神经递质多巴胺在AQ修饰组合微电极上的伏安行为及其伏安溶出法测定

本研究了神经递质多巴胺（ＤＡ）在ＡＱ聚合物薄膜修饰组合微盘电极上的电化学行为。结果表明，在ｐＨ７．０的磷酸缓冲溶液中，修饰组合微盘电极经电化学处理后，ＤＡ的氧化还原峰电位差较小（约为８０ｍＶ），氧化峰、还原峰的峰形比较对称。在选定条件下，ＤＡ的伏安溶出峰电流与浓度在１．０×１０＾－６～８．０×１０＾－４ｍｏｌ／Ｌ范围内呈线性关系。厚的ＡＱ膜修饰组合微电极可基本上消除抗坏血酸的干扰。利用ＡＱ膜修饰     

聚苯胺修饰电极上抗坏血酸与多巴安胺氧化峰的分离

本文介绍了一种分离抗坏血酸（ＡＡ）和多巴胺（ＤＡ）氧化峰的新方法。聚苯胺（ＰＡ）ＡＡ和ＤＡ有不同的催化性。因而在ＰＡ修饰电极上，ＡＡ和ＤＡ在不同的电位被氧化，从而解决了二者氧化峰不能分离的问题。实验表明，在ＰＡ膜电极上，ＡＡ和ＤＡ氧化峰可分开约１４０ｍＶ。     

聚2-吡啶甲酸修饰电极伏安法测定多巴胺

用循环伏安法制备了聚２－吡啶甲酸修饰玻碳电极，研究了神经递质多巴胺（ＤＡ）在该聚合物薄膜修饰电极上的电化学行为。实验结果表明，在ｐＨ７．０的磷酸盐缓冲溶液中，ＤＡ在该电极上的线性范围为１．０×１０－７～１．０×１０－５ｍｏｌ／Ｌ。该修饰电极对抗坏血酸（ＡＡ）无响应，从而可有效消除其对ＤＡ测定的干扰。     

2-氨基吡啶修饰电极的电化学性质及对抗坏血酸的测定

研究了２－氨基吡啶聚合膜修饰玻碳电极的制备及其电化学性质,并用于抗坏血酸（ＡＡ）的测定。在ｐＨ５．７ＢＲ缓冲溶液中,ＡＡ在 ２－氨基吡啶修饰电极上产生一灵敏的氧化峰,峰电流与ＡＡ浓度在４ × １０－６～１０－３ｍｏｌ／Ｌ范围内呈良好的线性关系,检测下限为 １．３ × １０－６ｍｏｌ／Ｌ。该电极对 ＡＡ有增敏作用,对多巴胺（ＤＡ）有排斥作用,重现性良好,可用于ＡＡ的测定。     

铁氰化镍化学修饰电报对多巴胺电催化氧化及其测定

本文采用电化学方法在导电基体电极上制备出性能追定的铁氰化锌（ＮｉＨＣＦ）修饰膜电极，对Ｎｉ－ＨＣＦ膜电极的电化学行为进行了表征，并研究了其对神经传导物质，多巴胺（ＤＡ）的电催化氧化作用。结果表明对于在空白玻碳电报（ＧＣ）上氧化电位较高的ＤＡ，ＮｉＨＣＦ在可通过媒介作用促其氧化电位降低约２００ｍＶ，大大提高了其电子转移速率；而且在ＤＡ的浓度为１．０×１０－６—１．０×１０－２ｍｏｌ／Ｌ范围内，催化峰电流与ＤＡ浓度呈良好的线性关系，检测限可达５．０×１０－７ｍｏｌ／Ｌ。用于ＤＡ药物针剂的测定，结果良好。     

化学合成环取代聚苯胺的电化学行为

聚邻甲苯胺，聚２，５－二甲氧苯胺和聚间氯化苯胺由化学法合成而得，用它们的二甲基甲酰胺溶液在铂上成膜以制得聚合物修饰电极，循环伏安实验表明：在１ｍｏｌ／Ｌ Ｈ２ＳＯ４中，ＰＯＴ的氧化还原分两步进行，呈现两对氧化还原峰，ＰＤＭＡｎ只在较负的电位区呈现两对氧化还原峰，而ＰＣｌＡｎ不呈氧化还原活性。     

杂多酸—聚（二烯丙基二甲基氯化铵）多层膜在4—氨基硫酚修饰金电极上的组装

通过电化学生长法在４－氨基硫酚自组装膜修饰金电极上制备了包含杂多酸（ＳｉＭｏ１１ＶＯ＾５－４０和聚合物阳极离子ＰＤＤＡ的多层膜修饰电极。用循环伏安法研究了该多层膜的电化学行为,结果表明,Ｍｏ的第３个还原峰随多层膜层数的增加显著增长,而另两个还原峰增长缓慢。该修饰电极的峰电位随ＰＨ的增加而线性负移,表明有氢离子参与杂多酸的氧化还原反应。该修饰电极对ＢｒＯ＾－３和ＮＨＯ２的还原反应有良好的催化作用,催化电流随着层数的增加而增长,并且Ｍｏ的第三个还原峰电流与ＣＲｒＯ＾－３有良好的线性关系。     

铂微粒修饰聚2，5－二甲氧基苯胺电极对甲醇的电催化作用

将以铂微粒修饰玻碳电极（ＧＣ）为基体的聚２，５－二甲氧基苯胺膜（ＰＤＭＡ）形成修饰电极（Ｐｔ／ＰＤＭＡ／ＧＣ）．循环伏安实验表明，Ｐｔ／ＰＤＭＡ／ＧＣ电极对甲醇氧化比分散于玻碳电极上的铂催化活性更大。讨论了ＰＤＭＡ膜厚度、铂微粒含量及甲醇浓度对催化活性的影响。这种电极在酸性甲醇溶液中具有良好的稳定性。     

铂微粒修饰聚2,3—二甲氧基苯胺电极对甲醇的电催化作用

将以铂微粒修饰玻碳电极为基体的聚２，５－二甲氧基苯胺膜形成修饰电极循环伏安实验表明，Ｐｔ／ＰＤＭＡ／ＧＣ电极对甲醇氧化比分散于破碳电极上的铂催化活性更大，讨论了ＰＤＭＡ膜厚度，铂微粒含量及甲醇浓度对催化活性的影响，这种电极在酸性甲醇溶液中有良好的稳定性。     

辅酶Ⅰ在苯并咪唑修饰银电极上的还原反应

辅酶Ⅰ在苯并咪唑修饰银电极上的还原反应李根喜，陈洪渊，朱德煦（南京大学生物化学系，生物医药技术国家重点实验室，化学系，南京，２１００９３）关键词ＮＡＤ~＋，苯并咪唑，化学修饰电极还原态烟酰胺辅酶Ⅰ（ＮＡＤＨ）的氧化反应已进行了大量研究。但有关氧化态辅?..     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.