Mo（Ⅵ）－PAN与Mo（Ⅵ）－PAR体系的极谱性质对比研究

本文比较了Ｍｏ（Ⅵ）－１－（２－吡啶基偶氮）－２－萘酚（ＰＡＮ）与Ｍｏ（Ⅵ）－４（２－吡啶基偶氮）间苯二酚（ＰＡＲ）的极谱性质，讨论它们在作为吸附波试剂时的优缺点，以求得在选择络合剂时的感性和理性认识．本文还报道了Ｍｏ（Ⅵ）－ＰＡＮ－ＫＢｒＯ３吸附催化波体系，最佳实验条件，０．１ｍｏｌ／ＬＨＡｃ－－ＮａＡｃ，ｐＨ＝４．６，０．０１ｍｏｌ／ＬＫＢｒＯ３，２．５×１０－５ｍｏｌ／ＬＰＡＮ．峰电位为－０．７１Ｖ（ｖｓ．ＳＣＥ），检出限１×１０－９ｍｏｌ／Ｌ，线性范围０～６×１０－７ｍｏｌ／Ｌ     

镓,铟与酸性铬深蓝络合物吸附波的研究及其应用

在醋酸盐缓冲溶液中，用单扫示波极谱法分别获得了镓（Ⅲ）、铟（Ⅲ）与酸性铬深蓝灵敏的络合物吸附波。两个波的峰电位分别为－０５１Ｖ和－０６３Ｖ（ｖｓＳＣＥ），镓（Ⅲ）的线性范围为７２０×１０－７～７４６×１０－６ｍｏｌ／Ｌ；铟（Ⅲ）为１７４×１０－７～４８８×１０－６ｍｏｌ／Ｌ。作者研究了该电极反应机理。该法用于矿石中镓、铟的测定，结果满意。     

哌仑西平的单扫描示波极谱法测定

本报道一种测定哌仑西平的单扫描示波极谱法，在０．１ｍｏｌ／ＬＮＨ４Ｃｌ－ＮＨ３．Ｈ２Ｏ（ｐＨ８．０±０．１）缓冲液中，哌仑西平有一极谱还原波，其峰电位为－１．５１Ｖ（ｖｓ．ＳＣＥ），其一阶导数峰高与哌仑西闰浓度在６．６×１０＾－７－４．６×１０＾－６ｍｏｌ／Ｌ（ｒ＝０．９９８１）和６．６×１０＾－６－１．６×１０＾－５ｍｏｌ／Ｌ（ｒ＝０．９９９１）范围内有线性关系，检测限为３．４×１０－７ｍｏｌ     

氧氟沙星的单扫描示波极谱分析

报道了一种灵敏的氧氟沙星测定方法－一阶导数单扫示波极谱分析，同时研究了它的极谱波性质和电极反应机理，在ｐＨ６．０的ＫＨ２ＰＯ４－Ｎａ２ＨＰＯ４（ＰＢＳ）底液中，氧氟沙星产生一个灵敏的还原峰，Ｅｐ＝－１．５５Ｖ（ｖｓ．ＳＣＥ），其导数峰高与浓度在１．０×１０＾－５～４．６×１０＾－７ｍｏｌ／Ｌ范围内呈良好的线性关系，相关系数ｒ＝０．９９９６，检测下限为２．４×１０＾－７ｍｏｌ／Ｌ，可用于氧氟沙星片剂     

铜（Ⅱ）锌（Ⅱ）—氟哌酸体系电化学行为及示波极谱法研究

铜（Ⅱ）和锌（Ⅱ）分别在０．１ｍｏｌ／ＬＫＨ２ＰＯ４－Ｎａ２ＨＰＯ４缓冲溶液（ｐＨ６．５）和０．２５ｍｏｌ／ＬＮＨ４Ｃｌ溶液中，与氟哌酸形成良好的络合吸附波，峰电位分别为－０．２６Ｖ和－１．２８Ｖ（ｖｓ．ＳＣＥ），络合比分别为１：３和１：２，峰电流与铜（Ⅱ）和锌（Ⅱ）的浓度均在４．０×１０＾－７～５．０×１０＾－６ｎｏｌ／Ｌ范围内呈线性关系，检测限分别为７．０×１０＾－８和５．０×１０＾－８ｍｏｌ     

