Catalytic hydrolysis of phosphate diester (BNPP) and plasmid DNA by mononuclear macrocyclic polyamine metal complexes

The activities of the catalytic hydrolysis of phosphate diester （BNPP） [bis（p-nitrophenyl）phosphate diester] and plasmid DNA （pUC 18） by mononuclear macrocyclic polyamine metal complexes have been investigated in this paper. The results showed that the highest activity in hydrolysis of BNPP was obtained with le--Zn（II） complex （composed of lipophilic group） as catalyst. The hydrolysis rate enhancement is up to 3.64 × 10^4 fold. These metal complexes could effectively promote the cleavage of plasmid DNA （pUC18） at physiological conditions.

Preparation and Characterization of Hydroxyiron-Montmorillonite Complexes

Hydroxy Fe ions react slowly with montmorillonite by intercalation into their interlayer space and adsorption on their surface to form various hydroxyiron montmorillonite complexes. Hydroxyiron montmorillonite complexes are assumed to have the ability to adsorb anions such as H 2PO - 4, HPO 2- 4, CrO 2- 4, CrO - 2, H 2AsO - 4, HAsO 2- 4 , AsO 3- 4 and F -, which may come from weathered rocks or waste industrial water, and result in concentration of P, Cr, As and F in soil. In this paper, hydroxy Fe ions including Fe(OH) 2+ , Fe(OH) + 2 and Fe 2(OH) 2+ 2 are prepared through hydrolysis of iron in acid solutions with different pH values. Corresponding hydroxyiron montmorillonite complexes are obtained by intercalation and adsorption of these hydroxy Fe ions into the interlayer space and on the surface of montmorillonite. The obtained hydroxyiron montmorillonite complexes are characterized with XRD and DTA, showing that they have similar basal space and thermal stability with Fe montmorillonite.

Intercalation Assembly, Characterization and Luminescent Properties of Novel Supramolecular Composite Materials, Tb(Ⅲ) Complex with Tetrapodal Ligand-Montmorillonite

Two kinds of Tb（ Ⅲ ） complexes with tetrapodal ligand, [TbL（NO3）]^3＋ and [TbL]^3＋ （L： 1,1, 1＇, 1＇-tera （ 2-pyridinecarboxylester ）-di （ trimethylpropane）） were intercalated into the interlayer space of montmorillonite （MT） by ion exchange and coordination reaction of L with the Tb^3＋ ion existing in the interlayer space of Tb-MT respectively. The obtained luminescent supramolecular composite materials, [ TbL （NO3） ]^2＋-MT and [TbL]^3＋-MT were characterized by elemental analysis, XRD, FT-IR, UV-vis and thermal analysis. At the same time, the luminescent properties of the materials were also studied. The results show that the intercalated materials with regular layered structure, good thermal stability and the interlayer spacing （d001） approximates to the size of the complex ions which are located in the interlayer space of MT in the form of a monolayer.

Synthesis of novel 1:2 Fe-complexed dye containing polyamine groups

A Fe-complexed dye containing crosslinkable polyamine groups was synthesized through diazotization and coupling reaction, chlorination, amination and metallization. The structure of the Fe-complexed crosslinking dye was characterized by FT-IR and Atomic Absorption Spectroscopic techniques. The dyeing and light fastness properties of the Fe-complex on silk and wool were tested, and the results showed that the novel Fe-complex exhibited both high fixation and good light fastness.

Interaction between Bifunctional Dioxo Macrocyclic Polyamine Co(II) Complex and DNA in Metallomicellar System

The cleavage of DNA (pUC18) by lipophilic macrocyclic polyamine Co(II) complex was investigated in metallomicellar system. The results showed that the conversion of plasmid DNA (pUC18) increases with the increase of the concentration of complex under physiological conditions.

Role of the Interlayer Space of Montmorillonite in Hydrocarbon Generation: A Combined Study by TG-FTIR and High Temperature-Pressure Pyrolysis

The interlayer clay-organic complex is an important clay-organic association in sedimentary environments. The interlayer region of clay minerals not only provides storage space for organic matter, but also possesses solid acid sites; and these acid sites were proposed to be involved with the transformation of organic matter into liquid and gaseous hydrocarbons. However, the effect of the organic matter storage in the interlayer space of clay minerals on the hydrocarbons generation has not been made clear. In this study, the interlayer complex of 12-aminolauric acid (ALA) and Na+-montmorillonite (Na+-Mt), labeled as ALAinter-Mt (Na), was synthesized to investigate the role of the interlayer space of montmorillonite in hydrocarbon generation. Simply mixed ALA-Mt complex [ALA-Mt (Na)] was also prepared for comparison. The pyrolysis of ALA and ALA-Mt complexes was studied using thermogravimetry coupled with Fourier transform infrared spectroscopy (TG-FTIR) and a high temperature-pressure system (a confined gold capsule-autoclave system).

