手性选择体涂敷薄层色谱拆分盐酸普萘洛尔

采用手性选择体涂敷薄层色谱方法,拆分了盐酸普萘洛尔对映体,考察了β-环糊精、羟丙基-β-环糊精以及（2R,3R）-酒石酸-二-烷基酯等多种手性选择体拆分效果,得到手性选择体涂敷薄层色谱拆分盐酸普萘洛尔对映体最佳条件：采用β-环糊精、羟丙基-β-环糊精涂敷薄层色谱,以乙腈-仲丁醇混合溶剂作展开剂,展开剂中乙腈体积分数大于30%时,室温下展开均可拆分盐酸普萘洛尔对映体,并实现基线分离.实验同时发现,采用（2R,3R）-酒石酸-二-烷基酯涂敷薄层色谱拆分不能实现拆分.通过比较手性选择体结构,探讨了拆分机理.     

毛细管区带电泳对手性药物盐酸美西律和盐酸异博定的对映体分离

应用环糊精-毛细管区带电泳体系对手性药物盐酸美西律和盐酸异博定的对映体分离进行了研究。结果表明, 在所研究的手性选择剂α-环糊精, β-环糊精, 二甲基-β-环糊精, 羟丙基β-环糊精和γ-环糊精中, 羟丙基β-环糊精对所研究的手性药物分离效果较好。对盐酸美西律和盐酸异博定的最佳羟丙基-β-环糊精浓度分别为30mmol/L和9mmol/L, 最佳缓冲溶液浓度为100mmol/L Tris-H3PO4(pH2.3)。向缓冲溶液中加入0.05%羟丙基纤维素(HPLC)可改善分离。盐酸美西律获得了接近基线的手性分离, 而盐酸异博定亦获得了较好的分离。     

紫外分光光度法检测盐酸中的乙酸

用紫外分光光度法检测盐酸中的微量乙酸。确定了乙酸的最大吸光度和相关线性范围。检测了不同浓度的乙酸在 10 % (体积分数 )盐酸中的线性关系。认为在 10 %盐酸中 3 8g·L- 1的乙酸呈良好的线性关系。该方法简便、实用、快速。适用于氯乙酸合成生产线的盐酸检测。     

离子液体作为添加剂的毛细管电泳法拆分盐酸金刚乙胺

将新离子液体[EIMCH2CONHBu]BF4用于毛细管电泳法拆分手性药物,建立了以β-环糊精为手性选择剂拆分盐酸金刚乙胺对映体的毛细管电泳方法。分别考察了离子液体浓度,手性选择剂浓度,缓冲溶液种类、浓度及pH值,分离电压等参数对分离度的影响,从而确定了盐酸金刚乙胺对映体的最佳拆分条件:[EIMCH2CONHBu]BF4溶液体积分数3.2%,β-环糊精18 mmol/L,NaH2PO4 15 mmol/L,缓冲液pH 3.03,分离电压15 kV。在优化的实验条件下,盐酸金刚乙胺对映体得到基线分离,分离度可达1.51。实验结果表明[EIMCH2CONHBu]BF4能够增强β-环糊精的手性拆分能力,对手性拆分有协同作用。     

反相高效液相色谱法测定盐酸索他洛尔

 建立了用于盐酸索他洛尔的含量测定、有关物质的检查和稳定性考察的 RP-HPL C法。采用 ODS柱、体积分数为 0 .1 %的乙酸水溶液 -乙腈 (体积比为 80∶ 2 0 )为流动相的色谱条件 ,以磺胺二甲基嘧啶为内标物 ,测定的线性范围为 5～ 45 mg/ L(r=0 .9991 ) ,日内精密度为 0 .2 0 % ,日间精密度为 0 .93 %。     

反相高效液相色谱法测定盐酸索他洛尔

建立了用于盐酸索他洛尔的含量测定、有关物质的检查和稳定性考察的 RP-HPL C法。采用 ODS柱、体积分数为 0 .1 %的乙酸水溶液 -乙腈 (体积比为 80∶ 2 0 )为流动相的色谱条件 ,以磺胺二甲基嘧啶为内标物 ,测定的线性范围为 5～ 45 mg/ L(r=0 .9991 ) ,日内精密度为 0 .2 0 % ,日间精密度为 0 .93 %。     

