Investigation of Mixed Chiral Selectors of Different Metal Ion-L-Alanine Complex and β-Cyclodextrin on the Chiral Separation of Dansyl Amino Acids with Capillary Electrophoresis

Chiral separation of dausyl amino acids by capillary electrophoresis using mixed selectors of Mn(ll)-L-alanine complex and β-cyclodextrin (β-CD) was studied. Resolution was considerably superior to that obtained by using either Mn (Ⅱ)-L-alanine complex or β-CD alone. The effects of separation parameters, such as pH value of buffer solution, capillary temperature, the concentration of Mn (Ⅱ)-L-alanine complex, the types of CD and ligand on the migration times and resolutions were investigated. Six different transition metal complexes,Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Hg(Ⅱ) and Cd(Ⅱ)-L-alanine complexes have been employed and compared with Mn(Ⅱ)complex. Differences in retention and selectivity were found.The substitution of Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) for Mn(Ⅱ) resulted in a better chiral resolution while Hg(Ⅱ) and Cd(Ⅱ) showed poorer resolution abilities. The chiral separation mechanism was also discussed briefly.     

3-位烯丙基及甲基衍生的β-环糊精固定相的合成及气相色谱性能研究

制备了一种新的β-环糊精衍生物固定相2,6-二-O-戊基-3-O-[(甲基)5(烯丙基)2]-β-CD,并对其气相色谱分离性能进行研究。实验显示,该固定相具有良好的柱表面性能和较强的色谱分离能力,对一些芳香族位置异构体的分离能力优于2,6-二-O-戊基-3-O-烯丙基-β-CD衍生物,对10余种手性物质显示出较好的选择性能,且对α-位取代的丙酸酯类手性分离效果明显优于杂环类β-CD衍生物。与2,6-二-O-戊基-3-O-烯丙基-β-CD固定相的分离性能比较表明,β-CD 3位羟基部分甲基基团的引入能增强对芳香族位置异构体的选择能力,但不能明显改变烯丙基衍生物的手性分离能力。     

新型三唑氮杂环β-环糊精固定相的制备及其气相色谱性能研究

制备了一种新的含氮三唑类β-环糊精固定相2,6-二-O-戊基-3-O-亚甲基-[1-(1,2,4)-三唑基]-β-环糊精,对其气相色谱分离性能进行了研究.实验结果表明,固定相具有较强的色谱分离能力,氯甲苯、二氯苯等难分离的芳香族位置异构体和含两个手性中心的拟除虫菊酯对映异构体均得到了很好的分离.该固定相是一种有应用前景的气相色谱固定相.     

一种五元杂环β-环糊精固定相的合成及气相色谱性能研究

制备了一种新的含多氮五元杂环类β-环糊精固定相2,6-二-O-甲基-3-O-亚甲基-[1-(1,2,4)-三唑基]-β-环糊精,对其气相色谱分离性能进行了研究.实验结果表明,杂环官能团的引入较大提高了该固定相的柱表面性能和色谱分离能力.不但对二甲苯、硝甲苯等难分离的芳香族位置异构体,而且对醇、胺、酯等多种类型的手性异构体均有很好的分离能力和手性选择能力.     

Gas Chromatographic Enantiomer Separation of Cyclopropane Derivatives on Three 2, 6-Di-O-allyl-3-O-acylated-β-cyclodextrins Chiral Stationary Phases

Eight pairs of enantiomers of cyclopropane derivatives were resolved on capillary gaschromatographic columns using three new 2, 6-di-O-allyl-3-O-acylated-β-cyclodextrins as chiralstationary phases. It was found that the three β-CDs can separate some of the racemic cyclopropanederivatives well.     

Synthesis and Chromatographic Properties of New β-Cyclodextrin Derivatives with α-Schiff Base Groups for HPLC

β-Cyclodextrin 1 was directly oxidized to the corresponding monoaldehyde 2 on their primary faces by cyclized 2-iodoxybenzoic acid(IBX) in DMSO, followed by the synthesis of β-cyclodextrin derivatives bearing Schiff-base group 3. A new chiral stationary phase(BCDS 6) was then prepared by immobilization of β-cyclodextrin derivative with α-Schiff base group onto the surface of sillica gel. A series of compounds with amino groups were readily separated using this CSE Methanol and acetonitrile were tested as the mobile phase while the influence of temperature and the addition of aqueous triethylammonium acetate buffer to the mobile phase was also innvestigated. Ferrocene ligand with Schiff-based groups have been separated satisfactorilly on BCDS column.     

