毛细管区带电泳法测定尿中甲酸含量

采用高效毛细管区带电泳法测定人体尿中甲酸含量,尿样经过滤后直接进样,方法简单、快速,测定结果令人满意。电泳电解质体系采用５ｍｍｏｌ／Ｌ邻苯二甲酸氢钾,０．５ｍｍｏｌ／Ｌ十六烷基三甲基溴化铵,ｐＨ６,５０ｃｍ×５０μｍｉ．ｄ．熔融石英毛细管（有效长度４８．５ｃｍ）,检测波长２１０ｎｍ,负电源,分离电压３０ｋＶ,压力进样,恒温２５℃,每次电泳前用０．１ｍｏｌ／ＬＮａＯＨ及缓冲溶液对毛细管各冲洗５ｍｉｎ。同时,采用检测波长与参比波长对调的方法使负峰转变为正峰。     

九种嘌呤碱的毛细管区带电泳分离

用毛细管区带电泳法分离和测定咖啡碱，９－Ｎ二羟丙基茶碱，可可碱，腺嘌呤，鸟嘌呤、茶碱、黄嘌呤、尿酸和６－巯基嘌呤，在熔硅毛细管（７０ｃｍ×７５μｍｉ．ｄ，有效长度６３ｃｍ）内，使用０．０１ｍｏｌ／Ｌ（ｐＨ＝１０）硼砂缓冲溶液，电压为２５ｋＶ温度为３０℃，真空进样１ｓ，于２６０ｎｍ处检测，可在７ｍｉｎ内分离上述到９种嘌呤碱，理论塔板数达到３．０×１０＾５，检测限达ｆｍｏｌ级，方法用于人尿分析，结果令     

毛细管区带电泳分离和测定嘧啶碱

本报道毛细管区带电泳分离和测定胞嘧啶，胸腺嘧啶，尿嘧啶，羟乙基氟尿嘧啶，尿嘧啶丙酸和５－氟尿嘧啶，在熔硅毛细管（７０ｃｍ×７５μｍｉ，ｄ，有效长度６３ｃｍ）上，以０．０１ｍｏｌ／Ｌ硼砂缓冲溶液（ｐＨ＝９．２５）作电解质，电压为２０ｋＶ，温度为３５℃，真空进样１ｓ，于２７０ｎｍ处检测，可在８ｍｉｎ内完全分离上述６种嘧啶碱，塔板数达到２．５×１０＾５，碱基检测限为（０．９～３．６）×１０＾－６ｍｏｌ     

吸附伏安法测定中草药中的钼

叙述了测定痕量钼的一种灵敏的吸附伏安法。本法以钼（Ⅵ）和茜素红络合物在悬汞电极上的吸附行为为基础，在０．０１ｍｏｌ／ＬＮａＡｃ、０．０８ｍｏｌ／ＬＨＡｃ和１．５×１０－６ｍｏｌ／Ｌ茜素红底液条件下，该体系１．５、２．５阶微分吸附伏安法的线性范围是７．５×１０－１１～７．５×１０８ｍｏｌ／Ｌ；对２．５阶微分吸附伏安法，富集３ｍｉｎ的检测下限是５×１０－１１ｍｏｌ／Ｌ。用此法直接测定了中草药中的痕量钼。     

复方新诺明片剂中有效成分的毛细管区带电泳快速测定法

研究了用毛细管区带电泳法快速测定复方新诺明片中磺胺甲恶唑（ＳＭＺ）和甲氧苄氨嘧啶（ＴＭＰ）的含量。使用长２７ｃｍ（有效长度２０ｃｍ）内径５０μｍ的石英毛细管,２５ｋＶ分离电压,在０．０５ｍｏｌ／Ｌ的乙酸盐缓冲液（ｐＨ５．５）中,上述两组分可在１．５ｍｉｎ内完全分离。用紫外检测器在２１４ｎｍ处检测,外标法定量。１０次检测含有１４１．７ｍｇ／ＬＳＭＺ和２５．６ｍｇ／ＬＴＭＰ的试样溶液,相对标准偏差为１     

毛细管电泳在拮抗药物对氨基苯甲酸，对羟基苯甲酸和磺胺分析测…

本报道了一种用毛细管区带电泳法分离与测定对氨基苯甲酸、对羟基苯甲酸及磺胺类药物的新方法。电泳条件为：用２０ｍｍｏｌ／Ｌ硼砂－２０ｍｍｏｌ／ＬＨ３ＰＯ４－２０ｍｍｏｌ／Ｌβ－环糊精－４％乙醇作电泳液，Ｌ－抗坏血酸为内标，２８０ｎｍ为检测波长，样品由电进样方式１０ｋＶ／１０ｓ）引入毛细管（５１．２ｃｍ×５０μｍｉ．ｄ．，有效分离长度为３８．５ｃｍ）．在２４．５℃下，６ｍｉｎ内三可达基线分离（电泳电     

铂—钯共显色衍生络合物的高效液相色谱研究

研究了Ｐｄ（Ⅱ）和４，４＇－二（二乙氨基）苯硫酮（ＢＤＰＴＫ）共显色所生成的Ｐｔ（Ⅱ）络合物，于Ｎｕｃｌｅｏｓｉｌ Ｃ８柱上，用含３×１０＾－３ｍｏｌ／Ｌ ＣＳＡ和０．０２ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ（ｐＨ３．５）的乙腈－丙酮－水（７２：５：２３，Ｖ／Ｖ）作流动相（１．０ｍｌ／ｍｉｎ）分离并检测。Ｐｔ的校正曲线的线性范围为０．２～３．０μｇ／ｍｌ，Ｐｔ检测限为０．７ｎｇ。此方法已应用于抗癌药物顺铂     

铂－锇共显色衍生配合物的高效液相色谱研究

研究了Ｏｓ（Ⅱ）和４，４’二（二乙氨基）苯硫酮与Ｐｔ（Ⅱ）共显色所衍生的配合物，于ＮｕｃｌｅｏｓｉｌＣ＿８柱上，用含３×１０￣（－３）ｍｏｌ／ＬＤＬ－樟脑－１０－磺酸和０．０２ｍｏｌ／ＬＨＡｃ－ＮａＡｃ（ｐＨ３．５）的乙腈－丙酮－水（７２：５：２３，Ｖ／Ｖ）作流动相（１．０ｍＬ／ｍｉｎ）分离并检测。线性范围为０．２～４．０μｇ／ｍＬＰｔ；检测限为１．０ｎｇＰｔ。此方法已应用于抗癌药物顺铂和卡铂的分析。     

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。     

微乳液的增敏作用研究──Ni（Ⅱ）－5－Br－PADAP的分光光度法测定

以含水量８０％的阴离子型ＳＤＳ／ｎ－Ｃ＿（５）Ｈ＿（１１）ＯＨ／ｎ－Ｃ＿（７）Ｈ＿１６／Ｈ＿（２）Ｏ微乳液为介质，进行了Ｎｉ（Ⅱ）－５－Ｂｒ－ＰＡＤＡＰ的分光光度研究，其表观摩尔吸光系数为１．１３×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），与相应含水量的ＳＤＳ胶束介质比较，测定的灵敏度显著提高（后者为７．５×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）），样品分析结果令人满意。     

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.     

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.     

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.