微流控芯片非接触电导法快速测定盐酸美金刚片中盐酸美金刚的含量

建立了微流控芯片非接触电导法快速测定盐酸美金刚片中盐酸美金刚含量的方法。探讨了缓冲溶液的种类、浓度、pH值、进样时间及分离电压等因素对分离检测的影响。优化得到缓冲体系为含2%(体积分数)二甲基亚砜(DMSO)的3.0 mmol/L三乙胺-2.0 mmol/L磷酸缓冲溶液(pH 3.3),进样时间为10 s,分离电压为2.0 kV。优化条件下,盐酸美金刚的线性范围为10～2 000μg/mL(r~2=0.999 1);检出限为7μg/mL,定量下限为10μg/mL;精密度、稳定性、重复性实验的相对标准偏差(RSD)均小于2.0%;平均加标回收率为96.5%～99.2%;盐酸美金刚的检测时间小于18 s。该方法快速简便,适用于盐酸美金刚片中盐酸美金刚含量的测定。     

鼻可灵喷雾剂中地塞米松磷酸钠、氧氟沙星及盐酸麻黄碱含量的微乳液相色谱法测定

建立了复方鼻可灵喷雾剂中3 组分的微乳液相色谱(MELC)测定方法,并考察了其影响因素.以微乳(33 g/L SDS-1.2%(体积分数)正辛烷-9%(体积分数)正丁醇-0.5%(体积分数)三乙胺,磷酸调pH至3)为流动相,采用Hypersil BDS C18 5 μm(4.6 mm×150 mm)色谱柱,检测波长256 nm.实验发现,被测组分地塞米松磷酸钠、氧氟沙星及盐酸麻黄碱的线性范围和相关系数分别为0.01 ～0.04 g/L,r＝0.999 9;0.1 ～0.3 g/L,r＝0.999 9;0.2 ～0.6 g/L,r＝0.999 9.对应的平均回收率和RSD(n=5)分别为97%,2.55%;101%,0.45%;101%,0.54%(n=5).     

以卡那霉素为选择剂对盐酸地匹福林的毛细管电泳拆分

本研究以卡那霉素作为手性选择剂,采用毛细管电泳法对盐酸地匹福林对映体进行手性拆分,并对分离条件进行优化。考察了卡那霉素的浓度、缓冲溶液pH值、柱温及有机添加剂等因素对分离的影响。优化分离条件为:卡那霉素浓度0.6%;有机添加剂5%:乙腈-甲醇混合物(体积比9∶1);20mmol/L pH=2的磷酸盐缓冲溶液;进样:25psi×2s;分离电压+20kV;检测波长262nm;柱温25℃。在此优化分离条件下,盐酸地匹福林实现基线分离。该方法操作简便,可用于盐酸地匹福林对映体的分离。     

反相高效液相色谱法测定盐酸丁卡因药膜的有关物质及含量

建立了反相高效液相色谱-紫外检测器法检测盐酸丁卡因药膜4种有关物质以及含量的方法。采用Shimadzu C18(4.6×150 mm,5μm)色谱柱,甲醇溶液(含体积分数0.45%三乙胺和10 mmol/L庚烷磺酸钠,60∶40,V:V)为流动相,用H3PO4调节pH 3.0;盐酸丁卡因在0.10~40μg/L浓度范围内呈良好线性关系(r=0.9999);平均回收率(n=9)为97.3%,RSD为0.68%,盐酸丁卡因和4种有关物质的检出限分别为0.1,0.01,0.005,0.01和0.02 mg/L。     

De Novo Asymmetric Syntheses of d-, l- and 8-epi-Swainsonine

A highly enantioselective and stereocontrolled approach to d-, l- and 8-epi-d-swainsonine has been developed from achiral furan and γ-butyrolactone. A one-pot hydrogenolysis of both azide and benzyl ether followed by an intramolecular reductive amination has been employed as key step to establish the indolizidine ring system. The absolute stereochemistry was installed by the Noyori reduction and the relative stereochemistry by the use of several highly diastereoselective palladium-catalyzed glycosylation, Luche reduction, dihydroxylation, and palladium-catalyzed azide allylation reactions. This practical approach provide multigram quantities of indolizidine natural product d-swainsonine in 13 steps and 25% overall yield.     

Hydroboration of terpenes—VIII: Cyclic hydroboration of d-(+)-limonene. A stereoselective synthesis of d-(−)-(1R, 2R, 4R)-limonene-2,9-diol and d-(−)-(1R, 2R, 4R)-carvomenthol

d-(+)-Limonene can be converted into the corresponding bicyclic organoborinate intermediate, B-methoxy-4,8-dimethyl-2-borabicyclo[3.3.1]nonane, by cyclic hydroboration with borane in THF, followed by methanolysis, and distillation of the product. Alternatively, cyclic hydroboration of d-(+)-limonene with thexylborane provides the related bicyclic organoborane intermediate, B-thexyl-4,8-dimethyl-2-borabicyclo[3.3.1]nonane. Oxidation of the respective intermediates produces d-(?)-(1R, 2R, 4R)-limonene-2,9-diol. Protonation of the bicyclic thexyl intermediate, followed by oxidation, provides d-(?)-(1R, 2R, 4R)-carvomenthol. These results suggest that the cyclic hydroboration of dienes can provide a valuable means for controlling the exact site of hydroboration, leading to a stereoselective synthesis of alcohols.     

