Jadaud P, Wainer I W
St. Jude Children's Hospital, Memphis, Tennessee 38105.
Chirality. 1990;2(1):32-7. doi: 10.1002/chir.530020105.
The enantioselective and diastereoselective resolutions of the stereoisomers of N alpha-aspartyl-phenylalanine 1-methyl ester (APME) have been accomplished on an HPLC chiral stationary phase based upon alpha-chymotrypsin (the ACHT-CSP) with observed enantioselectivities (alpha 1) for the DL-/LD-enantiomer of as high as 29.17 and for the DD-/LL-enantiomers of as high as 28.97. In addition, the effect on the chromatographic retention of the APME stereoisomers of the activity of the ACHT and the composition of the mobile phase--structure of the anionic component, molarity, and pH--have been studied. The results of this study suggest that the aspartyl moiety and/or the aspartyl-phenylalanine amide linkage play key roles in the observed enantioselectivity; the APME stereoisomers containing L-phenylalanine, i.e., DL- and LL-APME, bind at a different site in the ACHT molecule (the L-Phe site) than the APME stereoisomers containing D-phenylalanine (the D-Phe site); and the observed enantioselectivity is a measure of the difference in the binding affinities at the two sites rather than the consequence of differential affinities at a single site.
基于α-胰凝乳蛋白酶的高效液相色谱手性固定相（ACHT-CSP）已实现了Nα-天冬氨酰-苯丙氨酸1-甲酯（APME）立体异构体的对映体选择性和非对映体选择性拆分，观察到的DL-/LD-对映体的对映体选择性（α1）高达29.17，DD-/LL-对映体的对映体选择性高达28.97。此外，还研究了ACHT活性和流动相组成（阴离子组分结构、摩尔浓度和pH值）对APME立体异构体色谱保留的影响。该研究结果表明，天冬氨酰部分和/或天冬氨酰-苯丙氨酸酰胺键在观察到的对映体选择性中起关键作用；含有L-苯丙氨酸的APME立体异构体，即DL-和LL-APME，在ACHT分子中的结合位点（L-Phe位点）与含有D-苯丙氨酸的APME立体异构体（D-Phe位点）不同；观察到的对映体选择性是两个位点结合亲和力差异的一种度量，而不是单个位点差异亲和力的结果。
