流动注射化学发光测定盐酸土霉素

水浴加热后的盐酸土霉素在磷酸介质中,过氧化氢存在下与高碘酸钠反应产生强烈的化学发光。结合流动注射技术建立了一种测定盐酸土霉纱的化学发光新方法。方法的线性范围为１．０＊１０＾－８－６．０＊１０＾－６ｇ／ｍＬ盐酸土霉素。检出限为４．３＊１０＾－９ｇ／ｍＬ,ＲＳＤ为２．５％（Ｃｓ＝２．０＊１０＾－６ｇ／ｍＬ;ｎ＝１１）。     

液相化学发光法测定微量硒

以碘－鲁米诺化学发光反应作指示反应,利用硒（Ⅳ）对Ｃｒ（Ⅵ）－ＫＩ反应的催化作用,提出了测定微量硒的新方法。方法的检出限为２．３＊１０＾－１１ｇ／ｍＬ,线性范围为１．０＊１０＾－１０－１．０＊１０＾－７ｇ／ｍＬ。该方法简单,快速,准确度较高,用于茶叶和人发中硒的测定,结果满意。     

氢化物发生原子荧光光谱法测定临床样品微量砷和硒

研究了氢化物原子荧光法测定临床床样品全血，血清，胎盘，头发，指甲和尿液中微量Ａｓ和Ｓｅ的方法。线性范围为Ａｓ１．３＊１０＾－９－２．５＊１０＾－７ｇ／ｍＬ，Ｓｅ２．８＊１０＾１０－７．５＊１０＾－８ｇ／ｍＬ；相对标准偏差（ｎ＝１３）Ａｓ２．６－３．６％，Ｓｅ２．８－４．２％；Ａｓ、Ｓｅ的标准加入回收率为９６．７－１０４．２％，用于６种临床样品中Ａｓ、Ｓｅ测定，获得满意的结果。     

聚氯乙烯—尼龙6分离富集催化光度法测定痕量金

研究了在稀释酸介质中,痕量金（Ⅲ）催化溴酸钾氧化偶胂Ⅲ褪色的指示反应及其动力学条件,据此建立测定痕量金（Ⅲ）的新方法。方法的检出限为７．９６＊１０＾－１１ｇ／ｍＬ;测定范围为０－１．２＊１０＾－６ｇ／２５ｍＬ。采用聚氯乙烯－尼龙６树脂分离富集样品中的金,用于样品的测定获得满意结果。     

用胶束荧光法监测丹参酮ⅡA的血药浓度

以十二烷基磺酸钠（ＳＬＳ）为胶束试剂,在优化的实验条件下,对兔体血浆中丹参酮ⅡＡ的血药浓度进行了２４ｈ的连续监测,检出限为１．２＊１０＾－９ｇ／ｍＬ,血中丹参酮ⅡＡ的含量在２．８１＊１０＾－６－０．３０＊１０＾－６ｇ／ｍＬ之间。该法简便、灵敏、效果良好。     

用钼酸盐和罗丹明B连续光度法测定铈和钪

聚乙烯醇存在下，铈或钪钼杂多酸与罗丹明Ｂ（ＲＢ）形成离子缔合物，最大吸收均位于５７０ｎｍ，摩尔吸光系数分别为１．１６×１０＾６和５．６２×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，ｃｍ＾－１，０－１．２μｇ／２５ｍＬＣｅ和０－２．０μｇ／ｍＬＳｃ服从比耳定律，检测限１．５ｎｇ／ｍＬＣｅ（ｎ＝１０）和１．１ｎｇ／ｍＬＳｃ（ｎ＝９）。缔合物的摩尔比为Ｃｅ：ｍＯ：ＲＢ＝１：６：３和 Ｓｃ：Ｍｏ：ＲＢ＝１：１     

全固定化试剂流动注射化学发光测定铜

采用离子交换固定法把Ｌｕｍｉｎｏｌ（Ｌｕ），ＣＮ＾－固定在阴离子交换树脂上，串入流动注射系统中，当一定量洗脱剂被注入阴离子交换柱时，洗脱下来的Ｌｕ和ＣＮ＾－与分析物Ｃｕ＾２＋发生化学反应，产生化学发光，实现对Ｃｕ＾２＋的在线检测。本法检出限为１．３×１０＾－９ｇ／ｍＬ，线性范围为４．０×１０＾－９－６．０×１０＾－６ｇ／ｍＬ，ＲＳＤ为３．４％，单次测定在１ｍｉｎ内能完成。已用于井水中铜的测定，结果     

偶合反应化学发光法测定痕量银的研究——K4Fe（CN）6—Luminol体系

将Ａｇ（Ｉ）催化Ｋ４Ｆｅ（ＣＮ）６的水合反应与Ｌｕｍｉｎｏｌ同Ｃｕ（ＣＮ）＾２－４的化学发光反应相偶合，建立起一种新的灵敏测定痕量银的化学发光分析法，在所研究的优化条件下，该法测定银的选择性较好，检测限达到４．０×１０＾－１３ｇ／ｍＬＡｇ线性浓度范围为１．０×１０＾－１２～１．０×１０＾－６ｇ／ｍＬＡｇ对４×１０＾－１１ｇ／ｍＬＡｇ（Ｉ）溶液连续１１次测定的ＲＳＤ≤３．５％，用于环境水和岩矿中银的     

巴比妥酸—NO2^—2铁（Ⅱ）—CPB显色体系光度测定巴比妥酸的研究

本文对巴比妥酸－ＮＯ＾－２－铁（Ⅱ）－ＣＰＢ显色体系进行了研究,建立了一种测定巴比妥酸的分光光度法,该法巴比妥酸含量在１．０＊１０＾－６－２．０＊１０＾－５ｇ／ｍＬ范围内符合比尔定律。     

高效液相色谱法测定中成药金水清中蜕皮甾酮的研究

本文采用反相色谱液相色谱法（ＲＰ－ＨＰＬＣ）,Ｓｈｉｍ－ｐａｃｋ ＣＬＣ－ＯＤＳ柱,甲醇－水（４０：６０）流动相,在２４８ｎｍ波长处测定中成药金水清中蜕皮甾醇的量。在０．５￣１０００μｇ／ｍＬ范围呈线性关系,相关系数为０．９９９８;方法的检出限为０．１０８ｍｍｏｌ·Ｌ＾－１（Ｓ／Ｎ＝３）,ＲＳＤ为０．６６％（ｎ＝７,Ｃ＝１０．０μｇ／ｍＬ）,采用活性氧化铝柱预分离,以除去主要干扰组分的影响。方法简     

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.