毛细管电泳磺丁基-β-环糊精拆分对映体

将平均取代度为３．８的负电性磺丁基－β－环糊精手性添加剂应用于毛细管电泳对映体拆分的研究中。考察了背景电解质pＨ及磺丁基－β－环糊精浓度对手性拆分的影响,应用磺 丁基－β－环糊精拆分八对碱性酸性的药物对映体。     

β-环糊精及其衍生物手性添加剂HPLC法拆分氯噻酮对映体过程热力学研究

以Me-β-环糊精为手性流动相添加剂,于Lichrospher C18反相柱上建立了氯噻酮对映体高效液相色谱拆分方法,同时改进了β-环糊精、HP-β-环糊精为手性流动相添加剂拆分氯噻酮对映体的色谱条件,并着重研究了在25-45℃范围内Me-β-CD、β-CD和HP-β-CD为手性流动相添加剂拆分氯噻酮对映体的过程热力学并结合手性药物氯噻酮所得的热力学数据对环糊精及其衍生物拆分能力的差异进行了比较和分析。结果表明都属于焓控过程,其拆分能力的不同主要是因为手性添加剂与对映体形成氢键作用、空间位阻效应和立体构象匹配程度存在差异。     

盐酸美西律对映体的毛细管电泳分离

以β－环糊精的两种生物做为毛细管电泳手性分离添加剂，对盐酸美西律的对映体进行了拆分研究。其中，２，６－Ｏ－二甲基β－环糊精可将对映体部分拆分，而２，３，６－Ｏ－三甲基β－环糊精时，可基线分离对映体。研究了两种甲基化β－环糊精的浓度及工作电压对分离的影响。     

以2-O-单取代羟丙基β-环糊精用于毛细管电泳手性分离添加剂

本文研究了一种新的环糊精衍生物2－O－单取代羟丙基β－环糊精做为毛细管电泳手性分离添加剂时，对3种碱性药物对映体；扑尔敏，麻黄碱，心得安的拆分性能。并与β－环糊精，2．6－O－二甲基β－环糊精，多取代2－O－羟丙基β－环糊精的手性识别性能做了对比。     

以2—O—单取代羟丙基β—环糊精用于毛细血管电泳手性分离添加剂

本文研究了一种新的环糊精衍生物２－Ｏ单取代羟丙基β－环糊精做为毛细管电泳手性分篱添加剂时，对３种碱性药物对映体：扑尔敏，麻黄碱，心得安的拆分性能。     

高效液相色谱手性流动相添加剂法拆分酪氨酸甲酯对映体

分别将β-环糊精、羟丙基-β-环糊精作为手性流动相添加剂，研究了酪氨酸甲酯对映体在反相HPLC系统中的拆分，考察了流动相种类、pH和手性流动相添加剂浓度对手性拆分的影响，建立了β-环糊精手性流动相添加剂法拆分酪氨酸甲酯对映体的方法。     

毛细管电泳环糊精添加剂拆分特布他林对映体的立体选择性研究

分别测定了毛细管区带电泳环糊精手性拆分体系中α,β－环糊精和二甲基、三甲基、羟丙基－β－环糊精与药物对映体特布他林形成包结络合物的稳定常数以及手性拆分过程的热力学函数的变化。数据分析表明,环糊精稳定常数的大小反映了环糊精空腔与分离对象之间的匹配程度。环糊精稳定常数的相对值反映了手性拆分体系的分离能力。两对映体与环糊精所形成包结络合物的Δ（ΔＨ）和Δ（ΔＳ）分别反映了手性拆分过程中立体作用与构象匹配的差异。与甲基化β－环糊精相比,羟丙基－β－环糊精和β－环糊精提供的氢键作用在手性拆分中起着重要作用。     

磺化β-环糊精手性添加剂毛细管电泳对映体拆分的研究

将平均取代度为６．５的负电性磺化β－环糊精手性添加剂应用于毛细管电泳对映体拆分的研究中。在不同电极性条件下,考察了背景电解质ｐＨ值及磺化β－环糊精浓度对手性拆分的影响,并应用磺化β－环糊精拆分酸性,碱性和中性的手性化合物。     

毛细管电动色谱带电环糊精拆分N—FMOC氨基酸对映体

将负电性磺丁基－β－环糊精手性添加剂应用于毛细管电泳氨基酸对映体的拆分研究中,对８种氨基酸对映体与９－芴甲基氧基甲酰氯（ＦＭＯＣ－Ｃｌ）生成的衍生物进行了分离,其中５种得到了基线分离。考察了背景电解质ｐＨ值及磺丁基－β－环糊精的浓度对Ｎ－ＦＭＯＣ氨基酸对映体拆分的影响。     

高效液相色谱手性流动相添加剂分离乳酸对映体

分别将β-环糊精、2,6－二甲基－β－环瑚精和2,3,6－三甲基－β－环糊精作为手性流动相添加剂,系统地研究了D,L-乳酸在反相HPLC系统中的拆分,考察了流动相种类,pH值和手性流动相添加剂的浓度对手性分离的影响,建立了甲基化β-环糊精动态手性固定相分离乳酸对映体的方法。     

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.