Potent trophic activity of spermidine supramolecular complexes in in vitro models

AIM:To test the growth-promoting activity of the polyamine spermidine bound to various polymeric compounds in supramolecular complexes.METHODS:A thiazolyl blue cell viability assay was used to determine the growth-promoting potency of spermidine-supramolecular complexes in a human skin fibroblast cell line exposed to spermidine and different spermidine-supramolecular complexes that were obtained by combining spermidine and polyanionic polymers or cyclodextrin.Reconstituted human vaginal epithelium was exposed to a specific spermidinesupramolecular complex,i.e.,spermidine-hyaluronan(HA)50,and cell proliferation was determined by Ki-67immunohistochemical detection.Transepithelial electrical resistance and histological analysis were also performed on reconstituted human vaginal epithelium to assess tissue integrity.RESULTS:The effect of spermidine and spermidinesupramolecular complexes was first tested in skin fi-broblasts.Spermidine displayed a reverse dose-related mode of activity with mmol/L growth inhibition,whereas 30%stimulation over basal levels was detected at mol/L and nmol/L levels.Novel spermidine-supramolecular complexes that formed between spermidine and polyanionic polymers,such as HA,alginate,and polymaleate,were then tested at variable spermidine concentrations and a fixed polymer level(0.1%w/v).Spermidine-supramolecular complexes stimulated the cell growth rate throughout the entire concentration range with maximal potency(up to 80%)at sub-mol/L levels.Similar results were obtained with spermidine-(-cyclodextrin),another type of spermidine-supramolecular complex.Moreover,the increased expression of Ki-67 in the reconstituted human vaginal epithelium exposed to spermidine-HA 50 showed that the mode of action behind the spermidine-supramolecular complexes was increased cell proliferation.Functional and morphological assessments of reconstituted human vaginal epithelium integrity did not show significant alterations after exposure to spermidine-HA,thus supporting its safety.CONCLUSION:Spermidine found in spermidine-supramolecular complexes displayed potentiated regenerative effects.Safety data on reconstituted human vaginal epithelium suggested that assessing spermidinesupramolecular complex efficacy in atrophic disorders is justified.

Adsorption of As on hydroxy-Fe-montmorillonite complexes

Arsenate has high affinity for soluble hydroxy-Fe species and Fe-oxyhydroxide pre-cipitates. In addition, the hydrolysis of Fe(III) and the growth of the initially precipitated Fe(III) phases are strongly influenced by the presence of montmorillonite. In this paper, the adsorption of As onto various hydroxy-Fe-montmorillonite (H-F-M) complexes was studied. Three systems of samples were prepared by mixing montmorillonite, hydroxy-Fe and arsenate in different se-quences: (1) Prior mixing of montmorillonite and hydroxy-Fe before the addition of arsenate; (2) prior mixing of hydroxy-Fe and arsenate before the addition of montmorillonite; and (3) prior mixing of montmorillonite and arsenate before the addition of hydroxy-Fe. For each system, the effects of pH, ionic strength, temperature, initial Fe and As concentrations and adsorption dura-tion on the overall uptake of As by H-F-M complexes were studied. Results showed that the up-take of As increased with increasing pH, temperature, initial Fe concentration and adsorption duration, and decreased with increasing ionic strength and initial As concentration to different extents for the three systems. The variation of the As uptake of H-F-M complexes with pH in the range of study is opposite to that reported previously for Fe-O-H systems in the absence of montmorillonite and similar to that reported for montmorillonite in the absence of hydroxy-Fe. The marked influence of ionic strength on the As uptake of H-F-M complexes indicates that outer-sphere complexation plays an important role. This is quite different from the adsorption of As on the surface of either Fe-oxyhydroxides or montmorillonite alone in which inner-sphere complexation dominates. Under all experimental conditions, the H-F-M complexes studied dis-played a very strong affinity for As, among which system 2 had the highest As adsorption capac-ity and system 1 the lowest. The authors attribute this to the differences in mixing sequence which resulted in more hydroxy-Fe (the main adsorbent for As) in system 1 adsorbing onto montmorillonite before adsorbing As than in systems 2 or 3.