3d-4f单分子磁体*

单分子磁体是指那些在磁场下能够被磁化,当磁场去除后仍能保持磁性的单个分子。由于在信息处理和储存方面具有潜在的广泛应用前景,单分子磁体日益成为化学、材料科学和物理等学科的研究热点。近年来,同时含有镧系金属离子和过渡金属离子的3d-4f单分子磁体更是引起了很多研究者的兴趣。本文阐述了3d-4f单分子磁体的优势,总结了3d-4f单分子磁体的常见合成方法及其磁性,分析了影响3d-4f单分子磁体磁性的因素。     

Voltammetry of p-, d-, and f-Block Elements in Mineral–Organic Supporting Electrolytes

This paper is devoted to the voltammetry of p-, d-, and f-block elements in mineral–organic supporting electrolytes containing strongly solvating organic solvents. The electrochemical behavior of p-, d-, and f-block ions under the specified conditions is discussed. The principle of selectivity control over the voltammetric determination of these elements is formulated. New methodological approaches are proposed to improve the accuracy and enhance the selectivity of voltammetric determinations.     

Conformational analysis of tertiobutyl-4, d-4, thiacyclohexane:by proton nmr spectroscopy

Proton NMR studies of tertiobutyl-4, D-4, thiacyclohexane, which has a fixed chair conformation, have allowed a direct determination of the various coupling constants. A discussion of the values of the ring torsion angles calculated from the different gauche constants ³J shows that the most probable value is given by J_Hαe,H_βa for which there is no hydrogen atom antiperiplanar to the S atom.     

Furanoside diphosphines derived from d-(+)-xylose and d-(+)-glucose as ligands in rhodium-catalysed asymmetric hydroformylation reactions

Chirality transfer by furanoside diphosphines 1–3 was investigated in the Rh-catalysed asymmetric hydroformylation of prochiral olefins. In general, they induced high regioselectivities with branched aldehydes and moderate enantioselectivities of up to 58%. Improved activities were seen when a methyl substituent was introduced at C-(5) of the sugar residue. Systematic variation of the configuration at C-(5) suggests that there is a cooperative effect between stereocentres, which results in a matched combination for ligand 3 with (R)-configuration at the C-(5) stereogenic centre. Introduction of a methyl substituent at C-(5) induces a strong coordination preference. The solution structures of the species formed under hydroformylation conditions were also investigated.     

Three-dimensional 3d-4d Heterometallic Coordination Polymer——Synthesis,Structure,Magnetic and Luminescent Properties

A new three-dimensional 3d-4d heterometallic coordination polymer,[Cd2Mn(H2O)4(BTC)2]·2H2O(BTC=1,3,5-benzenetricarboxylate) was prepared under hydrothermal conditions and characterized by single crystal X-ray diffraction.This compound crystallized in the monoclinic space group C2/c,with cell parameters a=1.9452(4) nm,b=0.7094(2) nm,c=1.8064(4) nm,β=118.02(3)°,V=2.2004(8) nm3 and Z=4.Its structure contains trinuclear mixed metal clusters,which are further connected by BTC to form a three-dimensional framework.The compound exhibits intense photoluminescence at room temperature.Magnetic studies of the compound show a dominant antiferromagnetic exchange between the Mn(Ⅱ) ions.     

Diboriranide σ-Complexes of d- and p-Block Metals

Diboriranides are the smallest conceivable monoanionic aromatic cycles, yet only limited examples have been reported and their reactivity and complexation behavior remain completely unexplored. We report a straightforward synthesis of the first peraryl diboriranide c-(DurB)₂CPh⁻ as its lithium salt in three steps via the corresponding non-classical diborirane from a readily available 1,2-dichlorodiborane(4) (Dur=2,3,5,6-tetramethylphenyl). With the preparation and complete characterization of representative complexes with tin, copper, gold and zinc, we demonstrate the strong preference of the diboriranide for σ-type coordination modes towards main group and transition metal centers under unperturbed retention of the three-membered B₂C-ring's 2e⁻ π-system.