Optical resolution and enantiomeric purity determination of the analgesic cizolirtine

The optical resolution of (+/-)-cizolirtine was accomplished with excellent results (>99% ee) by means of crystallization with (+)- or (-)-di-p-toluoy ltartaric acid. The optical purity of the samples was controlled by three i ndependent methods: H-1 NMR, capillary electrophoresis (CE) (using beta-cyc lodextrins as chiral resolving agents), and HPLC (using a glycoproteic colu mn). The use of a rapid analytical technique like H-1 NMR for estimating th e relative amounts of each enantiomer, together with the high sensitivity o f CE, afforded a convenient strategy for monitoring the entire process lead ing to enantiopure compounds. Chirality 11:63-69, 1999. (C) 1999 Wiley-Liss , Inc.