Synthesis, Structure and Antitumor Activities of [Ni(dien)_2] [Ni(CN)_4] Complex

Ni(II)-dien complex was prepared and characterized by X-ray diffraction. The crystal belongs to triclinic system, space group P-1, with crystallographic parametersa=0.888 13(18) nm,b=0.890 10(18) nm,c=1. 591 8(3) nm, α=77.71(3)°, β=89.12(3)°, γ=61.24(3)°,Z=2. The two dien molecules coordinate to the central Ni atom, the six nitrogen atoms form a distorted octahedron. Preliminary pharmacological tests showed this complex had antitumor activity against HepG2 and HL-60 cell linesin vitro. Key words polyamines - Ni(II) complex - crystal structure - antitumor activity CLC number O 626 Foundation item, Supported by the National Natural Science Foundation of China (29972034)Biography: Li Tao (1976-), male, Ph. D candidate, research direction: ophthalmology and chemicalbiology.

Accelerated Hydrolysis of p-Nitrophenyl Picolinate Catalyzed by Metallomicelle Made from a Novel Macrocyclic Polyamine Copper（Ⅱ） Complex

A copper（Ⅱ） complex 1 of a novel macrocyclic polyamine ligand with hydroxylethyl pendant groups, 4,11-bis（hydroxylethyl）-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane （L） has been synthesized and characterized. Rate enhancement for hydrolysis of p-nitrophenyl picolinate （PNPP） catalyzed by 1 was studied kinetically under Brij35 micellar condition. For comparision, the catalytic activity of corresponding copper（Ⅱ） complex 2 of non-substituted macrocyclic polyamine ligand, 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraaza-cyclotetradecane （L＇） toward the hydrolysis of PNPP was also investigated. The results indicate that the macrocyclic polyamine copper（Ⅱ） complex 1 effectively catalyzed the hydrolysis of PNPP, and the pendant ligand hydroxyl group or deprotonated pendant ligand hydroxyl group can act as catalytically active species in the reaction. A ternary Complex kinetic model involving metal ion, ligand and substrate has been proposed, and the results confirmed the reasonability of such kinetic model.

大环多胺及其金属配合物的研究新进展

论述了大环多胺及其金属配合物的合成应用研究进展 ,阐述了单核 ,双核及多核大环多胺的类型及其与金属的配合情况 ,全面地论述了该类化合物的超分子识别及其对核酸的切割作用 ,并讨论了其在金属配合物的荧光及其发光性能 .

大环多胺的超分子识别作用

就大环多胺及配合物为主体分子对金属离子,磷酸根,氨基酸,肽及核苷酸等的超分子识别作用、影响因素和识别机制进行了简述.

含吡啶环大环多胺的合成及其与Cu(Ⅱ)的络合行为

大环多胺化合物是一类具有独特性质的配体,它既可以与金属离子络合,也可与带正电荷的有机铵离子或带负电荷的有机阴离子发生络合作用,以主——客体络合形式形成超分子。因此对大环多胺的合成和络合性质的研究是目前在生物有机化学(酶模型、分子催化等)、生物无机化学和配位化学等学科领域里的重要研究方向。

Cu^(2+)和Cd^(2+)在蒙脱石-胡敏酸复合体上的吸附及其竞争

土壤和水体中的腐殖酸常常与粘土矿物紧密结合成为特殊的复合体。这种粘土矿物-腐殖酸复合体对重金属的吸附作用既有别于粘土矿物,更有别于腐殖酸。以蒙脱石和胡敏酸分别作为粘土矿物和腐殖酸的代表,通过一系列实验研究了Cu2+、Cd2+在单一体系和共存体系条件下在蒙脱石-胡敏酸复合体上的吸附作用,同时探讨了二者的竞争特点。实验结果表明,在单一体系条件下,蒙脱石-胡敏酸复合体对Cu2+的吸附量始终明显大于Cd2+,且二者的吸附量均随其初始浓度的增大而呈线性增大;而在Cu2+和Cd2+共存体系条件下,Cu2+的吸附量始终略大于Cd2+的吸附量,即复合体对Cu2+的吸附有较好的选择性。在吸附过程中,复合体中的蒙脱石与Cd2+和Cu2+的阳离子交换作用处于主导地位。无论是在单一体系还是在共存体系中,Cd2+优先替换电价相同而半径略大的Ca2+,而Cu2+则优先替换半径相近、电价低的Na+。因此,Cd2+的存在使Cu2+在复合体上的吸附量明显地减小,而Cu2+的存在对Cd2+的吸附几乎没有影响。这些实验结果将有助于深入探讨重金属离子在土壤、水体等环境中的迁移-固定行为。

