以羧甲基-β-环糊精为手性固定相填料,建立了反相高效液相色谱拆分17种顺式-β-内酰胺的方法.考察了流动相pH值、盐种类和浓度及流动相组成对分离效果的影响.选定的流动相为(0.10%NH4Ac+FA)(pH=5.0)-MeOH(体积比70:30),在此条件下,17个 β-内酰胺化合物中有7个化合物的分离度>1.5,4个化合物的分离度在1.0~1.5之间,其余化合物的分离度<1.0.理论拆分机理研究结果表明,羧甲基-β-环糊精手性拆分过程是环糊精的包结作用与氢键、偶极相互作用和立体位阻等作用力协同作用的过程.与未衍生的环糊精手性固定相相比,羧甲基-β-环糊精手性固定相具有更好的分离效果.%A reversed phase high performance liquid chromatographic method was developed using carboxymethyl-β-cyclodextrin chiral stationary phase for enantioseparation of seventeen kinds of cis-β-lactams enantiomers. Most of the compounds could get base-line separation. The effects of mobile phase pH, salt type and concentration, as well as mobile phase proportion were discussed. The results showed that ( 0. 10%NH4 Ac+FA ) ( pH= 5. 0 )-MeOH ( 70 : 30, volume ratio ) was the optimum condition for most of chiral compound. Under the optimum condition, the 7 compounds for CA series could get base-line separation except for compound 18CA, the best resolution values for compounds 15CA and 17CA were 1. 71 and 1. 74, respectively. The resolution values for seven EA compounds were between 1. 00 and 1. 50 which was nearly close to base-line separation except for compounds 18EA and 22EA. The resolution values for three BA compounds were close to 1. 00. Structures of analytes also played important role in chiral separation. The results indicated that better resolution could be obtained if the analyte with proper size matching cyclodextrin cavity. Hydrogen bond interaction between the substituents on the cyclodextrin derivative and the analytes and smaller steric hindrance were also good for enantioseparation. Smaller steric hindrance making analytes easily penetrate into cyclodextrin cavity was beneficial to enantioseparation. A tentative chiral recognition mechanism was proposed after a comprehensive analysis of the influencing factors for enantioseparation using compound 15CA as example. Inclusion interaction, hydrogen bond interaction, dipole-dipole interaction and steric hindrance were found to exert synergistic effects on enantioseparation. However, the inclusion interaction between the analytes and the cyclodextrin was the primary role for enantioselective recognition. In comparison with native β-CD CSP , CM-β-CD CSP exhibited enhanced enantioseparation.
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