Study of mechanism of enantioseparation. III. The influence of carbohydrate moieties of teicoplanin-bonded chiral stationary phase on the separation of some derivates of phenylcarbamic acid

摘要

Enantiomeric separation of alkoxysubstituted esters of phenylcarbamic acid (local anesthetic drugs) is carried out using high performance liquid chromatography (HPLC) with two chiral stationary phases. The teicoplanin chiral stationary phase - chirobiotic T and the teicoplanin chiral stationary phase without the pendant carbohydrate moieties - chirobiotic teicoplanin aglycone (TAG) were used. The influence of the sugar units, the concentration of the ionic modifiers (diethylamine), the influence of the position and of number of carbon atoms in the analytic alkoxychain substituent, and the composition of the mobile phase; on retention factors and resolution of enantiomers were investigated. By comparison of chromatographic parameters obtained by using both chiral stationary phases, the influence of carbohydrate moieties on the mechanism of chiral separation could be evaluated. The interaction mechanism of the enantiomeric separations is discussed. Better separation, in terms of - greater values of Rij of enantiomers - was achieved with the chirobiotic TAG column.