a 6'-sialyllactose-conjugate with low substitution. The main objective, to identify a low affinity ligand which could be used for on-line monitoring and product quantification, was met by a 6'-sialyllactose-ovalbumin conjugate that had 0.6 mol ligand per mol carrier protein. The apparent affinity of this ligand was estimated to be 1.5+/-0.03 microM (K(D)) on the SPR surface. Vaccine process samples containing HA were analyzed in the range 10-100 microg HA mL(-1) and correlated with single-radial immunodiffusion. The coefficient of variation on the same chip was between 0.010 and 0.091.  相似文献   

4.
氧氟沙星(ofloxacin,OFL)又名氟嗪酸,是第3代喹诺酮类药物,通过作用于细胞DNA螺旋酶的A亚单位,抑制DNA的合成和复制导致细菌死亡,具有高效广谱抗菌作用,是治疗呼吸道、泌尿道、肠道、皮肤、关节及软组织等感染的有效药物,而大剂量的服用可发生结晶尿,若不调整剂量,会使肝、肾功能减退、血药浓度增高等,因此测定药物中OFL的含量有重要意义.  相似文献   

5.
该文制备了纳米金-离子液体修饰电极(GNP-[BMIM]PF6/GCE),用红外光谱对GNP和[BMIM]PF6进行了表征.采用交流阻抗法研究了GNP-[BMIM]PF6/GCE的表面电化学特性,同时研究了双酚A(BPA)在该修饰电极上的循环伏安行为.结果表明,BPA在该修饰电极上出现1个氧化峰,无还原峰,为不可逆电化...  相似文献   

6.
Crystal Structure of Tl4Fe(CN)6 Single crystals of Tl4Fe(CN)6 have been prepared for the first time and its crystal structure was determined. The pale yellow compound crystallizes in the triclinic space group P1 (No. 2) with the lattice parameters a = 726.6(1) pm, b = 797.4(8) pm, c = 1 336.0(1) pm, α = 104.7(9)°, β = 90.0(8)°, γ = 97.6(7)°, Z = 2 in a new structure type.  相似文献   

7.
应用低热固相合成法制备锂离子电池正极材料L iCo1/3N i1/3Mn1/3O2.研究该材料的结构与形貌,并比较它在商品L iPF6盐和在实验室合成的L iBOB(L iB(C2O4)2)盐电解液中的电化学性能.在L iPF6/EC+DMC+DEC电解液中,该材料表现出优良的电化学性能,其于0.5C、1C、1.5C、2C、3C放电倍率的初始比容量依次为167、163、163、157、147mAh/g,电池的循环性能也较好,说明低热固相合成的材料的有较好的高倍率性能.在L iBOB/EC+DEC+DE电解液中,0.5C倍率下比容量为160 mAh/g,较之L iPF6盐电解液的相差不大,但在高倍率下的比容量有所下降.  相似文献   

8.
A Cytotoxic Saponin with Two Monoterpenoids from Albizia julibrissin   总被引:1,自引:0,他引:1  
The dried stem barks of Albl'ziajulibrissin have been specified in Chinese Pharmacopeiaas a sedative agent. In the previous research several novel saponins were reported'-'.T.Ikeda. at al' isolated three similar saponins almost at the same time. In our further studieson the 95O/O etllanol extract from the plant, a new saponin I was obtained. This paper'involves the isolation and structural elucidation of the new saponin.Air-dried powdered stem barks (13.5 kg.) were extracted with 95% ethan…  相似文献   

9.
佘剑楠  徐抗震  张航  黄洁  赵凤起  宋纪蓉 《化学学报》2009,67(23):2645-2649
利用1-氨基-1-肼基-2,2-二硝基乙烯(AHDNE)和亚硝酸钾在酸性水溶液中合成出了高能富氮化合物1,4-二氢- 5H-(二硝基亚甲基)-四唑(DNMT), 并在水溶液中培养出DNMT•2H2O单晶. 该晶体属正交晶系, 空间群为Pnma, 晶胞参数为: a=10.392(2) Å, b=15.809(4) Å, c=5.0640(11) Å, V=832.0(3) Å3, Dc=1.629 g•cm-3, μ=0.163 mm-1, F(000)=432, Z=4, R1=0.0311, wR2=0.0885. 运用Gaussian 03程序, 在6-311++G**基组水平上, 用HF和B3LYP两种方法对DNMT分子进行了几何全优化和相应的电荷、轨道能量分析. 理论计算和热分析结果表明DNMT呈现较差的热稳定性.  相似文献   

10.
通过葫芦[6]脲(CB[6])与聚[4乙烯基溴(N正丁基)吡啶季铵盐](P4VBuBr,2)在水溶液中于室温下进行超分子自组装,得到一类超分子聚合物———准聚轮烷.通过1HNMR、IR、元素分析对其结构进行了表征,证实CB[6]位于2的侧基脂肪链上,通过非共价键与2结合,并且CB[6]与2重复单元的结合摩尔比分别为0.28∶1、0.2∶1、0.1∶1;通过X射线粉末衍射(XRD)、热重分析(TGA)、紫外可见吸收(UVVis)对其性质进行了研究,证实了准聚轮烷比相应的聚合物2有更高的热稳定性、更强的UVVis吸收以及较高的结晶能力;热分解温度随着准轮烷中CB[6]含量的增加而逐渐提高;NaBr是准聚轮烷的优良的沉淀剂.  相似文献   

