“…A third example is the one-pot enzymatic synthesis of Neu5Ac(a24)Gal(~l-4)GlcNAc (and analogues) based on a P-galactosidase-catalyzed galactosylation, using lactose as a donor and GlcNAc as an acceptor, and a pig liver a-2,6-sialyltransferase-catalyzed sialylation with in situ regeneration of CMP-NeuSAc [542]. A fourth example is the enzymatic synthesis of NeuSAc(a24)Gal(fi 14)GlcNAc(fi l-O)pent-4-ene, a precursor for the organic chemical synthesis of higher oligosaccharides [472]. The trisaccharide was synthesized starting from GlcNAc(fi l-O)pent-4-ene, UDP-Gal (in situ generated from UDP-Glc catalyzed by UDP-Gal 4-epimerase), and NeuSAc in a one-pot reaction employing fi-1,4-galactosyltransferase and a-2,6-sialyltransferase in a complete cofactor regeneration system.…”