氧氟沙星—镁络合吸附波的研究

本文用多种电化学方法研究了氧氟沙星与镁离子的相互作用及其极谱伏安行为，在０．０１ｍｏ１／Ｌ的ＮＨ３－ＮＨ４Ｃ１缓冲溶液中（ｐＨ＝９．２），氧氟沙星与镁离子络合，产生一灵敏的还原峰，峰电位ＥＰ＝－１．７０Ｖ（ｖｓ．Ａｇ／ＡｇＣｌ）．该峰为不可逆的络合吸附峰，还原峰电流与镁离子浓度在４×１０－６～２×１０－５ｍｏｌ／Ｌ范围内呈良好的线性关系，可望用于镁离子的分析测定．本文还测定了该络合物的络合比，探讨了电极反应机理与络合物结构．     

多菌灵在玻碳电极上的伏安行为及其应用

应用循环伏安法、微分脉冲伏安法对多菌灵在破碳电极上的电化学行为及其测定进行了研究。在ｐＨ＝９．０的２ｍｏｌ／Ｌ ＮＨ３－ＮＨ４Ｃｌ底液中，对其进行循环伏安扫描，发现于０．６１Ｖ（ｖｓ．Ａｇ／ＡｇＣｌ）产生一灵敏的氧化峰。微分脉冲伏安法殉菌灵的检测限为４×１０＾－８ｍｏｌ／Ｌ。多菌灵的浓度在５．０×１０＾－７￣１．０×１０＾－５ｍｏｌ／Ｌ间与微分脉冲伏安峰电流呈线性关系（ｒ＝０．９９４２）。对于１×     

头孢唑啉降解产物在银亚微盘电极上的电化学行为及其测定

基于头孢唑啉在 ０．１０ｍｏｌ／Ｌ ＮａＯＨ溶液中水浴降解产物中含有巯基（－ＳＨ），在 ｐＨ ５．０ＮａＡｃ－ＨＡｃ介质中，于银亚微盘电极上产生一灵敏的吸附伏安氧化还原峰，其峰电位分别为 Ｅｐａ＝－０．５３０Ｖ和 ＥＰｃ＝－０．４００Ｖ。动力学研究表明：电极反应的电子转移数为０．９１，表观电子传递速率为ｋｓ＝０．１０ｓ－１，峰电流与头孢唑啉浓度在１．０×１０－６～５０×１０－１ｍｏｌ／Ｌ范围内呈良好的线性关系。方法可应用于人工合成样品头孢啉的检测。     

一种基于形成杂多核络合物的荧光增敏效应的研究：Ⅲ.锰（Ⅱ）,钴（…

本研究了Ｍｎ＾２＋和Ｃｏ＾２＋对７－（８－羟基－３，６－二磺基萘偶氮）－８－羟基喹啉－５－磺酸－硼砂反应体系的混合荧光增敏作用。实验条件下，荧光增敏强度满足线性加和关系的范围是：Ｍｎ＾２＋浓度０￣２．９×１０＾－７ｍｏｌ／Ｌ；Ｃｏ＾２＋浓度０￣８．８～１０＾－７ｍｏｌ／Ｌ；总浓度不超过１．０×１０＾－６ｍｏｌ／Ｌ。检出限量为Ｍｎ＾２＋４．５×１０＾－９ｍｏｌ／Ｌ和Ｃｏ＾２＋１．４×１０＾－８ｍｏ     

钒－槲皮素－氯酸盐体系极谱催化波的研究

在醋酸盐缓冲底液中，钒能与槲皮素形成络合物，并吸附在汞电极上，在氯酸盐存在下，在Ⅴ（Ⅳ）还原至Ⅴ（Ⅲ）过程中，形成催化波。用单扫二阶导数极谱法测定时，钒浓度在１．０×１０￣（－９）～５．０×１０￣（－６）ｍｏｌ／Ｌ与峰高有正比关系，检出下限为５．０×１０￣（－１０）ｍｏ１／ｍＬ。测得电活性络合物的组成为Ⅴ（Ⅳ：Ｑｕ＝１：２。平行催化反应的速率常数Ｋ＝１．５×１０￣（４）（ｍｏｌ／Ｌ）￣（－１）ｓ（－１）。     

