Ergot alkaloids as chiral selectors in capillary electrophoresis and other electromigration methods

This review surveys the accomplishments in enantioseparations by capillary electrophoresis and other electromigration methods obtained using the semisynthetic ergot alkaloid derivative - terguride and its analogues as the chiral selectors. These selectors exhibited a marked discrimination towards carboxylic groups containing compounds under specific experimental conditions (BGE or buffer pH, % of organic modifier in the mobile phase) that enhanced stereoselective interactions of the selectant with basic functions of the ergoline skeleton. Substituents in N(1) and urea side chain of terguride affected the discriminative process. The versatility of terguride derivatives to be used as the chiral selectors was demonstrated in three different electromigration formats, i.e. dissolved in BGE in the partial filling – counter current mode, on continuous beds (polymethacrylate and sol-gel based monoliths) and in open-tubular format. These techniques were also used successfully for systematic studies on stereoselective biotrasformations of amino acids in biological fluids or herbicides in soil.