CHIRAL INTERACTIONS OF THE FLUOROETHER ANESTHETICS DESFLURANE, ISOFLURANE, ENFLURANE, AND ANALOGS WITH MODIFIED CYCLODEXTRINS STUDIED BY CAPILLARY GAS-CHROMATOGRAPHY AND NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY- A SIMPLE METHOD FOR COLUMN-SUITABILITY SCREENING
K. Ramig et al., CHIRAL INTERACTIONS OF THE FLUOROETHER ANESTHETICS DESFLURANE, ISOFLURANE, ENFLURANE, AND ANALOGS WITH MODIFIED CYCLODEXTRINS STUDIED BY CAPILLARY GAS-CHROMATOGRAPHY AND NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY- A SIMPLE METHOD FOR COLUMN-SUITABILITY SCREENING, Tetrahedron, 52(1), 1996, pp. 319-330
Eighteen chiral analogues of the chiral fluoroether anesthetics desflu
rane, isoflurane, and enflurane are synthesized and studied by capilla
ry GC on four cyclodextrin-derived stationary phases. Trends in separa
bility and elution order of enantiomers are related to structure and a
bsolute configuration. In particular,a very large separation factor is
found for the commercial anesthetic desflurane using Lipodex(R) E sta
tionary phase, suggesting that a preparative enantiomer separation is
possible. One of the stationary phases, Cyclodex(R) G-TA, is found to
be a chiral shift reagent for several of the fluoroethers. A rough cor
respondence is found relating the enantiomeric separation factor of a
fluoroether and the chemical shift differences between its H-1 and F-1
9 nuclei in the NMR spectrum. Based on this data, it is proposed that
a simple NMR experiment can screen chiral stationary phases prior to a
desired gas chromatographic enantiomer separation of a given chiral c
ompound.