用于潜在MRI造影剂的DTPA酰胺配合物的制备及性能

通过酰化反应将与水合肼缩合的靛红希夫碱引入到二乙烯三胺五乙酸(DTPA)中得到新型配体,再与GdⅢ、MnⅡ、FeⅢ配位得到3种顺磁性金属配合物。采用傅里叶变换红外光谱(FTIR)、核磁共振氢谱(1HNMR)、热重及差热分析(TG-DTA)、电感耦合等离子体发射光谱和元素分析进行了表征。采用反转恢复法研究了配合物分别在水中和牛血清蛋白(BSA)中的纵向弛豫率,结果表明,GdⅢ、MnⅡ配合物的纵向弛豫效率r1分别为9.2L/(mmol·s)和8.9 L/(mmol·s),均高于商用造影剂Gd-DTPA的弛豫率〔3.5 L/(mmol·s)〕。     

以低窄壳糖为载体的磁共振/荧光双功能成像分子探针的合成及性质研究

通过微波辅助氧化法降解壳聚糖制得低聚窄分子量分布壳聚糖(低窄壳糖),LNCS6(聚合度为6,Mw/Mn=1.08),并以LNCS6为载体,键接7-羟基-8-醛基香豆素(CA)为荧光基团、二乙烯三胺五乙酸(DTPA)为络合基团,络合三价钆离子最终制得一种潜在的核磁共振(MR)/荧光双功能成像分子探针Gd[DTPA/CA-LNCS6]。研究了其磁共振成像效果以及荧光特性,并通过等温微量热滴定法(ITC)测定了产物与牛血清蛋白(BSA)之间的结合常数及热力学参数。结果表明,所得产物具有较高的体外磁共振成像效果〔r1=13.71 L/(mmol·s)〕,远高于目前临床使用的马根维显〔r1=3.63 L/(mmol·s)〕。同时,其具有显著的荧光特性(λmax=438 nm),与牛血清蛋白之间结合常数Ka104,适用于血液输送,对这类探针精细化工中间体的合成具有较好的参考与借鉴作用。     

以低窄壳糖为载体的MR/荧光双功能成像分子 探针的合成及性质研究

摘 要：通过微波辅助氧化法降解壳聚糖制得低聚窄分子量分布壳聚糖（低窄壳糖）,LNCS6（聚合度为6,Mw/Mn = 1.08）,并以LNCS6为载体,键接7-羟基-8-醛基香豆素（CA）为荧光基团、二乙烯三胺五乙酸（DTPA）为络合基团,络合三价钆离子最终制得一种潜在的核磁共振（MR）/ 荧光双功能成像分子探针Gd[DTPA/CA-LNCS6]。 研究了其磁共振成像效果以及荧光特性,并通过等温微量热滴定法（ITC）测定了产物与牛血清蛋白（BSA）之间的结合常数及热力学参数。实验结果表明,所得产物具有较高的体外磁共振成像效果〔（r1=13.71 L/(mmol • s)〕,远高于目前临床使用的马根维显〔r1=3.63 L/(mmol • s)〕。同时具有显著的荧光特性（λmax=438nm）,与牛血清蛋白之间结合常数Ka>104,适用于血液输送,对这类探针精细化工产品的合成具有较好的参考与借鉴作用。     

浅议含芳寡聚稀土配合物的合成与表征

磁共振成像(Magnetic Resonance Imaging,MRI)造影剂是用来增强正常与病变组织之间的磁共振信号对比度的一类顺磁性化学试剂,而顺磁性金属离子的配合物因有较大的磁距,能通过偶极相互作用缩短临近核的弛豫时间,这种顺磁性的化合物进入人体内后,能选择性地集中在某些组织中,且可以缩短局部组织质子的弛豫时间,增强信号强度及对比度,从而能探测出微小的病变部位。为研究这种含顺磁性物质的磁共振成像造影剂,本论文选用Gd3+、Mn2+和Fe3+分别与含芳酰胺寡聚配体H2L1和H3L2,进行络合反应,得到6种新型的含芳酰胺寡聚顺磁性金属配合物。再通过元素分析、红外、化学滴定、热重-差热分析等方法对配合物进行组成与结构表征。     

