| The chiral character of compound is very prevalence, which is arisen abroad attention in medicament, pesticide and life chemistry. In view of the special relation of organic molecule's three-dimensional structure to its biological activity, it is significant to form enantiomers separating and measuring method of high specialization and high degree of resolution for boosting molecular activity and lessening side effect and researching mechanism of action in depth. Scientists focus on chromatography gradually in virtue of its strong applicability, wide application prospects and high degree of purity.At present high performance liquid chromatography (HPLC), gas chromatography (GC), thin-layer chromatography (TLC), supercritical fluid chromatography (SFC), and capillary electrophoresis (CE) are in common use of chiral separation. Of which, HPLC and GC are successfully used for separation and preparation of many enantiomers. To find chiral stationary phase (CSP) with asymmetrical center and ability to chiral recognition is the advancing front of chiral chromatography, as well as its core and crux. There were more than 700 CSP having been studied, and some of them have been commodity column. The (-CD CSPs are of most use.Gas Chromatographic capillary columns with CD and its derivatives as stationary phases are prepared by using CD and its derivatives dissolved in polysiloxanes of middle polarity (e.g.OV-1701) because they are difficult to be used as GC stationary phase coatings. However, another approach is often selected, which is to prepare CD derivatives with lower melting points and different properties to be coated on capillary columns without using diluents. Cyclodextrin-based GC columns were found to have widespread utilize for the direct resolution of enantiomers, with numerous of novel phases continuing to be developed. New CSPs based on long-chain alkylated (-CD or containing other group were synthesized, and the enantiomeric separation of amines, alcohols, diols, carboxylic acids, amino acids, epoxides, halohydrocarbons, and ketones was evaluated. It was found that modifying the substitution pattern of the derivative groups in position 2 and 3 and 6 or changing from α-, (- or γ-CD significantly affected the separation properties of the CD derivatives.In this paper, three novel CSPs based on (-CD derivatives are prepared and studied. We synthesized bis(6-O-butene diacid ester)-(- cyclodextrin. The cavum,figure and polarity of the matrix was changed after it modified by C = C double bonds. The derivative was coated on 101 supporter washed by HCl as chiral stationary phase. By this method we prepared the gas chromatographic stationary phase for packed column. An another new gas chromatographic stationary phase called perpentyl(2,3,6-tri-(O-2'-hydroxypropyl)- (-CD also has been synthesized based on (-CD. Then it was coated on Chromosorb W AW. This CSP is modified by polar hydroxypropyl and long-chain perpentyl, which will influence on its polarity and hydrophilicity. Compared with general persubstituted CDs, it has racemic hydroxypropyl to increase its unsymmetry, which will strengthen enatioselectivity. The chromato- graphic property of the two stationary phases was studied by investigating the retention behavior and separations of a series of compounds. We found that the two derivatives have good separations to compounds, especially to some enantiomers we expect. A water-soluble (-CD polymer cross-linked with epoxy chloropropane has been synthesized. After benyslating, the derivative was coated on silica capillary column by dynamic method. The chromatographic properties and retention behaviors of the fused silica capillary columns were studied. The results showed that the novel CSP had good stereoselectivity and separation to some isomers. When we had (-CD derivative which is benyslating directly use as stationary phase, the column efficiency and stereoselectivity descended markedly. Compared with the two CSPs, the retention mechanism of separation was discussed abecedarianly.It sho... |
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