Abstract: A process for performing an enzyme-catalyzed reaction in a reaction mixture comprising two phases, a first aqueous phase containing an enzyme which is not accessible and a second substantially non-aqueous phase containing a non-water miscible solvent wherein a compound derived from fluorescein or a substituted fluorescein is present for the purpose of measuring aqueous pH by monitoring spectroscopic properties. Novel compounds derived from fluorescein or a substituted fluorescein which may be used in the process and a method for producing some of the novel compounds are also claimed.

Abstract: Organic compounds susceptible to hydrolysis are prepared by reaction in a water-immiscible organic liquid in contact with an enzyme activated with water to catalyze the reaction and desiccant means to lower the water activity of the dispersion from which the reaction products are recovered. The enzyme may be a lipase to catalyze an interesterification process and the desiccant means may be immersed in the dispersion to remove water in the liquid phase or in the headspace above the dispersion to remove water vapor.