Amino acid recognition of pyridine bis(oxazoline)–copper(II) complex in aqueous solvent

Enantioselective recognition of amino acids has been studied with C2-symmetric chiral pyridine bis(oxazoline)–copper(II) complexes at physiological pH condition. UV–visible titration revealed strong binding of submillimolar dissociation constant between pyridine bis(oxazoline)–copper(II) complex and amino acids in aqueous solution. Moderate selectivity of up to 2:1 between d- and l-amino acids was achieved. The enantiomers were baseline resolved by capillary electrophoresis, using the bis(l-lysine)–copper(II) complex as a chiral selector.