11.
The silver iodate(VII), Ag5IO6, was obtained by reacting a stoichiometric mixture of Ag2O and KIO3, at elevated oxygen pressure, adding a small portion of distilled water. The synthesis was done at 673 K and 270 MPa of oxygen pressure. The crystal structure was solved by direct methods based on single crystal diffraction data ( , Z = 6, a = 5.9366(1), c = 32.1471(6) Å, 323 independent reflections, R1 = 2.31 %). According to conductivity measurements, Ag5IO6 is semiconducting with a specific resistance of 0.08 Ωcm at 300 K. The activation energy was determined as 7.4(1) meV in the temperature range of 220 – 300 K, and 4.3(1) meV in the temperature range of 90 – 180 K. The optical band gap for Ag5IO6 is 1.4 eV. Ag5IO6 is diamagnetic with a magnetic susceptibility of ?4.4×10?4 emu/mol.  相似文献   

12.
Silver(I)-diphosphine complex is an effective catalyst for Mukaiyama Aldol reaction in polar solvents. AgPF6-(S)-BINAP cationic chiral complex indicated a good activity and could afford fairly high enantioselectivity in the reaction of aromatic aldehydes and silyl enol ethers. On the other hand, AgOAc-(S)-BINAP system afforded the aldol product of the absolute configuration opposite to that by AgPF6-(S)-BINAP and very high catalytic activity was shown. The structure and equilibrium state of Ag(I)-BINAP complexes in solution were examined to understand the reaction mechanism. In AgPF6 system [Ag((S)-BINAP)2]PF6 (1a), [Ag((S)-BINAP)]PF6 (1b), [Ag2((S)-BINAP)](PF6)2 (1c) and AgPF6 are present in solution. The active species of the aldol reaction in DMF is [Ag((S)-BINAP)]PF6 (1b), which exists as a minor species in solution. For this cationic Ag(I) catalyst, cyclic transition state containing substrate and silyl enol ether is assumed. In AgOAc-(S)-BINAP system, active species is also monomeric AgOAc((S)-BINAP) (2b) species which exists as a major component in solution and strong interaction was observed with a silyl enol ether. The reaction by AgOAc-(S)-BINAP catalyst is concluded to proceed as follows: nucleophile forms a complex with AgOAc-(S)-BINAP species and is activated. This complex attacks aldehydes to afford aldol adduct via acyclic transition state.  相似文献   

13.
The different interactions between a chemosensor,1-(naphthalen-2-yl)-3-(6-nitrobenzothiazol-2-yl)-thiourea(1),and F-,acetate(AcO-),Cl-,and Br-anions have been investigated theoretically at the B3LYP/6-31+G(d,p) level with the basis set superposition error(BSSE) correction.It was found that the high selectivity of compound 1 for F-can be ascribed to the ability of the anion to deprotonate the N-H fragment of the host sensor,while the chemosensor also has a strong affinity for AcO-by virtue of the formation of a hydrogen-bonded complex.Intramolecular charge transfer(ICT) causes the colorimetric signaling of compound 1 after interaction with F-/AcO-.A study of substituent effects suggested that the O/NH-and O/S-substituted derivatives are also expected to be promising candidates for chromogenic F-/AcO-chemosensors.  相似文献   

14.
采用饱和蒸气扩散技术,将2,4-二羟基苯甲醛缩异烟酰腙(H_2dhbi)配体分别与Zn(ClO_4)2·6H_2O和Zn(NO_3)_2·6H_2O进行配位作用,得到2种不同配位模式的金属-有机框架材料[(dhbi)_2Zn_2·8H_2O]n(1)和{[(dhbi)_2(H_2O)_2Zn_2]·4DMF]}n(2).利用X射线单晶衍射、热分析技术(TG-DTA)和X射线粉末衍射(PXRD)等方法进行了结构表征.进一步将配位聚合物1和2用于对甲醇分子的吸附性能研究,结果表明,化合物1是一种理想的微孔材料,其对甲醇分子的吸附能力为化合物2的近5倍,采用PLATON对材料的孔隙体积进行计算得到化合物1和2的孔隙率分别为38.2%和5.5%.  相似文献   

