The optical purities of chiral derivatization reagents 4-(N,N-dimethylaminosulphonyl)_7-(3-aminopyrrolidin-l-yl)-2,1,3-benzoxadiazole (DBD-APys), 4_(aminosulphonyl)_7-(3-aminopyrrolidin-1-yl)_2,1,3-benzoxadiazole (ABD-APys) and 4-nitro-7-(3-aminopyrrolidin-1-ylJ-2,1,3-benzoxadiazole (NBD-APys) were determined by chromatographic separation with an Ultron ES-PHCD (/3-cyclodextrin phenylcarbamate derivative) chiral stationary phase column. With the exception of ( + )-4-nitro-7-(3-aminopyrrolidin-l-yl)-2,l,3-benzoxadiazole
which was found to have a purity of 99.5%, the enantiomers were determined to be more than 99.8% pure. The rate of the derivatization reaction for each enantiomer of DBD-APy at room temperature in the presence of the carboxylic acid reaction promoters 2,2'-dipyridyl disulphide (DPDS) and triphenylphosphine (TPP), was essentially the same for each enantiomer of naproxen. The reaction rates at 50Β°C were comparable at room temperature. When the derivatizations with DBD-APy and NBD-APy were carried out in the presence of diethyl phosphorocyanidate (DEPC) instead of DPDS and TPP quantitative derivatizations were not obtained even after a prolonged reaction time. The diastereomers derived from anti-intlammatory drugs and N-acetylamino acid enantiomers were efficiently resolved by both normal-phase (R, = 2.58-7.60) and reversed-phase (R, = 1.62-6.96) chromatography. The resolution of carboxylic acid enantiomers by liquid chromatography with laser-induced fluorescence &IF) detection was also investigated. The minimum detectable levels by reversed-phase chromatography with an argon ion laser at 488 nm were 29 fmol of ABD-APy-Nap, 11 fmol of DBD-APy and 2.9 fmol of NBD-APy. Ibuprofen enantiomers added to rat plasma and human urine were completely separated by an ODS column with water-acetonitrile as eluent without interference from endogenous compounds. Sensitive detection was achieved with a commercially available LIF detector. Negligible mutagenicity of the reagents was observed by the Ames test using Salmonella typhimutium strains TAlOO and TA98.