Ketorolac was resolved into each enantiomer by interesterification using lipase B from Candida antarctica. The acid reacted with various alcohols and the ester and acid were resolved up to > 99% e.e. when reacted with octanol, which was the best result. To increase reactivity and enantioselectivity, the experimental conditions were adjusted by varying temperature, solvent, alcohols and reaction time. (C) 2001 Published by Elsevier Science Ltd.