title: Direct high-performance liquid chromatographic separation of unusual secondary amino acids and a comparison of the performances of Chirobiotic T and TAG columns.
abstract: Two macrocyclic glycopeptide antibiotic-type chiral stationary phases (CSPs) based on native teicoplanin and teicoplanin aglycone, Chirobiotic T and TAG, respectively, were evaluated with regard to the high-performance liquid chromatographic separation of the enantiomers of 10 secondary alpha-amino acids (imino acids). The chromatographic results are given as the retention, separation and resolution factors, together with the enantioselective free energy difference corresponding to the separation of the enantiomers. By application of these two CSPs, excellent resolutions were achieved for the investigated compounds by using reversed-phase mobile mode systems. The separation conditions were optimized by variation of the mobile phase composition. The difference in enantioselective free energy between the aglycone CSP and the teicoplanin CSP for these particular amino acids ranged between 0.70 and -1.83 kJ mol(-1). It was established that better enantioseparations of the secondary alpha-amino acids were attained in most cases on the aglycone CSP.
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary. apeter@chem.u-szeged.hu
authors.forename: Antal
authors.initials: A
authors.lastname: Péter
authors.forename: Roland
authors.initials: R
authors.lastname: Török
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Armstrong
mesh_terms: D000596:Amino Acids / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids