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Enantiomers of various chiral five- and six-membered-ring lactones, Which are important classes of compounds (flavour and Pheromone components, key intermediates in the synthesis of biologically active substances) have been separated chromatographically on the chiral phase cellulose triacetate, crystallographic form I (CTAI). For different series of five-membered-ring lactones, relationships have been found between the elution order of the enantiomers and their absolute configuration. Preparative resolutions of γ-Phenyl-γ-butyrolactone ( 1 ) and of the Pheromone component 5b have been carried out to demonstrate the applicability of the method to g-scale separations. 相似文献
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Francotte ER 《Journal of chromatography. A》2001,906(1-2):379-397
The preparative separation of enantiomers by chromatography on chiral stationary phases (CSPs) has been recognized as being a useful alternative to the more conventional approaches such as enantioselective synthesis and enzymatically catalyzed transformations. The possible contribution of enantioselective chromatography with respect to the preparation of enantiomerically pure compounds is reviewed in the context of the competitive approaches and depending on the application scale, with a special emphasis on the recent progresses achieved in this particular field of separation. 相似文献
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Separation of enantiomers by packed capillary electrochromatography on a cellulose-based stationary phase 总被引:1,自引:0,他引:1
Separation of enantiomers was performed by applying packed capillary electrochromatography (CEC). Fused-silica capillaries of different lengths with an inner diameter of 100 microm were packed with a cellulose derivative immobilized onto macroporous silica gel. Parameters such as content of modifier in the mobile phase, concentration and pH of the buffer were varied for a set of test capillaries to determine their influence on enantioselectivity. In packed CEC the highest influence on resolution of the test racemates was found by changing the acetonitrile content, while variation of the buffer concentration mostly affects the electroosmotic velocity. The performance of packed CEC and nano-LC was also compared. Packed CEC showed much better column efficiency and enantioselectivity under similar flow/electroosmotic velocity. 相似文献
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An enantioselective liquid chromatographic assay for the simultaneous determination of the S-(+) and R-(-) enantiomers of the monohydroxylated metabolite of oxcarbazepine in human plasma is described. The metabolite is the active principle. The method is based on the extraction of plasma with diethyl ether-dichloromethane (2:1, v/v), separation of the organic phase, evaporation of the solvent and dissolution of the residue in the mobile phase. The two enantiomers were resolved on a Chiralcel OD (250 mm x 4.6 mm I.D.) high-performance liquid chromatographic column. The separation was achieved by isocratic elution with n-hexane-2-propanol (77:23, v/v). The flow-rate of the mobile phase was 1.0 ml/min and the two enantiomers were detected by ultraviolet absorbance at 210 nm. The analytical method is suitable for the quantitative and simultaneous determination of the two enantiomers in plasma at concentrations down to 0.4 mumol/l after administration of oxcarbazepine. 相似文献
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Fritz Vgtle Annette Hünten Erik Vogel Sven Buschbeck Oliver Safarowsky Janosch Recker Amir‐Hossain Parham Michael Knott Walter M. Müller Ute Müller Yoshio Okamoto Takateru Kubota Wolfgang Lindner Eric Francotte Stefan Grimme 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2001,113(13):2534-2537
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An automated chiral separation-screening platform was developed, allowing separation analysis on one column while another column is simultaneously equilibrated with a different mobile phase (MP). The platform can be set up from usual HPLC components at moderate cost and it considerably speeds up the screening process, allowing numerous chromatographic conditions to be tested within a short period of time and leading to a significant gain in time and productivity in preparative separations. 相似文献
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