Rapid separations of diacyl- and dialkylglycerol enantiomers by high performance liquid chromatography on a chiral stationary phase.

Rapid and practical separations of 1,2- and 2,3-diacyl- and dialkyl-sn-glycerol enantiomers as their 3,5-dinitrophenyl-urethane derivatives were carried out by normal-phase high performance liquid chromatography on a chiral stationary phase, N-(R)-1-(alpha-naphthyl)ethylaminocarbonyl-(S)-valine chemically bonded to gamma-aminopropyl silanized silica. Complete separations of the racemates into enantiomers were achieved for both of the diacyl- and dialkylglycerols within 10 min using a stainless steel column (25 cm long) packed with the 5-mu particles, an isocratic elution with a mixture of hexane/ethylene dichloride/ethanol as a mobile phase and a UV detector. The sn-1,2-enantiomers were eluted ahead of the corresponding sn-2,3-enantiomers. Satisfactory separation of the sn-1,3-diacylglycerols from the corresponding enantiomers and the separation of the homologues differing in acyl and alkyl groups were also observed. The formations of hydrogen bonding and charge transfer complex between the urethane derivatives and the stationary phase may contribute to the enantiomer separations.