Effect of the Modification of the Free Carboxylic Acid Groups of an HPLC Chiral Stationary Phase Based on (+)-(18-Crown-6)-2,3,11,12-tetracarboxylic Acid on the Chiral Recognition

Ala 2.59(L) 1.29 1.13 0.88(L) 1.29 1.28 0.86(L) 1.33 0.89Cys 2.95(L) 1.12 0.49 0.93(L) 1.16 0.42 1.01(L) 1.17 0.38His 6.42(L) 1.46 1.10 1.24(L) 1.41 0.91 1.65(L) 1.44 0.87Leu 1.38(L) 1.34 1.24 0.41(L) 1.24 0.54 0.46(L) 1.46 1.39Pgy 4.58(L) 2.16 4.50 1.28(L) 2.26 2.44 1.54(L) 2.23 3.97Phe 1.69(L) 1.38 1.49 0.50(L) 1.39 1.14 0.59(L) 1.51 1.46Ser 2.24(D) 2.34 3.47 0.72(D) 2.29 2.63 0.96(D) 1.92 1.59Val 0.71(L) 1.43 1.57 0.20(L) 1.40 0.73 0.22(L) 1.43 1.10