盐酸小檗碱-十二烷基苯磺酸钠缔合微粒体系的共振散射光谱研究及其分析应用

在pH 4 .80NaAc HAc缓冲介质中 ,盐酸小檗碱 (BH)与十二烷基苯磺酸钠 (DBS)由于静电引力和疏水作用力形成缔合微粒 ,在 4 70nm处有一共振散射峰。随着DBS浓度增大 ,该峰急剧增强 ,即存在缔合微粒的散射光增强效应 ;345nm处的吸光度减弱 ,即存在缔合微粒的减色效应。研究了共振散射光谱测定BH的影响因素 ,提出了测定 (0 .35～ 4 .4 )× 10 -5mol/L盐酸小檗碱的共振散射光谱新方法 ,用于复方黄连素片剂和针剂样品的测定 ,结果满意     

HAS-硅钨杂多酸缔合纳米微粒体系的荧光猝灭

人血清白蛋白;瑞利散射;HAS-硅钨杂多酸缔合纳米微粒体系的荧光猝灭     

盐酸苯海拉明和曙红B体系的光谱研究及其分析应用

在pH 3.1的Britton-Robison缓冲介质中,曙红B与盐酸苯海拉明借助静电引力和疏水作用力形成离子缔合物,使最大散射波长为364 nm处的共振光散射光谱得到加强。研究了体系的共振光散射光谱和紫外-可见吸收光谱。建立了一种测定盐酸苯海拉明的新方法。体系共振光散射增强的强度与盐酸苯海拉明的质量浓度在0.5~11.2 mg/L范围内呈现良好的线性关系,方法的检出限为41.7μg/L。可用于药物中盐酸苯海拉明的测定。     

12-钨磷酸共振瑞利散射光谱法测定盐酸苯海拉明

在pH值为0～1.5范围内,12-钨磷酸与盐酸苯海拉明(DP.HCl)反应形成缔合物后引起共振瑞利散射(RRS)强度显著增强,最大散射峰位于305nm,散射强度与DP.HCl浓度在8.0×10-9～1.6×10-6g/mL范围内成线性关系,据此建立了测定盐酸苯海拉明的RRS法。本法具有较高的灵敏度和良好的选择性,其检出限(3σ)为0.8×10-9g/mL。用于尿样中盐酸苯海拉明的测定,回收率为96.0%～104.2%。结合量子化学AM1法计算结果讨论了反应机理。     

停流流动注射在线沉淀-原子吸收法测定盐酸苯海拉明

本文建立了一种简单快速的检测药剂中盐酸苯海拉明含量的停流流动注射在线沉淀 间接原子吸收法。该方法是基于盐酸苯海拉明与BiI-4在线定量连续生成离子对缔合物沉淀(摩尔比为1∶1),经停流过滤稀释后,以AAS法测定滤液中铋的含量来间接测定盐酸苯海拉明的量。本法的相对平均偏差小于3.5%,线性范围为2.5～40μg·mL-1,采样频率60h-1,回收率为98%～103%。     

西替利嗪-碘铂酸缔合微粒体系的吸收光谱研究及分析应用

Pt(IV)与I-形成[PtI6]2-,[PtI6]2-和盐酸西替利嗪(CTRZ)通过静电引力作用形成疏水性的(PtI6—CTRZ)缔合物分子.由于(PtI6-CTRZ)缔合物分子间存在较强的分子间作用力和疏水作用力而生成紫红色(CTRZ—PtI6)n缔合微粒,在310、400、610nm处产生3个共振散射峰;在350～740nm波长范围的吸光度值均增大.在选定条件下,CTRZ浓度在0～10μg/mL范围内与A580nm成正比,摩尔吸光系数ε580nm为1.30×104L/(mol·cm).实验结果表明,(CTRZ—PtI6)n缔合微粒的形成是导致同步散射信号增强的根本原因,而纳米纳米微粒的颜色是共振散射所致.     

蛋白质阳离子表面活性剂缔合微粒体系的光谱特性及分析应用

蛋白质阳离子表面活性剂缔合微粒体系的光谱特性及分析应用;阳离子表面活性剂;HAS;缔合微粒;共振散射光谱     

小檗碱-Ⅰ3^-缔合微粒体系的光度分析应用

在稀HCl介质中,I-3在340 nm处有一吸收峰;当小檗碱(BB)与I-3共存时体系呈橙黄色,在580 nm处产生一共振散射峰.以试剂作参比,该缔合微粒体系在530 nm产生一吸收峰,BB浓度在0～7.0×10-5mol/L范围内与A530 nm呈线性,据此建立了一种测定小檗碱含量的分光光度新方法,并用于针剂样品中小檗碱测定,结果满意.同步散射光谱研究表明,BB+与I-3可通过静电引力作用形成疏水性的(I3-BB)缔合物分子,并进一步聚集形成稳定的(I3-BB)n缔合纳米微粒.由于该缔合纳米微粒在580 nm处产生共振散射效应,故体系呈橙黄色.     

罗丹明B-PdI2-4缔合纳米粒子体系的极谱猝灭效应

缔合纳米微粒;共振散射;罗丹明B-PdI2-4缔合纳米粒子体系的极谱猝灭效应     

盐酸苯海拉明的原子吸收法测定

探讨了盐酸苯海拉明在适当的酸性条件下与锌试剂、铜离子定量生成三元络合物,经ＭＩＢＫ萃取,以ＡＡＳ法测定萃取液听 铜来间接测定盐酸苯海拉明的量。本法与药典法相比,相对平均偏差小于０．４％,线性范围为５～５０μｇ．ｍＬ＾－１。回收率为９７％～１０２％。     

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.