| Optical isomers occurring widely in nature display different biochemical and pharmacological effects. Thus, with the great interest in stereochemistry that today pervades most branches of chemistry and biochemistry, assigning absolute configuration and preparatively obtaining optical isomers in high enantiomeric purity are urgently needed.;The resolution of optical isomers by HPLC has been investigated by two different methods. The first approach is the use of chiral solvents or sorbents where a diastereomeric complex is formed by solute-solvent or solute-sorbent interactions not involving the formation of a covalent bond. The second approach is the differentiation of enantiomers by derivatization with suitable chiral reagents, where by the diastereomers are separated on an optically inactive stationary phase.;Liquid chromatographic separation of enantiomers with columns containing chiral phase is another method to solve the problem of enantiomeric purity determinations, assignments of absolute configuration and preparative resolution of racemates.;The aim of this research was to develop efficient and useful chiral stationary phases for HPLC. Our approach to this problem was to synthesize a series of specific chiral compounds, using optically active terpene compounds such as camphor, (alpha)-pinene and (beta)-pinene. The optically active terpene nucleus homologues were bonded covalently to a silica gel matrix through the reaction of their N-succinimide-activated esters with an aminopropyl silanized silica. Nine synthesized chiral stationary phases were packed in HPLC columns using isopropanol as the packing solvent. The chiral stationary phases were evaluated in the resolution of enantiomers of the pharmaceutically interesting racemates amphetamine, ephedrine, and the amino acid, phenylalanine methyl ester. Unfortunately, resolutions were not obtained for any of the above mentioned enantiomers. (Abstract shortened with permission of author.);Chromatography is well know as a very efficient technique of separation and resolution of enantiomers. For analytical purposes, high performance liquid chromatography (HPLC) has been shown to be the most efficient because of its high resolution, high sensitivity and versatility. |
