A FACILE ENZYMATIC-SYNTHESIS OF CELLOOLIGOSACCHARIDE DERIVATIVES USING BETA-LACTOSYL FLUORIDE

A convenient method for the preparation of cellooligosaccharide deriva tives has been developed that uses beta-lactosyl fluoride as the glyco syl donor, The reaction consists of the following enzymatic processes; (1) a cellulase-catalyzed regio- and stereo-selective lactosylation o f a beta-cellobioside as the glycosyl acceptor, utilizing the transgly cosylating ability of an enzyme-substrate complex formed from beta-lac tosyl fluoride and cellulase; (2) beta-D-galactosidase-catalyzed regio selective cleavage of the terminal D-galactose unit from the lactosyla ted product, giving rise to a beta-cellotrioside derivative. A cellote traoside derivative has successfully been prepared in a stereo- and re gio-selective manner by repeating these enzymatic reactions and using the resulting beta-cellotrioside as starting material.