15.
Atom transfer radical polymerization using activators regenerated by electron transfer (ARGET ATRP) of acrylonitrile (AN) was first approached with 1‐(1‐ethoxycarbonylethyl)‐3‐methylimidazolium tetrafluoroborate ([ecemim][BF4]) as reaction medium and tin(II) bis(2‐ethylhexanoate) (Sn(EH)2) as reducing agent in the presence of air. When compared with in bulk, an obvious increase of polymer isotacticity was observed for ARGET ATRP of AN in 1‐(1‐ethoxycarbonylethyl)‐3‐methylimidazolium hexafluorophospate ([ecemim][PF6]), the reaction rate of ARGET ATRP of AN in [ecemim][PF6] was higher and the polymerization process was better controlled. The block copolymer polyacrylonitrile‐block‐poly(methyl methacrylate) with molecular weight at 69,750, distribution at 1.34, and isotacticity at 0.36 was successfully obtained in [ecemim][PF6]. [Ecemim][PF6] and the catalyst system were recycled and reused and had no effect on the living nature of polymerization. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

16.
合成了分化诱导剂1,5-二[3,3’-5,5-二甲基乙内酰脲]]戊烷(PMDH), 对合成方法和路线进行了优化,并通过元素分析、质谱、核磁和红外进行了表征. 利用单晶X射线衍射仪测定了化合物的晶体结构,晶体属于三斜晶系,空间群为P1, 晶体学参数为: a =0.874 1(4) nm, b =1.114 6(2) nm, c =1.721 0(3) nm, α= 87.20(3)°,β= 89.77(3) °, γ=85.12(3)°, V= 1.668 6(6) nm3 ,Z=4.最终偏离因子R1= 0.0651.分子中的碳链连接两个乙内酰脲五元环,五元环与和它相连的两个羰基氧原子呈平面结构, 分子间存在较强的氢键.  相似文献   

17.
Alangium, the sole genus in the family Alangiaceae, has a variety of about 20 species distributed in the tropical and subtropical area of the Eastern Hemisphere, and 13 species are known to occur in the south of China1. A. plantanifolium and A. chinense are used in chinese traditional medicine for the treatment of rheumatalgia, paralysis, cardianeuria, and wound2. Pharmacological studies of the extracts of these two species showed muscular relaxing activity, and anabasine was considered as t…  相似文献   

18.
合成顺式 -二 (乙二胺 )二硝基合钴 (Ⅲ )酒石酸盐cis [Co(en) 2 (NO2 ) 2 ]·1/2C4 H4 O6超分子化合物 ,(C6H18N6O7Co ,Mr=345 .2 ) ,用X射线衍射方法确定了晶体结构。晶体学参数 :单斜晶系 ,空间群P2 1/a ,a =13.90 1(3) ,b =6 .5 2 5 (5 ) ,c=14 483(4 ) ,β =10 1.13(2 )°,V =12 89.1(4 ) 3,Z =4,Dc=1.779g/cm3,μ(CuKα) =10 6 .6 9cm- 1,F(0 0 0 ) =72 0。结构由重原法、直接法和Fourier合成法解出 ,最终偏离因子R =0 .117,Rw=0 .0 74。Co(Ⅲ )与 6个N原子形成变形八面体构型 ,酒石酸阴离子处在 4个Co(Ⅲ )正离子所包围的空穴中。  相似文献   

19.
Commercially available linear alkylbenzenesulfonates (LASs) are a mixture of various homologues and isomers, leading to 20 major species. In this work we investigated the commercial product by liquid chromatography-solid phase extraction-nuclear magnetic resonance spectroscopy-mass spectrometry (LC-SPE-NMR/MS). The commercial product was separated into 17 fractions by liquid chromatography (LC). After chromatographic separation, 5% of the flow was split to a mass spectrometer (MS) while 95% was send to post-column solid phase extraction cartridges for enrichment of the analytes (LC-SPE). After elution from the SPE-cartridges a NMR-spectrometer equipped with a cryo-probe was used for the characterisation of the different LASs species. For the first time 1H-1D and H-H-COSY spectra for 14 LASs species out of 20 major isomers are presented, whereas the 6 remaining species are detected as mixtures in 3 1H-1D and H-H-COSY spectra. These data were used to correlate the chromatographic retention of the LASs isomers to the substitution pattern of the alkyl chain.  相似文献   

20.
李迎  林钊  李蓉卓  刘霞 《化学学报》2012,70(11):75-79
基于双通道表面等离子体子共振(surface plasmon resonance,SPR)传感器,分别采用直接法和金纳米粒子作为传感层的方法,通过检测赭曲霉毒素A(ochratoxin A,OTA)合成初期阶段表达的聚酮合成酶(polyketide synthase,PKS)基因的25个特异性碱基的寡核苷酸链,建立了一种高灵敏、间接检测OTA的新方法.同时考察了6-巯基己醇(6-mercapto-1-hexanol,MCH)作为封闭液对SPR响应信号的影响.结果表明,直接法的检测限为12.5 nmol/L,MCH的加入可使响应信号有所增强,使用金纳米粒子作为传感层的检测下限为0.25 nmol/L,与直接法相比较灵敏度提高了50倍,与以往使用金纳米粒子标记抗体或抗原相比,其作为传感层也能大大提高SPR检测灵敏度,且操作简单易行.  相似文献   

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