Ilona Sztruhar

Determination of the enantiomeric composition of chiral carboxylic acids using chiral derivatization and HPLC

SummaryThe enantiomers of chiral carboxylic acids were separated as their diastereomeric amides with (1R,2R)-(−)-1-(4-nitrophenyl)-2-amino-1,3-propanediol (“levobase”) and with “dextrobase” (the enantiomer of levobase) by high-performance liquid chromatography using a conventional C-18 column and various solvent systems containing acetonitrile, methanol, water, and phosphoric acid.

High-performance liquid chromatography of 8-azagonane-12-one derivatives and their oximes : II. Separation of Optical Isomers

Abstract The high-performance liquid chromatographic separation of optical isomers of some biologically active 8-azagonane-12-one derivatives and their oximes b

Stereochemistry and enantiomeric purity of a novel anxiolytic agent, deramciclane fumarate

The synthesis, stereostructure, and enantiomeric separation by chromatography of a new, chiral anxiolytic agent, deramciclane fumarate (2, (-)-[1R,2S,4R]-2-(2-dimethylaminoethoxy)-2-phenyl-1,7, 7-trimethylbicyclo[2.2.1]heptane fumarate, EGIS-3886), is described. The optical antipode and the racemate of compound 2 were also prepared. The structure was determined by single crystal X-ray diffraction analysis. The enantiomeric separation was accomplished by HPLC on Chiralcel OD (250 x 4.6 mm; 10 microm) and hexane-ethanol (99.5:0.5) as mobile phase at room temperature. The enantiomeric purity of the synthesized drug substance proved to be very high (>99. 9%). Some statements published earlier on the stereostructure of deramciclane fumarate are critically discussed.

Direct determination of the racemate ratio of labetalol hydrochloride by HPLC

SummaryA direct, isocratic, reversed phase HPLC procedure is developed for the separation of the diastereomeric racemates of labetalol, a combined α- and β-adrenoreceptor antagonist. The aminoalcohol-type diastereomers were resolved on a C18 column using methanolwater-25% ammonia 27-75-2 mobile phase and detection at 220nm. The procedure is simple and convenient to carry out. The method may be of use in the determination of the individual diastereomeric racemates of labetalol in different forms such as bulk substance, pharmaceutical dosage preparations and biological fluids.