磁性N-羧甲基壳聚糖造影剂的制备及性能

采用简单经济(与传统微乳法、热分解法等比较)的方法制备出一种磁性N-羧甲基壳聚糖造影剂。首先对壳聚糖的氨基进行羧甲基化制备N-羧甲基壳聚糖,然后在其链上采用原位生成Fe3O4纳米粒子的方法制备出磁性N-羧甲基壳聚糖,并对其进行了表征及性能的测试。热重分析结果表明,Fe3O4的生成量与N-羧甲基壳聚糖中羧甲基的含量有关,其生成量随着羧甲基含量的增加而增加,但当羧甲基的含量增加到一定程度时,Fe3O4的生成量达到某一峰值。透射电镜结果表明,生成的Fe3O4纳米粒子的粒径约为5～10 nm。磁共振成像结果显示,该磁性N-羧甲基壳聚糖的横向弛豫率为82.82 mmol/(L.s),高于超顺磁性氧化铁作为磁共振成像造影剂时R2需大于62 mmol/(L.s)的最低标准,可作为潜在的磁共振成像阴性造影剂。     

吡唑-3-甲酸钴的合成、晶体结构及其与牛血清白蛋白的相互作用

利用吡唑-3-甲酸为配体,通过溶液法与氯化钴反应合成出一种钴的配合物,用X射线单晶衍射仪对其进行表征。结果显示,该配合物为单斜晶系,空间群为P21/c,a=0.509 94(2)nm,b=1.139 55(5)nm,c=0.936 80(4)nm,β=95.925(5)°。钴与两个配体分子的N、O原子和水分子的氧原子配位,形成八面体结构。利用紫外-可见吸收光谱与荧光光谱研究它与牛血清白蛋白(BSA)的相互作用。结果表明,该配合物与BSA形成稳定的复合物,荧光猝灭属于静态猝灭,猝灭速率常数kq为3.54×1012L/(mol·s),结合常数K=7.06×105L/mol,结合位点n=1.259 5。     

潜在的T2类造影剂Fe3O4@BSA纳米粒子的合成及性能研究

制备了Fe_3O_4@BSA磁性纳米功能材料,包裹在Fe_3O_4纳米粒子表面的牛血清白蛋白(BSA)主要起到分散剂和稳定剂的作用。通过傅里叶变换红外光谱、X射线衍射、透射电子显微镜及热重分析对合成的Fe_3O_4@BSA纳米粒子进行了表征和分析。结果表明,制备的Fe_3O_4@BSA纳米粒子中BSA质量分数约为18.9%。体外成像结果表明,随着Fe_3O_4@BSA纳米粒子浓度的增加,T2成像信号增强,具有明显的阴性造影效果。于0.5 T外磁场下,测得Fe_3O_4@BSA纳米粒子的横向弛豫率(transverse relaxivity,r2)为148.18 L/(mmol·s)。结果表明,Fe_3O_4@BSA纳米粒子能够作为一种潜在的T2类磁共振成像造影剂。     

槲皮素钕配合物与牛血清白蛋白相互作用的荧光光谱研究

在p H为7.40的Tris缓冲体系下,利用荧光光谱法及紫外-可见吸收光谱法研究了槲皮素钕配合物与牛血清白蛋白(BSA)相互作用。研究表明:槲皮素钕配合物对BSA有较强的荧光猝灭作用,其猝灭方式为静态猝灭。依据Stern-Volmer方程得出25℃,29℃,33℃,37℃下槲皮素钕配合物与BSA的结合常数分别为1.520×106 L·mol-1、8.293×105 L·mol-1、6.833×105 L·mol-1、6.314×105 L·mol-1,发现随温度上升结合常数k值下降,二者之间的结合位点数为1;根据F?rster非辐射能量转移理论求得槲皮素钕配合物与BSA作用的结合距离为2.56 nm。     

