Zhong Qiqing, He Lingfeng, Beesley Thomas E, Trahanovsky Walter S, Sun Ping, Wang Chunlei, Armstrong Daniel W
Department of Chemistry, Iowa State University, Ames, IA 50011, USA.
J Chromatogr A. 2006 May 19;1115(1-2):19-45. doi: 10.1016/j.chroma.2006.02.065. Epub 2006 Apr 18.
The synthesis and evaluation of new dinitrophenyl (DNP) substituted beta-cyclodextrin (beta-CD) chiral stationary phases (CSPs) for the enantioseparation of various classes of chiral analytes by HPLC are presented. The dinitrophenyl substituted beta-CD derivatives are synthesized and covalently bonded to functionalized 5 microm spherical porous silica gel. These are the first reported derivatized cyclodextrin which contains pi-electron deficient substituents (i.e., pi-acidic moieties). The column performance in terms of their ability to separate enantiomers is evaluated. A variety of different dinitro-substituted aryl groups are investigated and compared. The pH of the mobile phase buffers, the buffer composition, the number and position of the dinitro groups on the phenyl ring substituent, the degree of substitution, and the bonding strategy all greatly affect the performance of the CSPs. A large variety of racemic compounds have been separated successfully on these CSPs. The bonded dinitrophenyl-derivatized cyclodextrins are stable in all three mobile phase modes, namely, the reversed-phase, polar organic, and normal phase modes. No degradation in column performance was observed in any mode of operation even after more than 1000 injections. The analytical applicability of these types of CSPs for enantiomeric separations is discussed in detail.
本文介绍了用于高效液相色谱法对各类手性分析物进行对映体分离的新型二硝基苯基（DNP）取代β-环糊精（β-CD）手性固定相（CSP）的合成与评价。合成了二硝基苯基取代的β-CD衍生物，并将其共价键合到功能化的5微米球形多孔硅胶上。这些是首次报道的含有缺π电子取代基（即π-酸性基团）的衍生化环糊精。评估了它们分离对映体的柱性能。研究并比较了多种不同的二硝基取代芳基。流动相缓冲液的pH值、缓冲液组成、苯环取代基上二硝基的数量和位置、取代度以及键合策略均对CSP的性能有很大影响。在这些CSP上已成功分离了多种外消旋化合物。键合的二硝基苯基衍生化环糊精在反相、极性有机和正相这三种流动相模式下均稳定。即使在超过1000次进样后，在任何操作模式下均未观察到柱性能下降。详细讨论了这类CSP在对映体分离方面的分析适用性。
