Folmer-Andersen J Frantz, Lynch Vincent M, Anslyn Eric V
Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712, USA.
J Am Chem Soc. 2005 Jun 8;127(22):7986-7. doi: 10.1021/ja052029e.
A new method is described for the determination of optical purity of alpha-amino acid samples in protic media. No derivatization of the analyte or multistep synthesis is required, and high accuracy is obtained from the colorimetric output. Chiral discrimination is achieved through the use of an optically pure trans-1,2-diaminocyclohexane-derived Cu(II)-containing host that differentiates amino acid enantiomers by a factor of about 2. Enantioselective signaling arises from the implementation of an indicator displacement assay based on competitive Cu(II) coordination involving the chiral Cu(II)-containing host, the amino acid guest, and a metal ion indicator. The molecular structure of the host/guest complex was determined by X-ray analysis and exhibits chelation of the Cu(II) center by the amino acid to provide substrate organization.
描述了一种用于测定质子介质中α-氨基酸样品光学纯度的新方法。无需对分析物进行衍生化或多步合成，并且通过比色输出可获得高精度。通过使用光学纯的反式-1,2-二氨基环己烷衍生的含铜（II）主体来实现手性识别，该主体可将氨基酸对映体区分约2倍。对映选择性信号源于基于竞争性铜（II）配位的指示剂置换测定法的实施，该配位涉及含手性铜（II）的主体、氨基酸客体和金属离子指示剂。通过X射线分析确定了主体/客体配合物的分子结构，该结构显示氨基酸对铜（II）中心的螯合作用，从而提供底物组织。
