New chiral molecular tweezers 1～4 have been synthesized by using deoxycholic acid as a spacer to bridge the different aromatic amines. Their structures were confirmed by IR, ^1H NMR and elemental analysis. Enantioselective recognition properties of these molecular tweezers for amino acid methyl esters have been investigated by UV-vis spectra titration in CHCl3 at 25℃. The results indicate that molecular tweezers 1～4 not only recognize all amino acid methyl esters examined but also possess higher selectivity for D-amino acid methyl esters. The recognition ability and selectivity are discussed from the viewpoint of the size/shape-fit and geometrical complementary relationship between the molecular tweezers and amino acid methyl esters.

Key words: CARBAMIC ACID ESTER, DEOXYCHOLIC ACID, ENANTIOMORPH, SELECTIVITY, AMINO ACID, OLECULAR RECOGNITION