Study on the Supramolecular Interaction of β-Cyclodextrin with Gemfibrozil by Spectrofluorimetry and Its Analytical Application

The supramolecular interaction of gemfibrozil with β-cyclodextrin （β-CD） was studied by spectrofluorimetry. The mechanism of the inclusion was discussed by spectrofluoremetry, infrared spectrum and ^1H NMR spectrum. The results showed that a 1 ： 1 （β-CD ： gemfibrozil） complex was formed with an apparent association constant of 3.844 × 10^3 L·mol^-1. Based on the enhancement of the fluorescent intensity of gemfibrozil, a spectrofluorimetric method for the determination of gemfibrozil in bulk aqueous solution in the presence of β-CD was developed. The linear range was 3.30 ng·mL^- 1 -6.00 ug·mL^-1 with the detection limit of 0.980 ng·mL^-1. There was no interference from the excipients normally used in tablet composition and the serum main compositions. The proposed method was then successfully applied to the determination of gemfibrozil in capsules and serum.     

Synthesis and Properties of Novel Hemicyanine Dye-β-Cyclodextrin

A series of novel hemicyanine dye-β-cyclodextrin compounds： mono-6-deoxy-β-cyclodextrin-6-[p-（p-substituted styryl）pyridium] p-totylfulfonates were synthesized by the condensation of mono-6-deoxy-β- cyclodextrin-6-（p-methyl pyridinium） p-toluenesulfonate with （un）substituted benzaldehydes. Their structures were established by 1^H NMR, IR, UV-Vis and elemental analysis. The absorption and fluorescence properties of the novel compounds were measured in solution and the photostability of a selected hemicyanine dye-β-cyclodextrin compound was also investigated.     

Carboxymethyl-β-cyclodextrin for Chiral Separation of Amino Acids Derivatized with Fluorescene-5-isothiocyanate by Capillary Electrophoresis and Laser-induced Fluorescence Detection

A method using carboxymethyl-β-cyclodextrin (CM-β-CD) as selector for chiral separation of amino acids by capillary electrophoresis and laser-induced fluorescence detection was studied. Resolution was better than that obtained by β-CD or HP-β-CD.     

Determination Enantiomer Excess （e.e. %） of Chiral Sharpless Epoxides with [~-Cyclodextrin Derivatives as Chiral Stationary Phases of Capillary Gas Chromatography

Using four β-cyclodextrin derivatives, 2,6-di-O-benzyl-3-O-heptanonyl-β-CD, 2,6-di- O-benzyl-3-O-octanonyl-β-CD, 2,3-di-O-benzyl-6-O-heptanonyl-β-CD, and 2,3-di-O-benzyl -6-O- octanonyl-β-CD, as chiral stationary phases of capillary gas chromatography （CGC）, the enantiomers of Sharpless epoxides were well separated. The enantiomer excess values （e.e.%） of some chiral Sharpless epoxides were also determined successfully using these CDs.     

一种新型接枝聚硅氧烷环糊精衍生物的合成及其气相色谱性能的研究

合成了一种新的环糊精接枝聚硅氧烷固定相(DPP-β-CD),并将其成功涂渍到气相色谱毛细管柱上．发现其涂渍性能良好：对二甲苯、氯苯胺等难分离的芳香族位置异构体和一些对映异构体具有好的分离能力,是一种有应用前景的气相色谱固定相。     

Enantiomeric Separation of Epinephrine and Salbutamol by Micellar Electrokinetic Chromatography Using β-Cyclodextrin as Chiral Additive

Introduction The development of chiral substances, especially inthe pharmaceutical field, places increasing demands onanalytical methods for the separation of these kinds ofisomers and the chiral purity control of drugs in phar-macokinetic studies. As the enantiomers of epinephrineand salbutamol have different pharmacological andtoxicological characteristics, separation and quantitationof the single enantiomers are required. Analytical methods used so far for the enantiomerseparation inclu…     

一种新的β-环糊精衍生物手性固定相的制备及其气相色谱性能

合成了一种新的手性固定相2，6－O－二丁基－3－O－三甲基硅烷基－β－环糊精，以甲基苯基硅油为稀释剂，采用快速超动态法，成功地将其涂渍到弹性石英毛细管柱上；柱性能稳定，柱寿命较长；用该柱分离了酯、酮、烯烃等一些对映体。     

Enantiomeric Separation of Epinephrine and Salbutamol by Micellar Electrokinetic Chromatography Using β-Cyclodextrin as Chiral Additive

Enantiomeric separation of epinephrine and salbutamol was investigated by micellar electrokinetic chromatography employing β-cyclodextrin as chiral additive in ammonium chloride-ammonia solution. The analytes were detected by electrochemistry using gold microelectrode at 0.65 V versus SCE reference electrode. The effects of detection potential,concentration of β-cyclodextrin, concentration of sodium dodecyl sulfate, pH value of electrolyte and applied voltage were discussed.     

