Chiral Separations Using Dipeptide Polymerized Surfactants: Effect of Amino Acid Order
作者:Eugene Billiot、Javier Macossay、Stefan Thibodeaux、Shahab A. Shamsi、Isiah M. Warner
DOI:10.1021/ac9709561
日期:1998.4.1
Chiral separations using various polymerized dipeptide surfactants in electrokinetic capillary chromatography (EKC) are investigated. The two main dipeptide surfactants used in this study were sodium N-undecylenyl-l-valine-l-leucine (l-SUVL), and sodium N-undecylenyl-l-leucine-l-valine (l-SULV). These studies were performed in order to determine if the order of amino acids in dipeptide surfactants is important in terms of chiral recognition and separations. Both the monomer and the polymer of these two surfactants were compared for the separation of two model atropisomers, (±)-1,1‘-bi-2-naphthol (BOH) and (±)-1,1‘-bi-2-naphthyl-2,2‘-diyl hydrogen phosphate (BNP). Some advantages and disadvantages of the polymer relative to the monomer are discussed. Four other surfactants, the polymers of sodium N-undecylenyl-l-leucine-l-leucine (l-SULL), sodium N-undecylenyl-l-valine-l-valine (l-SUVV), sodium N-undecylenyl-l-valine (l-SUV), and sodium N-undecylenyl-l-leucine (l-SUL), were also used in this study, and their performance was compared to that of poly(l-SULV). These data show conclusively that the order of amino acids in dipeptide surfactants has a dramatic effect on chiral recognition. Our investigations indicate that poly(l-SULV) provides the best enantioselectivity among the four dipeptide and two single amino acid surfactants for the separation of BNP and BOH. The advantages of poly(l-SULV) are demonstrated via the ultrafast separation of the enantiomers of BNP and BOH in less than 1 min.
使用电动力学毛细管色谱法(EKC)研究了各种聚二肽表面活性剂的手性分离。本研究中使用的两种主要二肽表面活性剂是钠N-十一烯基-L-缬氨酸-L-亮氨酸(L-SUVL)和钠N-十一烯基-L-亮氨酸-L-缬氨酸(L-SULV)。这些研究的目的是确定二肽表面活性剂中氨基酸的顺序是否在手性识别和分离方面起着重要作用。比较了这两种表面活性剂的单体和聚合物,用于分离两个模型旋转异构体,即(±)-1,1'-双-2-萘酚(BOH)和(±)-1,1'-双-2-萘基-2,2'-二基磷酸氢(BNP)。讨论了聚合物相对于单体的一些优点和缺点。本研究还使用了其他四种表面活性剂,即钠N-十一烯基-L-亮氨酸-L-亮氨酸(L-SULL)、钠N-十一烯基-L-缬氨酸-L-缬氨酸(L-SUVV)、钠N-十一烯基-L-缬氨酸(L-SUV)和钠N-十一烯基-L-亮氨酸(L-SUL)的聚合物,并将其性能与聚(L-SULV)进行了比较。这些数据显示,二肽表面活性剂中氨基酸的顺序对手性识别有显著影响。我们的研究表明,在四种二肽和两种单氨基酸表面活性剂中,聚(L-SULV)在分离BNP和BOH方面提供了最佳的对映选择性。通过在不到1分钟的时间内超快分离BNP和BOH的对映体,展示了聚(L-SULV)的优势。