ENANTIOMERIC SEPARATION OF BASIC DRUGS USING N-BENZYLOXYCARBONYLGLYCLYL-L-PROLINE AS COUNTER ION IN METHANOL

Direct separation of enantiomeric amines using mainly N-benzyloxycarbo nylglycyl-L-proline (L-ZGP) but also N-benzyloxycarbonylglyclglycl-L-p roline (L-ZGGP) as the chiral counter ion in methanol is described. Th e solid phase was Hypercarb porous graphitic carbon. Several amines of pharmacological interest (e.g., alprenolol, sotalol, terbutaline, pro methazine and trimipramine) were separated with high enantioselectivit y (alpha = 1.16-1.98) using L-ZGP and L-ZGGP as chiral selectors. In a ccordance with ion-pair chromatography, the retention of the enantiome ric amines was found to increase with increasing concentration of the anionic form of L-ZGP. Addition of a base (sodium hydroxide or an alky lamine) in excess of L-ZGP gave rise to a decrease in retention and en antioselectivity. The enantioselective retention was also affected by adding 2-propanol or acetonitrile to the mobile phase.