In recent years there has been considerable interest in the synthesis and separation of enantiomers of organic compounds especially because of their importance in the biochemistry and pharmaceutical industry. Frequently the methods used for the separations, for monitoring the progress of an asymmetric synthesis or optical purity of the products are chromatographic with either liquids, gases, or...

An in situ approach involving a simple mix and shake method for testing the enantiopurity of primary, secondary and tertiary chiral amines and their derivatives, chiral amino alcohols, by (1)H-NMR spectroscopy is developed. The protocol involves the in situ formation of chiral ammonium borate salt from a mixture of C2 symmetric chiral BINOL, trialkoxyborane and chiral amines. The proposed conce...

The development of highly potent chiral discrimination methods that solve the problems of the diastereomer method is described. Explaining the significant results of separations of diastereomers having chiral centers separated by 13 - 27 bonds with reversed-phase HPLC was hitherto impossible. To attract more scientific interest toward the mechanism of the separation, the author proposes a hypot...

A simple reversed-phase chiral HPLC method has been developed and validated for direct separation of the enantiomers of zaltoprofen. Separation of the enantiomers was tested on numerous commercial chiral HPLC columns. Separation was best (resolution, RS = 3) on a Chiralcel OJ-RH stationary phase. Typical retention times of the S and R enantiomers were approximately 14 and 16 min, respectively. ...

Recent advances in membrane-based separations include chiral separations, nanofiltration, ion-permselectivity, gas separation and pervaporation. Novel chiral separations using enzymes and chiral surfactants as carrier have been achieved using facilitated-transport membranes. Graft-copolymeric membranes have been constructed that possess pH-controlled ion selectivity, and membranes have been mad...

A method for the separation of folinic acid diastereomers by capillary electrophoresis in chiral separation media was developed. Aiming to achieve a good separation of the anionic analytes, a newly synthesized cationic β-cyclodextrin derivative, mono-6-deoxy-6-piperdine-β-cyclodextrin, was applied as the chiral selector. The effect of background electrolyte pH, the concentration of the cyclodex...

Due to different physiological activities, the chromatographic separation of enantiomers is an important task in drug discovery and development. The determination of the enantiomeric excess (ee) is often done with supercritical fl uid chromatography (SFC) in combination with chiral stationary phases. Since fi nding the right stationary phase that provides separation of the enantiomers is diffi ...

Micellar electrokinetic chromatography (MEKC) and capillary electrochromatography (CEC) are two of the major capillary electrophoresis (CE) modes that have been interfaced to mass spectrometry (MS) for sensitive and selective analysis of chiral compounds. This research combines these two modes and expands their applications in chiral CE analysis. Chapter 1 is a review of amino acid based molecu...

The distribution behavior of ofloxacin enantiomers was examined in the aqueous and organic solvent of a two-phase system containing chiral selector L-tartarate. The effect of extraction equilibrium time, buffer pH, organic solvents and length of alkyl chain of L-tartarate on the partition coefficients and enantioselectivity of racemic ofloxacin were investigated, respectively. The L-tartara...