痕量尼莫地平测定的紫外薄层色谱扫描法

以Ｖ氯仿∶Ｖ甲醇∶Ｖ二氯甲烷∶Ｖ正己烷＝２．６∶１．２∶１∶５为展开剂，建立了薄层色谱扫描法测定痕量药物尼莫地平的新方法。其Ｒｆ值为０．４８。扫描波长为３６５ｎｍ，该法的最低检出限为０．００５μｇ，相对标准偏差为２．９４％，工作曲线的线性范围为０．００５～１μｇ。用该法测定了加有尼莫地平的血清和尿样，尼莫地平的平均回收率为９６．７％～１０３％。     

同时测定体液中咖啡因和茶碱的薄层色谱扫描法

研究了同时测定血清、尿样中的咖啡因和茶碱的薄层色谱定量法。在ＧＦ２５４硅胶板上，用乙酸乙酯－氨水（Ｖ乙酸乙酯∶Ｖ氨水＝９６∶４）的二元展开体系能将这两种生物碱有效地分离。其Ｒｆ值为咖啡因０．４６，茶碱０．１６。分离后的试样用薄层色谱扫描仪进行扫描定量，测定波长２７２ｎｍ，线性范围咖啡因０．００９７～１．９４μｇ，茶碱０．００９０～１．８０μｇ。血清及尿样的加标回收率在９５．８％～１０６．５％之间，相对标准偏差２．９５％～３．５０％。本法较为简便、快速、准确     

用铬天青S－溴化十六烷基吡啶胶束增溶分光光度法测定头发中的铝

讨论了用ＣＡＳ－ＣＰＢ胶束增溶比色法测定头发中铝含量的最佳实验条件。最大吸收波长为６３０ｎｍ，铝的线性范围为０～４．０μｇ，变异系数ＣＶ＝３．２％（ｎ＝６），回收率为９８％。     

用铬天青S—溴化十六烷基吡啶胶束增溶分光光度法测定头发中的铝

讨论了用ＣＡＳ－ＣＰＢ胶束增溶比色法测定头发中铝含量的最佳实验条件，最大吸收波长为６３０ｎｍ，铝的线性范围为０￣４．０μｇ，变异系数ＣＶ＝３．２％（ｎ＝６），回收率为９８％。     

薄层色谱法检测甘薯呋喃萜类毒素

甘薯呋喃萜类毒素是甘薯受到损害后产生的强制性代谢产物,可用乙醚提取。乙醚提取物分别用５％Ｎａ２ＣＯ３和蒸馏水洗涤,无水硫酸钠干燥,蒸去乙醚。残渣（粗品）采用薄层色谱法进行检测,以纯品甘薯酮和甘薯酮醇作标样。结果表明：在２０℃条件下,在石油醚－醋酸乙酯（２１,Ｖ／Ｖ）和苯－甲醇（９１,Ｖ／Ｖ）两种溶剂系统中,对甘薯酮（Ｃ）、甘薯酮醇（Ａ）、化合物Ｂ和Ｄ的呋喃萜类毒素具有较好的分离效果,Ｒｆ值的重复性也较好。展开后的薄层板可以通过ＣＳ－９３０ＴＬＣ扫描仪在５２７ｎｍ下扫描定量。     

双波长薄层色谱扫描法测定感冒通片中扑尔敏的含量

本文采用双波长薄层扫描仪，以紫外吸收方式，测定了感冒通片中扑尔敏的含量，其测定波长λｓ＝２６０ｎｍ，参比波长λＲ＝３２０ｎｍ，所用薄层板为ＧＦ２５４，薄层厚度为０．４ｍｍ，展开剂为苯∶氯仿∶冰ＨＡＣ∶甲醇＝５∶５∶０．５∶０．６，回收率为１０１．６％。     

对土壤及玉米植株中均三氮苯类除草剂的残留分析

土壤或玉米植株样品用Ｖ（甲醇）∶Ｖ（乙腈）＝１∶１提取,提取液用石油醚净化后,浓缩液过Ｃ１８小柱净化,最后用Ｎｏｖａ－ＰａｋＣ１８柱进行ＨＰＬＣ分析。回收率：氰草津为８２．４％～９９．８％,莠去津为８５．６％～１０２．３％,西草净为８９．１％～１０８．４％。     

噻利洛尔的吸附伏安行为

在ＮＨ３－ＮＨ４Ｃｌ底液中,噻利洛尔在汞电极上有一线性扫描还原峰,电位Ｅｐｃ＝－１．３１Ｖ（ｖｓ,Ａｇ／ＡｇＣｌ）,该峰具有明显的吸附性。当ＣＥＬ浓度较小时,扫描较快,搅拌富集时间较长时,电极反应完全为吸附态的ＣＥＬ的还原所控制,吸附粒子为ＣＥＬ中性分子,测得ＣＥＬ在汞电极上的饱和肿附量为１．０３×１０＾－１０ｍｏｌ／Ｌ,每个ＣＥＬ分子所占电极面积为１．５７ｎｍ＾３,ＣＥＬ在悬汞电极上的吸附符合Ｌ     

Ag/La0.6Sr0.4MnO3基催化剂上CH3OH和CO的完全氧化

合成了Ａｇ／Ｌａ０．６Ｓｒ０．４ＭｎＯ３、Ａｇ／Ｌａ０．６Ｓｒ０．４ＭｎＯ３／γ－ＡＩ２Ｏ３两毓催化剂,发现钙钛矿型Ｌａ０．６Ｓｒ０．４ＭｎＯ３对低浓度ＣＨ３ＯＨ或ＣＯ的完全氧化显示出相当高的催化活性,适量Ａｇ对钙钛矿型Ｌａ０．６Ｓ５０．４ＭｎＯ３基质的修使其对ＣＨ３ＯＨ或ＣＯ完全氧化催化活性获明显提高;在６％Ａｇ／２０％Ｌａ０．６Ｓｒ０．４ＭｎＯ３／γ－ＡＩ２Ｏ３催化剂 ,ＣＨ３ＯＨ完全氧化的Ｔ     

泡沫塑料吸附—溶出计时电位法测定地质物料中痕量铊

本文提出了泡沫塑料吸附解脱新体系，建立了泡沫塑料吸附－溶出计时电位法测定地质物料中痕量铊的新方法。方法检出限０．０３μｇ／ｇ；铊的含量水平分别为０．７１μｇ／ｇ和１．６μｇ／ｇ时的测定精密度为３．４５％和３．２８％；工作曲线线性范围为５￣１５００ｎｇ／ｍＬ；回收率为９７．５％￣９８．０％。     

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.