Molecular recognition study on a supramolecular system. 10. Inclusion complexation of modified β-cyclodextrins with amino Acids: enhanced enantioselectivity for L/D-leucine

摘要

The novel β-cyclodextrin (β-CD) derivatives bearing a m-toluidinyl or (9-fluroenyl)alkylamino moiety have been synthesized by a convenient method in 45/100 and 66/100 yields, respectively. The stability constants (K_s) and Gibbs free energy changes (-ΔG) for inclusion complexation of mono-[6-(m- toluidinyl)6-deoxy]-β-cyclodextrin 1 and mono-[6-[(9-fluorenyl)alkylamino]-6-deoxy]-β-cyclodextrin 2 with various L/D-amino acids have been examined by the fluporescence spectrum method in buffered aqueous solution (pH=7.20) to 20-23 deg C.