ENANTIOSEPARATION OF ORCIPRENALINE, BETAXOLOL, AND PROPRANOLOL USING HPLC AND NEW CHIRAL REAGENTS BASED ON 1,5-DIFLUORO-2,4-DINITROBENZENE

Diastereomers of three -blockers (orciprenaline, betaxolol, and propranolol) were synthesized using three new chiral derivatizing reagents that were prepared by substituting one fluorine atom in 1,5-difluoro-2,4-dinitrobenzene with two chirally pure amines and one L-amino acid. The reagents were characterized using ultraviolet-visible spectroscopy, infrared spectroscopy, elemental analysis, and proton nuclear magnetic resonance. Diastereomers were synthesized under microwave irradiation at 50s at 80% of 800W and also by stirring for 50min at 45 degrees C. The diastereomers were separated by reversed-phase high-performance liquid chromatography on a C-18 column with detection at 340nm using acetonitrile and aqueous trifluoroacetic acid as the mobile phase components. The conditions of derivatization and chromatographic separation were optimized. The method was validated for accuracy, precision, limit of detection, and limit of quantification.