共查询到20条相似文献,搜索用时 125 毫秒
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1引言环糊精及其电中性衍生物(二甲基-β-环糊精(DM-β-CD)、三甲基-β-环糊精(TM-β-CD)、羟丙基-β-环糊精(HP-β-CD))是毛细管电泳(HPCE)手性分离中最常采用的手性选择剂,带电环糊精是HPCE手性分离中另一类重要的手性选择剂,它的带电性质使其在手性拆分过程中起到非常重要的作用。本文分别考察了带电的磺丁基-β-环糊精(SBB-β-CD)与电中性的DM-β-CD、TM-β-CD以及HP-β-CD等3种双环糊精体系的手性拆分性能,研究了双环糊精在手性分离中所体现出的协同效应… 相似文献
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体异构体和光学异构体分离技术的发展已有较综合的论述l‘”‘]。利用TLC对光学异构体进行拆分的方法主要有两种。1)使用手性同定相l’,‘];2)利用手性流动相在非手性固定相上进行拆分r‘。本文对立体异构体的分离采用一般的TLC法,对对映异构体的分离选用p-CD手性流动相,*一奎宁手性流动相和手性固定相纤维素板及非手性C;s反相板对三哇及氨基酸进行了拆分,并初步探讨了方形板及楔形板展开对分离效果的影响。1实验部分1.1试剂及材料二哩类化合物及标样均为自制,标样均通过元素分析;D,L一色氨酸,D一色… 相似文献
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在ChiralcelOD,ChiralcelOJ及ChiralpakAD等3种多糖类手性固定相上,以各种配比的正己烷-异丙醇为洗脱剂,对7种异口恶唑啉及异口恶唑烷类化合物的对映体进行了手性拆分。考察了这些外消旋物在这些手性柱上的色谱行为。实验结果表明,手性固定相上葡萄糖片段构型的差异和它们高级结构的不同以及手性固定相上的二甲基苯基氨基甲酸酯或对甲基苯甲酸酯等功能团与样品的极性基团之间的相互作用,可能是支配手性拆分的主要原因。方法已用于不对称1,3-偶极环加成反应产物的光学纯度鉴定。 相似文献
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羧甲基—β—环糊精用于毛细管电泳中的手性分离 总被引:4,自引:0,他引:4
本文将水溶性良好的羧甲基-β-CD(CM-β-CD_用于分离氯霉素中间体,考察了CM-β-CD作为毛细管电泳手性选择剂的分离性能。 相似文献
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在以正己烷-异丙醇为移动相的体系中,用ChiralcelOD,ChiralcelOJ及ChiralpakAD作为手性固定相对13种β-氨基醇及β-羟基硫醚类化合物对映体进行HPLC手性拆分,这些化合物至少能在一支柱上得到基线级分离。考察了它们于不同浓度配比的这类洗脱体系中在柱上的色谱行为。实验表明化合物取代基的性质明显影响它们在手性柱上的拆分。手性固定相与外消旋样品上的极性基团之间的氢键作用和π-π作用可能是进行手性识别的主要原因。方法已用于非手性环氧化合物不对称开环反应产物β-氨基醇及β-羟基硫醚类化合物的光学纯度鉴定。 相似文献
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The direct high-performance liquid chromatographic separation of three pairs of structurally related enantiomers on derivatized cellulose and amylose chiral stationary phases (Chiralcel OD, Chiralpak AD and Chiralpak AS) was studied using hexane as the mobile phase with 2-propanol or ethanol as modifiers. The separation, retention and elution order of the enantiomers on the different columns using different alcohol modifiers were compared. The effect of structural variation of the solutes on their k' was noted. A reversal of elution order of one enantiomeric pair upon changing the mobile-phase modifier was observed. Chiralcel OD and Chiralpak AD columns provided different elution orders of the enantiomers, including a fourth pair of enantiomers that were not structurally related to the other three pairs. 相似文献
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在ChiralcelOD,ChiralcelOJ及ChiralpakAD等3种多糖类手性固定相上,以各种配比的正己烷-异丙醇为洗脱剂,对7种异口恶唑啉及异口恶唑烷类化合物的对映体进行了手性拆分。考察了这些外消旋物在这些手性柱上的色谱行为。实验结果表明,手性固定相上葡萄糖片段构型的差异和它们高级结构的不同以及手性固定相上的二甲基苯基氨基甲酸酯或对甲基苯甲酸酯等功能团与样品的极性基团之间的相互作用,可能是支配手性拆分的主要原因。方法已用于不对称1,3-偶极环加成反应产物的光学纯度鉴定。 相似文献
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Luca Piemontese Salvatore Faliti Giuseppe Carbonara Antonio Laghezza Paolo Tortorella Fulvio Loiodice 《Chromatographia》2009,70(9-10):1327-1333
The LC enantiomeric separation of several dual PPARα/γ agonists on the commercially available Chiralcel OD and Chiralpak AD columns has been evaluated in normal phase mode using a mobile phase consisting in a mixture of n-hexane, 2-propanol and trifluoroacetic acid at constant volume ratio. Most compounds were separated as underivatized acids without requiring time consuming analysis. Some complementary selectivity was evidenced on the two investigated chiral stationary phases related to the different accessibility of the active sites of the helical cavities. Additional information on the chiral recognition mechanism were deduced from the chromatographic behaviour of some selected methyl esters. 相似文献
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Summary Analytical HPLC methods using derivatized cellulose chiral stationary phases have been developed for separation of the enantiomers
of 25 racemic 4-aryl-7,7-dimethyl- or 1,77-trimethyl-1,2,3,4,5,6,7,8-octahydroquinazoline-2,5-diones, condensed derivatives
of dihydropyrimidines. The enantiomers of the compounds were resolved by normal-phase chromatography on silica-based cellulose
tris(3,5-dimethylphenylcarbamate) (Chiralcel OD) and amylose tris(3,5-dimethylphenylcarbamate) (Chiralpak AD) columns with
mobile phases consisting of mixtures ofn-hexane and an alcohol (2-propanol, ethanol, or methanol) in different proportions. The mobile phase and the chiral stationary
phase were varied to achieve the best resolution. The effect of the concentration of alcohol in the mobile phase was studied.
