DIRECT HPLC SEPARATION OF ENANTIOMERS OF MAIN MOGUISTEINE METABOLITE - COMPARISON OF DIFFERENT STATIONARY PHASES

Moguisteine is a new non-narcotic antitussive agent. The molecule cont ains a chiral centre, which is maintained in the metabolite structure. The unchanged drug is not found in the plasma of treated animals or h umans. The main moguisteine metabolite, MI, is the free racemic acid g enerated by hydrolysis of the ethyl-ester group of moguisteine. HPLC s eparation of MI enantiomers was attempted using various chiral station ary phases. Separation of the enantiomers was achieved with alpha-1-AG P and beta-cyclodextrin columns, which showed similar enantioselectivi ty and good resolution. However, the routine application of alpha-1-AG P columns turned out to be difficult, due to the limiting low flow rat e which displayed baseline problems and progressive loss of resolution . Beta-Cyclodextrin columns showed greater efficiency than alpha-1-AGP columns, as the former allows reproducible separation and can easily be applied to biological sample analysis in pharmacokinetic studies.