Electrokinetic chromatography employing an anionic and a cationic beta-cyclodextrin derivative.
beta-Cyclodextrin, 1, can act as a chiral buffer additive in capillary zone electrophoresis (CZE) owing to its ability to form diastereomeric complexes with the enantiomers of ionic compounds. Reaction of 1 with 2,3-epoxy-propyltrimethylammonium chloride gave preponderantly 6-O-(2-hydroxy-3-trimethylammoniopropyl) derivatives (2) of varying degrees of substitution (d.s.). Analogous reaction of 1 with 1,3-propanesultone yielded 6-O-(sulfo-n-propyl) derivatives (SPE-beta-CD, 3) of varying d.s. The purity and the d.s. of 2 and 3 were determined by 1H NMR and electrospray ionization mass spectrometry (ESI-MS). These charged beta-cyclodextrin derivatives were used for the chromatographic enantiomer separation of a series of neutral barbiturates, of chlorthalidone, terbutaline, warfarin, salbutamol and brompheniramine by cyclodextrin electrokinetic chromatography (CD-EKC). During the separation of chlorthalidone with 3 as chiral additive, a reversible interconversion of the enantiomers (enantiomerization) was observed at temperatures below 20 degrees C.
Jakubetz
H
H
Institut für Organische Chemie, Universität Tübingen, Germany.
Juza
M
M
Schurig
V
V
D000838:Anions; D002412:Cations; D002752:Chlorthalidone / Q000737:chemistry; D002845:Chromatography / Q000379:methods*; D003505:Cyclodextrins / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods; D015394:Molecular Structure; D047392:beta-Cyclodextrins
D000838:Anions; D002412:Cations; D003505:Cyclodextrins; D047392:beta-Cyclodextrins; C031215:betadex; D002752:Chlorthalidone