[Enantiomeric separation of mandelic acid and its analogues by high performance liquid chromatography with 2,6-di-O-pentyl-beta-cyclodextrin coated symmetry C8 column].

2,6-Di-O-pentyl-beta-cyclodextrin, synthesized from beta-CD in dimethyl sulfoxide (DM-SO), was dynamically coated on a Symmetry C8 column through hydrophobic interaction. Using the coated column, the resolution of six racemic mixtures of mandelic acid and its analogues by reversed-phase high performance liquid chromatography was achieved: (+/-)-mandelic acid, (+/-)-mandelic acid methyl ester, (+/-)-mandelic acid ethyl ester, (+/-)-2-phenylglycine, (+/-)-phenylsuccinic acid and (+/-)-benzoin. The enantiomeric separation mechanism is discussed. The method can be applied conveniently to determine the enantiomeric excess of mandelic acid and its analogues.