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Chiral Separations in Normal‐phase Liquid Chromatography: Updating a Screening Strategy with a Chlorine‐containing Polysaccharide‐based Selector 下载免费PDF全文
Jie Zhou Shanshan Chen Pei Luo Chong Sun Lingchang Meng Qiuzheng Du Fang Sun 《中国化学会会志》2015,62(12):1059-1067
The screening conditions of an existing column and mobile phase selection strategy for chiral compounds in normal‐phase high performance liquid chromatography (NP‐HPLC) were tested for their applicability on Chiralpak IC, which is a chiral stationary phase (CSP) made by immobilising cellulosic tris (3,5‐dichlorophenyl‐carbamate) on silica gel. In this study, the applicability of the optimization steps of the existing separation strategy was examined using 36 compounds representing the three possible resolution situations that occur after screening. The cumulative number of separated compounds is 27 (75.0 %), and the cumulative number of baseline separated compounds is 19 (52.8 %). 相似文献
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Chiral separability of boron cluster species studied by screening approaches utilizing polysaccharide‐based chiral stationary phases 下载免费PDF全文
In this study, the screening steps of chiral separation strategies with polysaccharide‐based chiral stationary phases were applied on boron cluster compounds in normal‐phase liquid chromatography (NPLC) and polar organic solvents chromatography (POSC). Since the screening steps were initially developed to analyze organic compounds, their applicability for boron clusters was investigated. Overall, the screening steps in NPLC were applicable for the separation of zwitterions, while for anions mostly no elution was observed. A hypothesis for the latter behavior is precipitation of anions in the nonpolar mobile phases. Ten out of 11 compounds could be partially or baseline separated on the NPLC screening systems. In POSC, all zwitterions were separated on at least one of the screening systems, with an overall lower retention as in NPLC. Anions were detected but not separated in the majority of the experiments. Also their retention on the chiral stationary phases was very limited. This study showed that the chiral discrimination potential of chemically modified polysaccharides is meaningful for chiral separations of structurally chiral boron cluster species, but needs further systematic research, in which recognition mechanisms should be further explored. In addition, some unusual peaks also indicated that conditions with a high separation efficiency must first be searched for some of the tested systems. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Chiral electromigration methods in food analysis 总被引:1,自引:0,他引:1
This review article addresses the different chiral capillary electrophoretic methods that are being used for the study and characterization of foods and food compounds (e.g., amino acids, organic acids, sugars, pesticides). An updated overview, including works published till December 2002, on the principal applications of enantioselective procedures together with their main advantages and drawbacks in food analysis is provided. Some anticipated applications of chiral electromigration methods in food characterization are also discussed. 相似文献
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采用高效液相色谱法,在自制的纤维素-三(3,5-二甲基苯基氨基甲酸酯)(ATEO-OD)、纤维素-三(4-甲基苯基氨基甲酸酯)(ATEO-OG)和纤维素-三(4-甲基苯基甲酸酯)(ATEO-OJ)3种手性柱上对16种不同结构的手性化合物进行了拆分和比较.试验结果表明:16个手性样品在这3种手性固定相上分别获得了不同程度的拆分,A TEO-OD对所分析样品具有更好的手性识别能力,ATEO-OG和ATEO-OJ的手性识别能力相当. 相似文献
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We report on the chiral separation of pharmacologically active dihydropyrimidinones by capillary electrophoresis (CE) using carboxymethyl-beta-cyclodextrin as chiral selector. The influence of selector concentration, pH, and the addition of varying amounts of methanol is investigated. Out of 21 compounds investigated, 19 were resolved, 13 with baseline separation. 相似文献
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A series of novel chiral triazole compounds were synthesized. They were separated into enantiomers by liquid chromatography on an amylose tris(3,5-dimethylphenylcarbamate) (ADMPC) chiral stationary phase (CSP). The absolute configuration of each enantiomer of the investigated compounds was established by combined use of chemical correlation, chiral HPLC and circular dichroism (CD) spectra analysis methods. The influence of the mobile-phase modifiers and the structure of chiral triazole compounds on the chiral separation and retention were investigated. Reversal of the elution order of some enantiomeric pairs upon using different mobile-phase modifier was observed. The temperature effect on the chiral separation and the thermodynamic properties including enthalpy and entropy change of binding to the ADMPC-CSP were also investigated. 相似文献
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Chiral separations of FITC-labeled basic drugs on multichannel microfluidic chips with LIF detector were investigated. A preliminary screening procedure for seven neutral CDs was performed under optimized conditions for chiral separations of three FITC-labeled drugs (baclofen, norfenefrine, and tocainide) on a mono-channel microfluidic chip. According to the results of screening, FITC-baclofen and FITC-norfenefrine as well as two chiral selectors including gamma-CD and dimethyl-beta-CD (DM-beta-CD) were selected as models to perform chiral separations on a two-channel chip. FITC-baclofen enantiomers were separated completely by gamma-CD in one channel, while resolution of FITC-norfenefrine enantiomers was achieved by DM-beta-CD in the other channel in the same run. Furthermore, the feasibility of using one chiral selector to separate multiple chiral samples was studied on a four-channel chip. These results show that multichannel chip has a potential for chiral high-throughput screening. 相似文献
