双-(2,4-二羟基苯乙酮)缩肼的合成及其与锶的荧光猝灭反应

合成了一种新的双席夫碱荧光试剂——双-(2,4-二羟基苯乙酮)缩肼。该试剂在491．2nm处有强荧光峰,当有锶离子存在时,可形成稳定的络合物而使试剂的荧光猝灭。利用此反应建立了一个荧光测定痕量锶的新方法,其线性范围为0．10—50．0μg/L,检出限0．056μg/L,方法成功地应用于矿泉水中痕量锶的测定。     

DNA荧光探针—荧光素-中性红体系的研究

基于DNA对荧光素(FL)-中性红(NR)分子间荧光能量转移的抑制作用，以荧光素-中性红为荧光探针，考察该探针与DNA的结合反应，建立了准确测定DNA的新方法，在pH＝6.5条件下，hsDNA、ctDNA和smDNA的浓度与荧光素-中性红体系的荧光比值变化量Δ(Fd／Fa)成线性关系，响应线性范围分别为0．25-6．25μg／mL、0．10-5．00μg／mL、0．10-4．00μg／mL，0.025μg/mL和0．023μg／mL；分析测定了DNA合成样品，回收率91．3％-101．4％，相对标准偏差小于4．2％．     

2，3，4-兰羟基苯乙酮缩-2-羧基苯胺与铜的高灵敏度荧光反应及其应用

合成了新荧光试剂2,3，4-三羟基苯乙酮缩-2-羧基苯胺(TAFA)。详细研究了试剂与铜的荧光反应新体系的最佳适宜条件。在pH9．0的乙醇／水(3．5：6．5，V/V)溶液中，该试剂与铜离子形成稳定的络合物，组成比为1：1(金属：试剂)，λex/em=422．4／561．6nm。所建立的铜的荧光分析方法的线性范围为0.5～120.0μg／L；检出限为0．26μg／L。方法成功地应用于矿泉水和水中痕量铜的测定。     

硫酸喹啉荧光猝灭法测定脱氧核糖核酸

基于DNA在pH2～4的范围内对硫酸喹啉的荧光具有较强的猝灭作用，建立了一种测定DNA的新方法。当DNA的浓度为10～700μg／L时，荧光猝灭程度与DNA浓度呈线性关系，其线性回归方程为：△IF=1．52118 0．11038G(μg／L)；相关系数r=0．9985；检出限为5．9μg／L。本方法用于大肠杆菌提取的质粒DNA的测定，获得满意结果。     

新试剂3-对氟苯基-5-（2＇-羧基苯偶氮）若丹宁的合成及荧光法测定铋

合成了新型试剂3-对氟苯基-5．(2’-羧基苯偶氮)若丹宁，并经元素分析、IR确证了其结构。研究发现在pH=5．2时该试剂与痕量铋锄形成的螯合物可使试剂的荧光强度大大减弱，在λex／λem=305nm/404nm处有最大峰；其荧光猝灭值与铋的浓度在1．0-12μg/L范围内呈线性关系，检出限达0．26μ／L。建立了荧光光度法测定痕量铋的新方法。     

联吡啶-铜(Ⅱ)络合物荧光增强法测定核酸

利用联吡啶-Cu(Ⅱ)络合物作为荧光探针测定脱氧核糖核酸(DNA),实验发现加入天然和变性DNA均能使联吡啶-Cu(n)络合物(Cu(bpy)2^2 )体系的荧光强度大幅度增强。测定体系的最大激发和发射波长分别为304和334nm。在最佳实验条件下,测定的线性范围分别为：小牛胸腺(CT-DNA)0．09—9mg／L;鱼精DNA(FS—DNA)0．01—12.5mg／L;酵母DNA(yeastDNA)0．30—35mg／L。检出限分别为0.003、0．002和0．02mg／L。实验结果推测该络合物与DNA之间通过静电作用结合。     

锆—7—（1—苯偶氮）—8—羟基喹啉—5—磺酸—Triton X—100荧光熄灭法测定锆

基于在pH＝4．5～5.5、TritonX－100存在下、锆同7－（1-苯偶氮）－8-羟基喹啉-5-磺酸形成组成比为1：3的黄色络合物使荧光熄灭，建立了荧光熄灭测定锆的新方法。该方法的线性范围为0～28μgZrO2／L，检测限为0．5μg／L，体系稳定，灵敏度高，用于α-βAl2O3及瓷釉中锆的测定，结果满意。     

用银-邻菲啰啉-邻氯苯基荧光酮离子缔合物体系荧光熄灭法测定银

在聚乙烯醇存在下，银与邻氯苯基荧光酮及邻菲啰啉形成离子缔合型异配位体络合物使邻氯苯基荧光酮的荧光熄灭。在pH6．4～7．2的HAc－NH4Ac或NH3·H2O－NH4Ac介质中，λex＝400nm，λem＝550nm，体系的相对荧光强度最大，线性范围为0～500μg／L，检出限为0．013mg／L，方法用于阳极泥中银的测定，结果满意。     

双席夫碱双-(2,4-二羟基苯乙酮)缩肼的合成及其与铜的荧光猝灭反应

报道了一种新的双席夫碱荧光试剂——双—(2，4—二羟基苯乙酮)缩肼的合成；试剂在492.8nm处有一强荧光峰，当有铜离子存在时，可与试剂形成稳定的配合物而使试剂的荧光猝灭；利用此反应建立了一个荧光测定痕量铜的新方法，测定铜的线性范围为0．0～180．0μg／L，检出限0．02μg／L，方法可应用于矿泉水和水中痕量铜的测定。     

环境水样中痕量肼的荧光分析

基于在硫酸介质中，肼与罗丹明6G反应，使其荧光增强，建立了一种荧光测定痕量肼的新方法。该方法线性范围2．0－14．0μg/L，检出限为0．62μg/L。可用于环境水样中肼含量的测定，并进行了回收实验，回收率为97％－107％。     

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.