β-环糊精键合手性固定相分离苯并恶嗪类对映体

Separation of benzoxazine enantiomers on β-cyclodextrin bonded chiral stationary phases

研究了在反相高效液相色谱模式下,基于点击化学的β-环糊精手性固定相对苯并恶嗪类对映体的手性分离情况。考察了流动相中有机改性剂的类型和比例、缓冲盐的浓度和pH值对分离的影响。考察结果表明:乙腈作为有机改性剂比甲醇更有利于苯并恶嗪对映体的分离;乙酸三乙胺缓冲盐体积分数从0.1%增大到1.0%时,苯并恶嗪对映体的保留时间和分离度都随之减小,在pH4.1时苯并恶嗪对映体具有最大分离度。因此确定乙腈和体积分数为0.1%的乙酸三乙胺缓冲盐流动相(pH4.1)为最佳分离条件。分离机理研究结果表明,固定相和样品之间的包容络合相互作用以及样品和固定相之间的氢键作用,是样品得以分离的基础。本研究为进一步深入研究β-环糊精固定相提供了实验基础,同时也证明了点击化学在手性环糊精固定相制备中具有极大潜力。

Chiral separation of benzoxazine enantiomers was studied on click chemistry based beta-cyclodextrin stationary phases under reversed-phase high performance liquid chromatographic mode.The effects of the type and percentage of the organic modifier,the concentration of triethylammonium acetate buffer（TEAA）,and pH on enantioselective separation were examined and studied.It was demonstrated that acetonitrile was better for the chiral separation of benzoxazine enantiomers than methanol.It was observed that the retention time and the resolution of benzoxazine enantiomers decreased with the increase of the volume ratio of TEAA from 0.1% to 1.0%.The separation of benzoxazine enantiomers was of the maximum resolution at pH 4.1.With the optimized mobile phase of the mixture of acetonitrile and 0.1% TEAA（pH 4.1）,all the enantiomers were separated at the baseline.The chiral recognition mechanism is also discussed.The separation was probably based on the inclusion complex interaction and the hydrogen bonding between enantiomers and chiral stationary phases.This work provided the experience for the intensive study of click beta-cyclodextrin bonded stationary phases,and it also illustrated the potential of click chemistry in the preparation of beta-cyclodextrin based chiral stationary phase.