耐尔兰共价键合修饰石墨电极的电化学行为及对NADH的响应研究

本文报道了耐尔兰Ａ键合型石墨修饰电极的制作方法,详细研究了修饰电极的电化学行为及对ＮＡＤＨ的响应情况。在ｐＨ７．４的磷酸盐缓冲溶液中,用该电极在０ｍＶ（ｖ．ｓＳＣＥ）电位下检测ＮＡＤＨ,响应电流与ＮＡＤＨ浓度在４．３×１０－６～５．２×１０－４ｍｏｌ·Ｌ－１范围内成线性关系,检测下限为１．２×１０－６ｍｏｌ·     

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。     

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     

辅酶Ⅰ在β－萘醌磺酸根修饰金带电极上的电化学还原

研制了聚毗咯／ＮＱＳ修饰金带电极，讨论了ＮＱＳ／ＰＰｙ的电聚合过程及实验条件对金电极上吡咯聚合物膜性质的影响；用成核及生长理论解释了阴离子ＮＱＳ对电聚合过程计时电流曲线的影响，优化了ＮＱＳ／ＰＰｙ／Ａｕ电极的制备条件．该修饰电极稳定性好，对辅酶Ⅰ在金电极上的还原有催化作用．在ｐＨ＝７．０时催化电流在４．０×１０￣（－５）～１．５×１０￣（－３）ｍｏｌ／Ｌ范围内与ＮＡＤ￣＋　浓度有线性关系，探讨了电催化作用的机制．     

葡萄糖脱氢酶微型生物传感器的研制及应用

以甲苯胺兰（ＴＢ）修饰碳糊微电极为基体，将葡萄糖脱氢酶（ＧＤＨ）用丝素蛋白膜固定于修饰微电极表面制成了生物传感器，在ｐＨ７．０的ＮａＯＨ－ＮａＨ２ＰＯ４缓冲溶液中，烟酰胺腺嘌呤二核苷酸（ＮＡＤ）的浓度为１．０４×１０＾－３ｍｏｌ／Ｌ的条件下，其响应电流与葡萄糖浓度在１．０×１０＾－４～３．２×１０＾－３ｍｏｌ／Ｌ范围内有良好线性关系，响应时间为２０ｓ；检测限为４．０×１０＾－５ｍｏｌ／Ｌ。该传感器     

新型安培检测毛细管电泳微系统

将电极、６ｃｍ分离毛细管、缓冲池、检测池集成于８．４×５．０ｃｍ有机玻璃片上,制作了一个毛细管电泳微系统。以碳纤维微盘电极作为工作电极,采用三电极体系柱端检测了１×１０－４ｍｏｌ／Ｌ多巴胺（ＤＡ）,具有良好的重现性,检测限３．６×１０－８ ｍｏｌ／Ｌ,线性范围５×１０－７～１×１０－４ｍｏｌ／Ｌ,并在该系统上分离了邻苯二酚（ＣＡ）和多巴胺的混合物。     

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。     

甲壳素修饰碳糊电极测定亚硝酸根

报道了一种对ＮＯ－２具有高灵敏度和选择性的碳糊化学修饰电极。该电极由碳粉中加入修饰剂甲壳素制备而成。采用酸性Ｂｒｉｔｏｎ－Ｒｏｂｉｎｓｏｎ广泛缓冲溶液（ｐＨ３．９０）为支持电解质,用１．２×１０－４ｍｏｌ／Ｌ十六烷基三甲基溴化铵（ＣＴＭＡＢ）作吸附剂,对亚硝酸根离子进行阳极溶出伏安法测定,检测限为１．０×１０－９ｍｏｌ／Ｌ。在量浓度为２．０×１０－９～２．０×１０－７ｍｏｌ／Ｌ范围内,峰电流与浓度具有线性关系。此修饰电极可直接富集和测定水样中亚硝酸根的含量,大多数离子对测定无干扰,回收率为９６．０％～１１０．０％。     

四氰基醌二甲烷修饰碳糊电极催化氧化测定多巴胺

以四氰基醌二甲烷（ＴＣＮＱ）作介体,制成ＴＣＮＱ修饰碳糊电极。研究该电极的性能。该电极对多巴胺（ＤＡ）有良好的电催化氧化作用,在ＤＡ浓度６．７５×１０＾－５－６．７５×１０＾－３ｍｏｌ·Ｌ＾－１内。催化电流与ＤＡ浓度呈线性关系,响应时间小于１０ｓ。该电极用于针剂中多巴胺测量,结果较好。     

硅钼杂多阴离子薄膜修饰电极的研究和应用—线性扫描伏安法测定水中可溶性

本研究了以玻碳电极为基体的１：１２硅钼杂多酸根修饰电极的制备及其电化学行为，将１２－ＭＳＡ电极应用于线性扫描伏安法测定天然水中可溶性硅酸盐，结果满意，硅浓度在８．０×１０＾－７－１．７×１０＾－３ｍｏｌ／Ｌ，相对标准偏差（ｎ＝７）为１．８５％，加标回收率为９８．２％－１０３．６％，ＳｉＭｏ１２电极具有优良的选择性和稳定性。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.