2，6-二-O-乙氧乙基-3-O-三氟乙酰基-β-环糊精气相色谱手性固定相的制备及应用

将β-环糊精的2,6-位引入乙氧乙基,3-位引入三氟乙酰基,合成了新的环糊精衍生物2,6-二-O-乙氧乙基-3-O-三氟乙酰基-β-环糊精,并采用静态法涂渍毛细管气相色谱柱,考察了毛细管柱的柱性能和分离性能。结果表明,该固定相对G rob试剂、苯的二取代位置异构体氯甲苯、硝基甲苯和溴甲苯以及10种手性化合物如α-取代丙酸酯化合物、1-(2′-硝基苯基)-乙醇、α-甲基-对氯苯乙腈和丙炔醇酮乙酸酯等具有良好的分离效果。其中,对α-甲磺酰基丙酸酯对映体的拆分效果最好;对α-取代丙酸的甲酯衍生物的分离效果优于乙酯衍生物;对α-羟基取代丙酸酯的分离效果优于α-卤代丙酸酯。     

手性色谱固定相——全甲基化2,3,6-三(O-2′-混旋羟丙基)-β-环糊精的立体选择性研究

合成了一种新的手性色谱固定相——全甲基化２，３，６－三（Ｏ－２′－混旋羟丙基）－β－环糊精（ＰＭＲＨＰ－β－ＣＤ），以静态法将其涂于０．２５ｍｍ×１６０００ｍｍ弹性石英毛细管柱上，以醇、氨基酸、酯、卤代烃等手性化合物考察了新固定相对对映异构体的拆分能力。结果表明，新的固定相具有较高的立体选择性。     

2,3-二-O-甲氧乙基-6-O-苄基-β-环糊精的合成及其气相色谱性能

将β-环糊精的2,3位引入甲氧乙基,6位引入苄基,合成新的环糊精衍生物2,3-二-O-甲氧乙基-6-O-苄基-β-环糊精,并采用静态法涂渍5g·L~(-1)新环糊精制备石英毛细管色谱柱,考察了毛细管柱的柱性能和分离性能。结果表明:该固定相对Grob试剂、苯的二取代位置异构体二氯苯、硝基甲苯和溴甲苯以及手性化合物α-乙基-2-甲氧基苯甲醇、α-乙基-3-甲氧基苯甲醇、α-甲基-对氯苯乙腈、α-苄基-对氯苯乙腈、1-(2′,4′-二氯苯氧基)-2-丙醇和2-溴丙酸甲酯都具有良好的分离效果。     

手性色谱固定相——全甲基化2,3,6-三(O-2′-混旋羟丙基)-β-环糊精的立体选择性研究

 合成了一种新的手性色谱固定相——全甲基化２，３，６－三（Ｏ－２′－混旋羟丙基）－β－环糊精（ＰＭＲＨＰ－β－ＣＤ），以静态法将其涂于０．２５ｍｍ×１６０００ｍｍ弹性石英毛细管柱上，以醇、氨基酸、酯、卤代烃等手性化合物考察了新固定相对对映异构体的拆分能力。结果表明，新的固定相具有较高的立体选择性。     

全戊基部分羟丙基β-环糊精手性固定相的制备与研究

以β-环糊精为母体,制备了一种新型固定相,全戊基2,3,6-三(O-2’羟丙基)-β-CD,研究了该固定相的有关色谱性能,结果表明对许多异构体,特别是对对映异构体具有较好的分离效果。     

β—环糊精衍生物手性固定相的研究及应用

合成了一种新的手性固定相２,６-Ｏ-二庚基-３-Ｏ三甲基硅烷基-β环糊精，以甲基苯硅油为稀释剂，采用快速超动态法，成功地制备了高效手性毛细管柱，考察了手性柱的色谱性能，分离了醇、酮、烯烃类等一些对映体。