RESOLUTION OF THE ENANTIOMIERS OF EPHEDRINES USING (+ )一FLEC CHIRAL DERIVATIZATION AND REVERSED—PHASE LIQUID CHROMATOGRAPHY

An automatic and rapid reversed phase liquid chromatographic method for the resolution of enantiomers of four ephedrines using (+)- FLEC as on-line pre-column chiral derivatizing reagent has been devcloped.After dl-ephedrine,dl-pseudoephedrine,dl-norephedrine and dl-norpseudoephedrine were derivatized with the chiral reagent(+)- FLEC 1-( fluorenyl ) ethylchloroformate ,the resulting diastereomers were separated by using an acetontrile-water gradient elution on an ODS Hypersil column .This method was fully automated from sample derivatization to final report. Four enantiomersof ephedrines were well separated with resolution better that 1.5 . Thesensitivity was 1 0 pmol and reproducibility better than 1.0% RSD for retention time and 3 .0%fopeak area.