花状β-氢氧化镍的合成和表征

本文介绍了以大环多胺(六甲基-1,4,8,11-四氮环14-4,11-二烯)的镍"配合物溶液为反应物,水热水解制备出花状β-Ni(OH)2亚微米结构,该花状β-Ni(OH)2由几十个相互连接的纳米片构成。对中间产物的研究结果表明,随着配合物浓度的增加、反应时间的延长,产物形貌从卷曲的片状转变成纳米片组成的花状且花状结构逐渐增密。采用粉末X-射线衍射(XRD)、透射电子显微镜(TEM)和场发射扫描电子显微镜(FESEM)表征了产物,并采用Rietveld精修方法拟合了晶体结构。

低聚合羟基铁蒙脱石复合体吸附铬酸根的实验研究

在模拟的酸性土壤条件下,利用制备的低聚合羟基铁 蒙脱石复合体对铬酸根进行吸附实验。重点研究了吸附条件对复合体铬吸附能力的影响,对比了蒙脱石和含水氧化铁。结果表明,实验条件下复合体有较强的铬吸附能力,其铬吸附量低于铁沉积物而明显高于蒙脱石。铬初始质量浓度是影响复合体铬吸附量的最主要因素,离子强度次之。吸附时间(12h以上)、温度、pH值对复合体铬吸附量的影响很小;说明在酸性土壤条件下,复合体有强且稳定的铬吸附能力。

单方酰化大环四胺金属配合物与DAN相互作用研究

以1,4,7,10-四氮杂环十二烷(Cyclen)为原料,合成了单方酰化大环四胺,其结构经1HNMR,MS,元素分析等表征.通过紫外分光光谱法研究了目标化合物及其Cu(Ⅱ),Ni(Ⅱ)等金属配合物与小牛胸腺DNA(CTDNA)的相互作用.结果表明:单方酰化大环四胺和碱性溶液对DNA有增色效应,其Cu(Ⅱ),Ni(Ⅱ)金属配合物对DNA有减色效应.

多胺钴氧合配合物的室温固相合成、表征及性质

用室温固相法分别合成了以二乙三胺、三乙四胺为配体、以钴为中心离子的配合物。室温下,每摩尔配合物消耗2molO2,其中1molO2用来和钴离子配位形成超氧配合物,另外消耗的1molO2则是由于配体被活化氧氧化所致。采用混合溶济法分离出两种固态氧合配合物犤Co(NH2CH2CH2N=CHCH2NH2)2O2犦(Ac)2·2H2O和犤Co(NH2CH2CH2N=CHCH2NHCH2CH2NH2)2O2犦(Ac)2·2H2O。通过元素分析、红外光谱、电导、XRD、NMR、热分析等测试手段研究了该配合物的性质,确定了该配合物的组成,初步探讨了相关机理。

大环多胺及其金属配合物与DNA的相互作用

本文综述了近年来基于大环多胺及其金属配合物与DNA相互作用的研究进展,着重介绍本课题组在有关单双核、多核以及功能化大环多胺衍生物及其金属配合物与DNA相互作用方面的研究和发现,并对其在化学核酸酶方面的应用进行了讨论。在单双核大环多胺衍生物方面,我们分别合成了以吡啶、苯环、咪唑、三氮唑为侧臂的单核大环多胺金属配合物,同时合成了以刚性桥相连的双核配合物和以柔性链相连的双核配合物。研究这些单双核大环多胺与DNA的相互作用发现,以刚性链相连的双核大环多胺金属配合物具有很好的切割DNA的性质,可以在低浓度、短时间内切断DNA。在功能化大环多胺方面,我们合成了含有碱基P、NA单体、咪唑盐、冠醚、二茂铁等功能化基团的大环多胺衍生物及金属配合物,并研究了其与DNA的相互作用。在多核大环多胺方面,我们合成了基于大环多胺的寡聚物,研究发现该类物质可与DNA形成复合物,从而有效地保护DNA免于酶解。

季铵盐复配硅烷偶联剂改性蒙脱土的制备及表征

制备十八烷基三甲基氯化铵(OTAC)复配γ-氨丙基三乙氧基硅烷(KH550)改性蒙脱土(MMT),利用XRD、ICP、FTIR、TG和SEM对改性前后的蒙脱土进行表征。结果表明MMT层间距的扩大主要是由于OTAC与MMT层间阳离子交换的结果,质子化的KH550亦能与MMT进行离子交换但不影响OTAC对MMT的有机改性,而且KH550能与MMT表面羟基反应形成化学键而接枝于MMT表面。