Enzymatic synthesis of iso-globotriose from partially protected lactose☆

Abstract 6′- O -Acyl-lactose derivatives ( 1b-d ) were prepared by selective enzymatic acylation of lactose using the protease subtilisin. These compounds were used as acceptors for enzymatic transglycosylations catalysed by an α-galactosidase from Talaromyces flavus forming (after deacylation) iso -globotriose (α- d -Gal p -(1→3)-β- d -Gal p -(1→4)Glc, 2a ).