La3+和Dy3+壳聚糖配合物与牛血清白蛋白相互作用

在模拟人体生理条件下,利用荧光、紫外-可见吸收和同步荧光光谱法研究了水溶性壳聚糖(CS)及两种壳聚糖稀土配合物(CS-La和CS-Dy)与牛血清白蛋白(BSA)的相互作用. 紫外吸收光谱分析表明,CS, CS-La和CS-Dy相互作用的最大吸收峰强度都增加. 用Stern-Volmer方程分别对荧光光谱的实验数据进行分析,发现CS-La对BSA的荧光猝灭作用属于静态荧光猝灭,反应生成新的复合物. 而CS和CS-Dy对BSA的荧光猝灭作用有静态荧光猝灭和动态猝灭,发生了分子内的非辐射能量转移. 求得三种物质在室温和体温的情况下与BSA相互作用过程的结合常数KA [291 K, CS-BSA: 1.807′104 L/(g·s), CS-La-BSA: 3.065′104 L/(g·s), CS-Dy-BSA: 2.193′104 L/(g·s); 310 K, CS-BSA: 2.665′104 L/(g·s), CS-La-BSA: 2.022′104 L/(g·s), CS-Dy-BSA: 7.246′104 L/(g·s)]和相关热力学参数;确定了CS和CS-Dy与BSA之间的主要作用力是静电和疏水作用力,而CS-La与BSA之间的作用力主要为范德华力和氢键等作用力. 同步荧光光谱表明,CS, CS-La和CS-Dy均对牛血清白蛋白的构象和所处的微环境产生影响.     

6-甲基-4-(4-甲氧酰基苯基)-5-甲氧羰基-3,4-二氢嘧啶-2-酮的合成及与牛血清白蛋白的相互作用

合成并表征了6-甲基-4-(4-甲氧酰基苯基)-5-甲氧羰基-3,4-二氢嘧啶-2-酮,利用荧光光谱法和紫外光谱法研究了该化合物与牛血清白蛋白(BSA)的相互作用。结果表明,化合物对BSA内源荧光的猝灭为静态猝灭;化合物与BSA的结合常数(Ka)和结合位点数(n)在298 K时分别是7.043 7×102L/mol和0.970 3,化合物与BSA以接近1∶1(物质的量比)的比例生成基态复合物;热力学数据表明化合物与BSA主要以疏水作用力相结合(ΔH0,ΔS0,ΔG0);结合距离(r)为3.49 nm,表明化合物与BSA分子之间发生了非辐射能量转移。     

新型三脚架结构席夫碱及其过渡金属配合物的合成与性质

三{2-[(2-甲酰基苯基)氧代]乙基}胺与乙醇胺缩合得到一种新型席夫碱配体,然后与Cd、Mn、Co、Ni、Fe、Cu过渡金属配位得到其配合物,经元素分析、红外光谱、紫外光谱、核磁共振谱表征,确定了配体及配合物的组成,并对配体及配合物杀菌活性进行了研究.     

A Model Compound Study: The Formation of Colored Metallic Extractive Complexes and Their Effect on the Brightness of Tmp Pulp

Abstract

Flavonoids, such as Quercetin, are the main polyphenol compounds found in extractives. When complexing with transition metal ions, these extractives may induce a significant discoloration to mechanical pulps. In this study, the effect of metallic extractive complexes was investigated using a model compound, Quercetin. It was confirmed that the complexes formed between some metal ions and Quercetin are strongly colored. However, most of the strong absorbance in visible light due to metallic Quercetin complexes, can be eliminated by the addition of diethylenetriaminepentaacetic acid (DTPA). The metal ions studied were Fe(III), Cu(II), Mn(II) and AI(III).     

