A study of chiral recognition for NBD-derivatives on a Pirkle-type chiral stationary phase

A chiral stationary phase (CSP 1) derived from an (S)-N-3,5-dinitrobenzoyl- 1-naphthylglycine showed excellent enantiomeric separation for amino acid d erivatives with a fluorogenic reagent, 4-fluoro-7-nitro-2,1,3-benzoxadiazol e (NBD-F), in high-performance liquid chromatography (HPLC). We compared el ution profiles (separation factor and elution order) of NBD-amino acids and their analogs on HPLC, to determine the diastereomeric complex between the chiral moiety of CSP 1 and NBD-amino acid, which is responsible for the ch iral recognition. H-1-NMR studies of a mixture of model compound of CSP 1 a nd NBD-Ala suggest that the diastereomeric complex is composed of two hydro gen bonding sites at the amino proton and oxygen atom, and a pi-pi interact ion by the benzofurazan structure (2,1,3-benzoxadiazole) of NBD-amino acid. Furthermore CSP 1 was able to separate esters, amides and alpha -methyl am ino acids derivatized with NBD-F. Copyright (C) 2001 John Wiley & Sons, Ltd .