The resolution obtained on the two columns was complementary. 相似文献
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Karin Balmr Bengt-Arne Persson Per-Olof Lagerstrm 《Journal of chromatography. A》1994,660(1-2):269-273
The enantioselective separation of omeprazole on different chiral stationary phases was investigated. The two enantiomers could be resolved on three different phases with immobilized protein, Chiral-AGP, Ultron ES-OVM and BSA-DSC, employing aqueous mobile phases with 2-propanol as organic modifier. On Chiralpak AD, an amylose-based chiral stationary phase, the enantiomers of omeprazole and three analogues could be separated using a non-polar hexane-ethanol mobile phase. For omeprazole the retention order was reversed when 2-propanol was replaced with ethanol or methanol as the modifier of hexane in the mobile phase. 相似文献
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F. La Torre R. Cirilli R. Costi R. Di Santo R. Ferretti B. Gallinella A. Salerno L. Zanitti 《Chromatographia》2004,60(3-4):171-178
The polysaccharide chiral stationary phases (CSPs) Chiralcel OD and Chiralpak AD, and the brush-type (R,R)-Whelk-01 chiral stationary phases have been evaluated to separate new synthetic pyrrolylphenylethanoneamine racemic compounds, potentially monoamine oxidase (MAO) inhibitors, under various mobile phase compositions, using various temperatures. The enantioseparation was evaluated by comparing the (R,R)-Whelk-01 column performance with those of Chiralpak AD and Chiralcel OD. Significant differences were observed in their chiral recognition, as revealed from their retention, selectivity, resolution and elution order. Performances of the Chiralpak AD column were superior to those of the Chiralcel OD and (R,R)-Whelk-01 columns. Some of the racemic compounds were resolved by semipreparative chromatography on Chiralpak AD column in order to study the chiroptical proprieties of the single enantiomers. 相似文献
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Mohammadhassan Foroughbakhshfasaei Mt Dob Francisc Boda Zoltn-Istvn Szab Gerg Tth 《Molecules (Basel, Switzerland)》2022,27(1)
The enantioseparation of four phthalimide derivatives (thalidomide, pomalidomide, lenalidomide and apremilast) was investigated on five different polysaccharide-type stationary phases (Chiralpak AD, Chiralpak AS, Lux Amylose-2, Chiralcel OD and Chiralcel OJ-H) using neat methanol (MeOH), ethanol (EtOH), 1-propanol (PROP), 2-propanol (IPA) and acetonitrile (ACN) as polar organic mobile phases and also in combination. Along with the separation capacity of the applied systems, our study also focuses on the elution sequences, the effect of mobile phase mixtures and the hysteresis of retention and selectivity. Although on several cases extremely high resolutions (Rs > 10) were observed for certain compounds, among the tested conditions only Chiralcel OJ-H column with MeOH was successful for baseline-separation of all investigated drugs. Chiral selector- and mobile-phase-dependent reversals of elution order were observed. Reversal of elution order and hysteresis of retention and enantioselectivity were further investigated using different eluent mixtures on Chiralpak AD, Chiralcel OD and Lux Amylose-2 column. In an IPA/MeOH mixture, enantiomer elution-order reversal was observed depending on the eluent composition. Furthermore, in eluent mixtures, enantioselectivity depends on the direction from which the composition of the eluent is approached, regardless of the eluent pair used on amylose-based columns. Using a mixture of polar alcohols not only the selectivities but the enantiomer elution order can also be fine-tuned on Chiralpak AD column, which opens up the possibility of a new type of chiral screening strategy. 相似文献