PRODUCTION OF GLUCOSAMINE CONTAINING DISACCHARIDES OF THE LEWIS-A ANDLEWIS-X TYPES EMPLOYING GLYCOSIDASES

Disaccharide derivatives of interest for inhibition studies and for sy nthesis of the blood group determinants Lewis-a and Lewis-x were obtai ned with glycosidases as catalysts. Thus, Fuc alpha(1-4)(6-OBn)GlcNH(2 ) beta SEt and Gal beta 1-3(6-OBn)GlcNH(2) beta-SEt were produced empl oying (6-OBn)GlcNH(2) beta SEt as acceptor and alpha-L-fucosidase and beta-D-galactosidase, respectively, as catalysts. The phthalimido deri vative of lactosamine, Gal beta 1-4GlcNPhth beta SEt, was prepared fro m lactose employing GlcNPhth beta SEt as the acceptor and a yeast beta -galactosidase as catalyst. The reactions were both regio- and stereos pecific, which allowed straightforward production of pure products on a g scale and higher.