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Lignans are dimeric phenylpropanoid compounds in plants that enjoy increasing medicinal interest because of their phytoestrogen activity. Lignans are chiral compounds and for most natural occurring lignans, chirality is not known. Separation of racemic matairesinol by CE in a non-coated silica capillary with carboxymethyl-beta-cyclodextrin as chiral selector in phosphate buffer was successful. Electrolyte and selector concentrations and pH were systematically optimized in order to obtain baseline separation and short analysis times. Matairesinol from safflower fruit was determined as (-)-enantiomer. Quantitation results for matairesinol with the optimized method after calibration with authentic lignan were very similar to those by HPLC. The limit of detection is 2 microg/mL sample by DAD detection. 相似文献
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Hernández-Borges J Rodríguez-Delgado MA García-Montelongo FJ Cifuentes A 《Electrophoresis》2005,26(20):3799-3813
Chiral separation of enantiomers is one of the most challenging tasks for any analytical technique including CE. Since the first report in 1985 showing the great possibilities of CE for the separation of chiral compounds, the amount of publications concerning this topic has quickly increased. Although chiral electromigration methods have mainly been used for enantioseparation of drugs and pharmaceuticals, they have also been applied to analyze chiral pollutants. This article intends to provide an updated overview, including works published till January 2005, on the principal applications of CE to the chiral analysis of pollutants and their metabolites, with special emphasis on articles published in the last 10 years. The main advantages and drawbacks regarding the use of CE for chiral separation of pollutants are addressed including some discussion on the foreseen trends of electromigration procedures applied to chiral analysis of contaminants. 相似文献
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Novel chiral compounds have been synthesized for the enantioselective fluorescent recognition of alpha-hydroxycarboxylic acids and amino acids. By introducing dendritic branches to the chiral receptor units, the fluorescence signals of the receptors are significantly amplified because of the light-harvesting effect of the dendritic structure. This has greatly increased the sensitivity of the sensors in the fluorescent recognition. Highly enantioselective fluorescent responses have also been ac… 相似文献
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Dr. Andrey E. Sheshenev Dr. Ekaterina V. Boltukhina Anastasiya A. Grishina Dr. Ivana Cisa?ova Dr. Ilya M. Lyapkalo Dr. King Kuok Hii 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(25):8136-8143
A family of new chiral zwitterionic phosphorus‐containing heterocycles (zPHC) have been derived from methylene‐bridged bis(imidazolines). These structures were unambiguously determined, including single‐crystal XRD analysis for two compounds. The stability, acid/base and electronic properties of these dipolar phosphorus heterocycles were subsequently investigated. zPHCs can be successfully employed as a new class of chiral solvating agents for the enantiodifferentiation of chiral carboxylic and sulfonic acids by NMR spectroscopy. The stoichiometry and binding constants for the donor–acceptor complexes formed were established by NMR titration methods. 相似文献
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手性杯芳烃是一类重要的主体化合物,在手性识别、对映体分离和不对称催化等方面有着广泛的用途。[4]芳烃引其稳定的构象和易于修饰的特点,成为研究最为广泛的杯芳烃分子,其中大量的文献报道了能够用于对映体识别和检测的手性[4]芳烃。在手性识别的研究中,荧光、紫外和核磁是3中最常见的研究方法,本文根据这3种方法进行分类,综述了近年来以杯[4]芳烃为分子骨架的手性受体的合成及其在手性识别中的应用。最后对手性[4]芳烃的发展前景作了展望。 相似文献
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Numerous chemical compounds of high practical importance, such as drugs, fertilizers, and food additives are being commercialized as racemic mixtures, although in most cases only one of the isomers possesses the desirable properties. As our understanding of the biological actions of chiral compounds has improved, the investigation of the pharmacological and toxicological properties has become more and more important. Chirality has become a major issue in the pharmaceutical industry; therefore, there is a continuous demand to extend the available analytical methods for enantiomeric separations and enhance their efficiency. Direct liquid chromatography methods based on the application of chiral stationary phases have become a very sophisticated field of enantiomeric separations by now. Hundreds of chiral stationary phases have been commercialized so far. Among these, macrocyclic glycopeptide-based chiral selectors have proved to be an exceptionally useful class of chiral selectors for the separation of enantiomers of biological and pharmacological importance. This review focuses on direct liquid chromatography-based enantiomer separations, applying macrocyclic glycopeptide-based chiral selectors. Special attention is paid to the characterization of the physico-chemical properties of these macrocyclic glycopeptide antibiotics providing detailed information on their applications published recently. 相似文献
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Chiral Method Development Strategies for HPLC using Macrocyclic Glycopeptide-Based Stationary Phases
Chiral HPLC methods using macrocyclic glycopeptide-based chiral stationary phases have been widely used and reported; however, the development of efficient methods to separate and quantify the analytes with high resolution is a challenging task. Therefore, the knowledge regarding the optimization of chromatographic parameters regarding this type of chiral chromatography is essential. This review presents and discusses the optimization of HPLC conditions and parameters for the chiral resolution of racemic drugs on macrocyclic glycopeptide-based chiral stationary phases. Strategies for chiral method development are presented, using polar ionic, reversed phase, normal phase and polar organic modes. The effect of the most important chromatographic parameters, such as mobile phase composition, flow rate and temperature on the enantioseparation are discussed aiming the adequate screening and optimization protocol for each mode. 相似文献
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对映体脂肪胺在有机合成与化工领域具有广泛的应用, 但其主要依赖于金属催化获得. 我们设计了一种光催化与酶催化级联催化的合成方法, 由脂肪醇出发合成手性脂肪胺. 通过筛选, 发现9-芴酮在可见光激发下可高效催化脂肪醇氧化为脂肪酮, 后者作为反应中间体被转氨酶在胺供体存在下经转氨反应合成手性胺. 在一锅法条件下, 该级联方法转化率可达99%, 目标产物的光学纯度>99%. 此外, 该光催化体系可分别与手性互补的转氨酶级联, 进而获得手性反转的脂肪胺产物. 该光酶级联催化方法充分结合了光催化的高效率与酶催化的立体选择性优势, 为手性脂肪胺类分子的合成提供了一种新型合成方法. 相似文献