Chiral separations of piperidine-2,6-dione analogues on Chiralpak IA and Chiralpak IB columns by using HPLC

Recently, two new immobilized polysaccharides based CSPs, namely tris-(3,5-dimethylphenylcarbamate) derivatives of amylose and cellulose known as Chiralpak IA and Chiralpak IB were introduced, which may be used with a wide range of solvents including standard and prohibited ones. Several racemic piperidine-2,6-dione analogues [aminoglutethimide, p-nitro-glutethimide, p-nitro-5-aminoglutethimide, cyclohexylaminoglutethimide, phenglutarimide and thalidomide] have been resolved on Chiralpak IA and Chiralpak IB columns (25 cm × 0.46 cm). The non-conventional mobile phases used were methyl-tert-butyl ether-THF (90:10, v/v) [I], 100% dichloromethane [II] and 100% acetonitrile [III] separately at a flow rate of 1.0 mL/min using a UV detector at 254 nm. The resolution factors for Chiralpak IA and Chiralpak IB columns were 1.00–5.33 and 0.33–0.67, respectively. Chiralpak IA column gave better results than Chiralpak IB column for the reported molecules using the developed HPLC conditions. Experimental conditions and the possible chiral recognition mechanisms have been discussed.