Evaluation of mixed cation–anion exchange resins as extractants for potentially available micronutrients in tropical soils

We examined the possibility of using mixed cation–anion exchange resinspre-treated with two organic acid ligands, acetate (R-ACET) and tartrate(R-TART) for extraction of phytoavailable Fe, Mn, Cu and Zn using theconventional diethylenetriaminepentaacetic acid (DTPA) as a referenceextractant. In each soil, variable amounts of Fe, Mn, Cu and Zn were extractedby the different extractants. The amounts of Fe, Mn, Cu and Zn did not followprediction based on stability constants of metal-organic complexes. The R-ACETwas a slightly better predictor of soybean uptake of Cu and Mn, and dry matter(DM) yield responses to Cu than either DTPA or R-TART, though differencesbetweenR-ACET and DTPA were not significant. However, soybean DM yield response to Znwas best predicted by DTPA, while Zn uptake correlated more strongly with DTPAthan R-ACET and R-TART extractable Zn. These results suggest that R-ACET may beused as an alternative extractant for Fe, Mn, Cu and Zn in strongly weatheredtropical soils, but it was not superior to DTPA.     

氰桥化合物[cis-Fe(bpy)2(CN)2Mn(L)]2[PF6]4的合成及其对金属离子选择识别作用

将Mn(Ⅱ)离子、有机配体L(L=1,6-二苯基-2,5-双(2-甲基吡啶基)-2,5-二重氮己烷)和氰基化合物cis-FeⅡ(bpy)2(CN)2·3H2O(bpy=2,2′-联吡啶)在NH4PF6存在下制备一个四元环异核氰桥化合物即标题化合物,并对其结构进行表征。重金属离子对标题化合物的荧光响应研究表明,标题化合物对Cu(Ⅱ)和Fe(Ⅲ)有很好的选择性。随着金属离子Cu(Ⅱ)和Fe(Ⅲ)的加入,标题化合物的荧光强度逐渐降低至基本消失。随着金属离子Pb(Ⅱ)和Fe(Ⅱ)的加入,标题化合物的荧光强度逐渐降低,当金属离子加到一定浓度,标题化合物的荧光强度不随金属离子的变化而变化。对于Co(Ⅱ)、Cr(Ⅲ)、Mn(Ⅱ)、Cd(Ⅱ)、Ni(Ⅱ)、Zn(Ⅱ)等离子,随着金属离子的加入标题化合物的荧光强度改变甚微或不改变。     

Polystyrene anchored vanillin Schiff base—Complexation and ion removal studies

A set of six new polystyrene anchored metal complexes have been synthesized by the reaction of the metal salt with the polystyrene anchored Schiff base of vanillin. These complexes were characterized by elemental analyses, Fourier transform infrared spectroscopy, diffuse reflectance studies, thermal studies, and magnetic susceptibility measurements. The elemental analyses suggest a metal : ligand ratio of 1 : 2. The ligand is unidentate and coordinates through the azomethine nitrogen. The Mn(II), Fe(III), Co(II), Ni(II), and Cu(II) complexes are all paramagnetic while Zn(II) is diamagnetic. The Cu(II) complex is assigned a square planar structure, while Zn(II) is assigned a tetrahedral structure and Mn(II), Fe(III), Co(II), and Ni(II) are all assigned octahedral geometry. The thermal analyses were done on the ligand and its complexes to reveal their stability. Further, the application of the Schiff base as a chelating resin in ion removal studies was investigated. The polystyrene anchored Schiff base gave 96% efficiency in the removal of Ni(II) from a 20‐ppm solution in 15 min, without any interference from ions such as Mn(II), Co(II), Fe(III), Cu(II), Zn(II), U(VI), Na⁺, K⁺, NH₄⁺, Ca²⁺, Cl^?, Br^?, NO₃^?, NO₂^?,and CH₃CO₂^?. The major advantage is that the removal is achieved without altering the pH. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1536–1539, 2005     

