Enzymatic derivatization of saccharides and their chemical polymerization

The enzymatic synthesis of sugar-based acetylene and ethylene derivatives as precursors to hydrophilic polymers is described. Propargyl and allyl alcohols have been used as glycosyl acceptors in the transglycosylation reactions of glycosidases with various disaccharides including lactose, maltose, and cellobiose. Reaction of propargyl and allyl alcohols with lactose catalyzed by β-galactosidase resulted in the formation of propargyl-β-D-galactopyranoside and allyl-β-D-galactopyranoside in 42 and 13% yields, respectively. Polymerization of propargyl-β-D-galactopyranoside with AlBr₃ in ethanol resulted in the formation of oligomeric poly(acetylenic) species (M_w = 1,300). Free radical polymerization of allyl-β-D-galactopyranoside in DMF or water resulted in poly(ethylenic) species with M_w > 30,000. The combined enzymatic and chemical reactions inherent in these syntheses provide a unique approach in the preparation of hydrophilic polymers containing sugars and their derivatives.