过硫酸钾存在下人血清白蛋白的极谱平行催化氢波及其应用

报道 Ｋ２Ｓ２Ｏ８存在下人血清白蛋白（ＨＳＡ）的极谱平行催化氢波。在 ０．４ ｍｏｌ／Ｌ　ＮＨ３－ＮＨ４Ｃｌ（ｐＨ ８．５８）－０．０１ ｍｏｌ／Ｌ Ｋ２ｓ２Ｏ８支持电解质中，ＨＳＡ产生一个平行催化氢波，峰电位为－１．８５ Ｖ（ｖｓＡｇ／ＡｇＣｌ）。该平行催化氢波二阶导数峰电流与 ＨＳＡ浓度在 ２．６ × １０－９～９．６ × １０－９ｍｏｌ／Ｌ范围呈线性关系。用于人血清样和尿样中ＨＳＡ的测定，结果满意。     

锡钨杂多酸-耐尔蓝光度法测定纳克量锡

本文报道一个光度法测定纳克量锡的新方法。在聚乙烯醇（ＰＶＡ）存在下锡（Ⅳ）与钨酸盐和耐尔蓝（ＮＢ）反应形成离子缔合物,离子缔合物的最大吸收位于５８０ｎｍ,表观摩尔吸光系数ε值２．９５×１０７Ｌ·ｍｏ１－１·ｃｍ－１,服从比耳定律范围０～２．０μｇ／Ｌ,检出限（３σ）０．０８３μｇ／Ｌ（ｎ＝１０）,对２．０μｇ／Ｌ锡测定的ＲＳＤ为１．４２％（ｎ＝１１）,离子缔合物至少稳定７２ｈ。考察了４０多种共存离子的影响,大多数常见元素不干扰。测定锡的适宜条件［Ｈ２ＳＯ４］＝１．２０ｍｏ１／Ｌ,［ＷＯ２－４］＝６．０５×１０－５ｍｏ１／Ｌ,［ＮＢ］＝５．５×１０－５ｍｏ１／Ｌ和ＰＶＡ０．０８％。本法已用于某些合金钢和锌合金中纳克量锡的测定,结果与推荐值吻合,回收率满意。     

新化学发光试剂ITCI的合成及其性能研究

合成一种新化学发光试剂异硫氰酸异鲁米诺（ＩＴＣＩ），研究其化学发光及标记酵母ＲＮＡ的性能。标记反应条件温和快速，１克酵母ＲＮＡ可与１．５×１０－５ｍｏｌＩＴＣＩ结合。建立了测定ＩＴＣＩ和ＲＮＡ的化学发光分析方法，线性范围分别为１．０×１０－１０～１．０×１０－７ｍｏｌ／Ｌ和４．０～×１０－９～２．０×１０－７ｇ／ｍＬ，检测限分别为６．６×１０－１１ｍｏｌ／Ｌ和８．０×１０－１０ｇ／ｍＬ。     

Fe（Ⅲ）－TEA－5－Br－PADAP－H_2O_2体系中催化波的研究及其应

在０．２ｍｏｌ·Ｌ￣（－１）ＮＨ＿４Ｃｌ－ＮＨ＿３·Ｈ＿２Ｏ底液中，（ｐＨ为９．２６），得到一个极为灵敏的Ｆｅ（Ⅲ）－ＴＥＡ－５－Ｂｒ－ＰＡＤＡＰ－Ｈ＿２Ｏ＿２配合吸附催化波，其峰电位为－０．７１Ｖ（ｖｓ．ＳＣＥ）。铁浓度在１．８×１０￣（－１０）～５．４×１０￣（－６）ｍｏｌ·Ｌ￣（－１）范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究，证明是一种配合吸附催化波，并成功地应用于各类水样，钒催化剂中微量或痕量铁的测定。     

聚乙烯醇与4-乙烯基吡啶和丙烯酰胺的共接枝物凝胶用于制备葡萄糖生物传感器

在聚乙烯醇长链骨架上接枝４－乙烯基吡啶和丙烯酰胺合成得三元接枝物，采用这种三元接枝物凝胶固定葡萄糖氧化酶制备了葡萄糖传感器。该酶电极响应时间为７～１０ ｓ；电流密度在０．６５ Ｖ（ｖｓ． Ａｇ／ＡｇＣｌ）；对１ｍｍｏｌ／Ｌ葡萄糖可达到４８０ ｎＡ／ｍｍ２，其线性范围为５×１０－６～５×１０－３ｍｏｌ／Ｌ，使用两个月后响应仍在８５％左右。     

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%.     

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.     

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.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

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.