Fast Super/Subcritical Fluid Chromatography Enantiomeric Separations of Dihydrofurocoumarin Derivatives with Macrocyclic Glycopeptide Stationary Phases

Summary

Twenty-four chiral dihydrofurocoumarin derivatives and structurally related compounds were separated using super/subcritical fluid chromatography (SFC) on three macrocyclic glycopeptide chiral stationary phases (CSPs). All the dihydrofurocoumarin derivatives could be resolved on at least one of the macrocyclic glycopeptide CSPs, and the Chirobiotic T column showed the best enantioselectivity for 21 of the dihydrofurocoumarins studied. The Chirobiotic TAG and Chirobiotic R CSPs separated similar numbers of chiral dihydrofurocoumarin derivatives (16 on Chirobiotic TAG and 15 on Chirobiotic R), but the Chirobiotic TAG column baseline resolved more samples than the Chirobiotic R column under similar experimental conditions. All separations were done isocratically with an outlet pressure regulated at 100 bar, a column temperature of 31 °C, and a flow rate of 3.0 mL min^-1. Various amounts of methanol ranging from 2 to 25% (v/v) were added to the supercritical carbon dioxide in order to optimize the enantiomeric separations. All of the separations were completed in less than 15 min, and 81% of the separations were done in less than 10 min. The separation speed is one of the main advantages of SFC.