Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, PR China; State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, PR China.
Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing, 210009, PR China; State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, PR China.
Talanta. 2020 Sep 1;217:121083. doi: 10.1016/j.talanta.2020.121083. Epub 2020 Apr 26.
Recently, chiral ionic liquids have attracted increasing attention in analytical chemistry. However, only a few papers focus on the application of them in visual chiral recognition. Herein, two functionalized chiral ionic liquids derived from (S)-mandelic acid (1-butyl-3-methylimidazolium mandelate, CIL1 and N-butyl-N-methylpyrrolidinium mandelate, CIL2) were prepared for visual chiral recognition of aromatic amino acids for the first time. In the presence of Cu(II) and appropriate solvents, visual enantiomeric responses of phenylalanine, tryptophane, tyrosine and phenylglycine were observed. Relying on solubility or color differences, all chiral recognition could be finished within 5 min. The potential mechanism was investigated by means of infrared spectroscopy, ultraviolet spectroscopy, thermal gravity analysis, elemental analysis and scanning electron microscope. Results revealed that CuSO interacted with CIL1 and D-tryptophane in the ratio of 1:1.96:0.43 in relevant precipitate, and the different stability of complex was responsible for the chiral recognition. In addition, resolution of racemic tryptophane was performed, which offered excellent enantiomeric excess values (94.2% for CIL1 and 95.1% for CIL2 in solid phase). The proposed ionic liquids had strong enantioselectivity for aromatic amino acids and great potential in visual chiral recognition.
最近，手性离子液体在分析化学中受到了越来越多的关注。然而，只有少数几篇论文关注它们在手性识别中的应用。本文首次制备了两种源于(S)-扁桃酸的功能化手性离子液体(1-丁基-3-甲基咪唑𬭩扁桃酸盐，CIL1 和 N-丁基-N-甲基吡咯烷𬭩扁桃酸盐，CIL2)，用于芳香族氨基酸的可视化手性识别。在 Cu(II)和适当溶剂的存在下，观察到苯丙氨酸、色氨酸、酪氨酸和苯甘氨酸的对映体的可视化响应。依靠溶解度或颜色差异，所有的手性识别都可以在 5 分钟内完成。通过红外光谱、紫外光谱、热重分析、元素分析和扫描电子显微镜研究了潜在的机制。结果表明，CuSO4与 CIL1 和 D-色氨酸以 1:1.96:0.43 的比例在相关沉淀中相互作用，而配合物的不同稳定性是手性识别的原因。此外，还实现了外消旋色氨酸的拆分，得到了出色的对映体过量值(在固相中 CIL1 为 94.2%，CIL2 为 95.1%)。所提出的离子液体对芳香族氨基酸具有很强的对映选择性，在手性识别中具有很大的潜力。