Synthesis and the magnetic properties of novel metal(II) complexes of polyamides

Novel polyamides DTPA and DTPyA are prepared from 2,2′-diamino-4,4′-bisthiazole and aromatic polycarbonyl chloride. The complexes of Fe(II) and Cu(II) metal of the polyamides are also prepared. The complexes as well as the polyamides are characterized through IR and EPR, and the magnetic property of each complex are measured through MPMS. It is found the Fe(II) complexes of both DTPA and DTPyA reveal magnetization ability, especially the Fe(II) DTPA complex. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 818–822, 2001     

芦丁配合物的合成研究进展

芦丁及其衍生物具有广泛的药理活性。芦丁具有完整的大盯键共轭体系,强配位氧原子与合适的空间构型,可与金属离子螯合成稳定的环状配合物。研究表明：这些配合物有些具有明显的生物活性,有些药理作用显著。到目前为止,国内外共合成了31种芦丁金属配合物,其中主族元素有5个：Mg、Al、Ga、Sn和Bi;副族元素有12个：Cr、Mn、Fe、Co、Ni、Cu、Zn、Y、Mo、Cd、Pt和Au;稀土元素有14个：La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu等。     

Synthesis,characterization, and catalytic activity of 4 mol % N,N′‐methylene bisacrylamide crosslinked poly(acrylic acid)–metal complexes

The metal‐ion complexation behavior and catalytic activity of 4 mol % N,N′‐methylene bisacrylamide crosslinked poly(acrylic acid) were investigated. The polymeric ligand was prepared by solution polymerization. The metal‐ion complexation was studied with Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) ions. The metal uptake followed the order: Cu(II) > Cr(III) > Mn(II) > Co(II) > Fe(III) > Zn(II) > Ni(II). The polymeric ligand and the metal complexes were characterized by various spectral methods. The catalytic activity of the metal complexes were investigated toward the hydrolysis of p‐nitrophenyl acetate (NPA). The Co(II) complexes exhibited high catalytic activity. The kinetics of catalysis was first order. The hydrolysis was controlled by pH, time, amount of catalyst, and temperature. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 272–279, 2004     

The roles of H-bonding, π-stacking,and antiparallel CO ⋯ CO interactions in the formation of a new Gd(III) coordination polymer based on pyridine-2,6-dicarboxylic acid

This study reports the synthesis of a new catenane Gd(III) complex using pyridine-2,6-dicarboxylic acid (H₂pydc) as ligand. The structure of [Gd(pydc)(Hpydc)(H₂O)₂]_n (1) was characterized by IR spectroscopy, X-ray diffraction methods and the elemental analysis to check the purity of the compound. On the basis of crystallographic data, compound 1 contains a Gd(III) metal center that is coordinated to seven oxygen atoms of two tridentate and one monodentate H₂pydc ligands and two coordinated water molecules. Other lanthanoid complexes involving this ligand are available in the literature; however, this is the first example where a combination of monoanionic (Hpydc⁻) and dianionic (pydc^2 −) forms of the ligand counterbalance the Gd^3 + metal center. The intermolecular interactions in this novel system consist of different kinds of H-bonding and π-stacking interactions in addition to antiparallel CO ⋯ CO interactions which have been analyzed using DFT calculations and the Bader's theory of “atoms in molecules”.     

Spectral,XRD, SEM and biological properties of new mononuclear Schiff base transition metal complexes

Six new transition metal complexes derived from the reaction of 4(4-(dimethylamino) benzylideneamino) benzoic acid and Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) cations, were prepared, isolated and characterized by a range of spectral and analytical methods including UV/Vis, FT IR, NMR, MS, powder XRD, TGA and SEM. The complexes were formed with the deprotonation of the ligand and presented typical six-coordinated octahedral geometry. In addition, the biological activity was evaluated by conducting in vitro anti-bacterial, anti-fungal and anti-leishmanial screenings. All the complexes were found more active than the ligand, while complex 7 revealed biological significance.