A preparative and solution study of a modified beta-cyclodextrin and its europium(III) complex, and their interactions with racemic amino acid anions

© CSIRO 2001 The synthesis and characterization of 6A-deoxy-6A-(1,4,7-tri(carboxylatomethyl)-1,4,7,10-tetraazacyclododecan-10-yl)-β-cyclodextrin (1b) are reported. A fluorescence lifetime study of its Eu3+ complex (1c) is consistent with one water coordinating Eu3+ in addition to hepta-coordination by (1b). 1H NMR studies are consistent with (1b) forming host–guest complexes with (R/S)-histidinate (2a), (R/S)-tyrosinate (2b), (R/S)-phenylalaninate (2c), and (R/S)-tryptophanate (2d), with enantioselectivity shown for (2b). Similar studies are consistent with (1c) complexing (2a–d), with enantioselectivity shown for (2a).Suzanna D. Kean, Christopher J. Easton, Stephen F. Lincoln and David Parke