title: High-performance liquid chromatographic chiral separation of beta2-homoamino acids.
abstract: Reversed-phase high-performance liquid chromatographic methods were developed for the separation of enantiomers of eleven unnatural beta(2)-homoamino acids on chiral stationary phases containing macrocyclic glycopeptides (teicoplanin-containing Chirobiotic T and T2) or the macrocyclic peptide teicoplanin aglycone (Chirobiotic TAG) as chiral selectors. The effects of the organic modifier, the mobile phase composition, temperature, and the structures of the analytes on the separations were investigated. Separations were carried out at constant mobile phase compositions in temperature range 7-45 degrees C and the changes in enthalpy, Delta(DeltaH(o)), entropy, Delta(DeltaS(o)), and free energy, Delta(DeltaG(o)), were calculated. The -Delta(DeltaG(o)) values obtained on the three columns indicated that Chirobiotic TAG, without sugar units, may promote the interactions of the enantiomers of beta(2)-homoamino acids with branched alkyl or aryl side-chains, whereas for beta(2)-homoamino acids with alkyl side-chains Chirobiotic T and T2 seem to be more favorable. The elution sequence was determined in some cases and was observed to be R < S.
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Szeged, H-6720 Szeged, Hungary.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Pataj
authors.forename: Robert
authors.initials: R
authors.lastname: Berkecz
authors.forename: István
authors.initials: I
authors.lastname: Ilisz
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Misicka
authors.forename: Dagmara
authors.initials: D
authors.lastname: Tymecka
authors.forename: Ferenc
authors.initials: F
authors.lastname: Fülöp
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Armstrong
authors.forename: Antal
authors.initials: A
authors.lastname: Péter
mesh_terms: D000596:Amino Acids / Q000737:chemistry* / Q000302:isolation & purification*; D000900:Anti-Bacterial Agents / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006020:Glycopeptides / Q000737:chemistry; D047028:Macrocyclic Compounds / Q000737:chemistry; D013237:Stereoisomerism; D013696:Temperature; D013816:Thermodynamics
chemical_list: D000596:Amino Acids; D000900:Anti-Bacterial Agents; D006020:Glycopeptides; D047028:Macrocyclic Compounds