Chiral resolution of diols by capillary electrophoresis using borate-cyclodextrin complexation

In this study, the chiral separation of compounds with a cis-diol structure using an electrolyte containing borate and cyclodextrin (CD) is described. A dual mechanism involving both inclusion of the aromatic moiety into the cavity of the CD and the formation of mixed borate complexes is assumed to be responsible for chiral recognition. It has been shown that the separation is greatly influenced by the structure of the CD, the pH and the concentration of both the CD and borate. The method was optimized with some simple diol compounds and applied to quinazoline-(3H,1H)-4-on-2-thiones and tetrazol-5-thiones of potential pharmaceutical interest.