筛选免疫药物的单扫描示波极谱法研究

用示波极谱研究了溶血素的溶血活性，在１／１５ｍｏｌＬＮａＨＰＯ４－１．１５ｍｏｌ．ＬＫＨ２ＰＯ（ｐＨ＝７．４）底液中活性溶血素有一灵敏的极谱阴极波，峰电位为－１．８２Ｖ，峰高与溶血素活性在６．０＊１０＾－６－５。３＊１０＾－５ｕｎｉｔ．ｍＬ和５．３＊１０＾－５－２。０＊１０＾－３ｕｎｉｔ／ｍＬ范围内呈线性关系，根据不同药物对抗血清中溶血清形成的不同影响，建立了极谱法筛选免疫药物的新方法。本法简单，     

扑尔敏的示波极谱测定

在０．１ｍｏｌ／Ｌ的Ｈａｃ－ＮａＡｃ缓冲溶液中，扑尔敏于—１．３６Ｖ（ｖｓ．ＳＣＥ）处产生一灵敏的极谱还原波，导数波高与扑尔敏在２．０×１０~（－６）～８．０×１０~（－５）ｍｏｌ／Ｌ浓度范围内成线性关系，检测下限达６．０×１０~（－７）／ｍｏｌ／Ｌ。对极谱波的性质进行了探讨，并用该法测定了速效伤风胶囊中扑尔敏的含量。     

锗(Ⅳ)-邻苯二酚紫-钒(Ⅳ)体系的极谱吸附催化波研究

在０．１ｍｏｌ／ＬＨ２ＳＯ４溶液中，Ｇｅ（Ⅳ）－邻苯二酚紫（ＰＶ）－Ｖ（Ⅳ）体系产生一灵敏的吸附催化波，峰电位在－０．５５Ｖ（ｖｓ．ＳＣＥ）处．锗浓度在２．２×１０－１０～２．８×１０－６ｍｏｌ／Ｌ范围内与峰电流呈线性关系．检出限为１．１×１０－１０ｍｏｌ／Ｌ．研究了极谱波的性质．本法用于土壤中痕量锗的测定，结果满意．     

青藤碱和黄芩甙的极谱特性

用单扫示小极谱法研究了青藤碱和黄芩甙的电化学行为，青藤碱在０．１ｍｏｌ／Ｌ Ｎａ２Ｂ４Ｏ７中有两个还原峰，峰Ｐ１和Ｐ２的电位分别为－１．４５Ｖ和－１．６７Ｖ，峰Ｐ１的峰电流与浓度在０．０６－１．８ｍｇ／Ｌ和２．０－３４．６ｍｇ／Ｌ范围内呈线性关系，检测限为０．０２ｍｇ／Ｌ，在０．０５ｍｏｌ／Ｌ棕檬酸钠＋０．２ｍｏｌ／Ｌ ＨＣｌ底液中，黄芩甙于－１．１４Ｖ（Ｐ３０和－１．３２Ｖ（Ｐ４）处产生两还原峰     

碘酸钾存在下极谱催化波法测定陈皮甙

基于陈皮甙在ＫＩＯ３存在下产生的极谱催化波，拟定了测定陈皮甙的新方法。在 ０．５５ ｍｏｌ／Ｌ ＨＡｃ－０．０１ｍｏｌ／Ｌ　ＮａＡｃ（ｐＨ ４．００±０．０５）－１．０×１０～（－３）ｍｏｌ／Ｌ ＫＩＯ３缓冲溶液中，陈皮甙催化波的峰电位为－１．３５ Ｖ（ｖｓ，ＳＣＥ），它的一阶导数峰峰电流与陈皮甙浓度在２．６ × １０～（－７）～２．６ × １０～（－６）ｍｏｌ／Ｌ范围内呈线性关系（ｒ＝０．９９７０，ｎ＝６）。本方法比现有的电化学方法灵敏度高一个数量级。可用于直接测定中草药贯众水提液中陈皮甙含量。     

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.     

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.     

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.     

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.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

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.