182925-05-9

Upstream product

• 182925-04-8 p-nitrophenyl O-(6-O-acetyl-β-D-galactopyranosyl)-(1->4)-β-D-xylopyranoside 
• 3150-24-1 4-nitrophenyl-β-D-galactopyranoside 
• 2021-62-7 β-D-galactopyranosyl fluoride 
• 3068-32-4 1-bromo-2,3,4,6-tetra-O-acetyl-D-galactopyranose 
• 25878-60-8 D-galactose pentaacetate 
• 144683-70-5 p-nitrophenyl O-β-D-galactopyranosyl-(1->4)-β-D-xylopyranoside 
• 2001-96-9 p-nitrophenyl β-D-xylopyranoside 
• 4163-45-5 2,3,4,6-tetra-O-acetyl-β-galactopyranosyl fluoride 

Downstream Products

• 359689-81-9 p-nitrophenyl O-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl)-(1->3)-O-(2,4,6-tri-O-acetyl-β-D-galactopyranosyl)-(1->4)-2,3-di-O-acetyl-β-D-xylopyranoside 

Relevant academic research and scientific papers

Chemoenzymatic synthesis of a trisaccharide-serine conjugate, gal(β1-3)gal(β1-4)xyl(β1-o)-l-ser, use of galactosyl fluoride as a donor for transglycosylation

The trisaccharide - serine conjugate [Gal(β1-3)Gal(β1-4)Xyl(β-Ser], constituting the linkage region between the glycosaminoglycan and protein in proteoglycan, was synthesized by using enzymatic transglycosylation with a β-D-galactosidase as a key reaction. The yields of transglycosylation were much improved by using galactosyl fluoride as a donor in comparison with those obtained by a conventional p-nitrophenyl (PNP) galactoside. After enzymatic synthesis of Gal(β1-3)Gal(β1-4)Xyl(β)-PNP, cleavage of the PNP group of the fully acetylated trisaccharide, chemical coupling with serine, and final deprotection afforded Gal(β1-3)Gal(β1-4)Xyl(β)-Ser.

Chemoenzymatic synthesis of Gal(β1-3)Gal(β1-4)Xyl(β)-L-Ser and Gal(β1-3)Gal(β1-4)Xyl(β)-MU by the use of β-D-galactosidase

The title trisaccharide-serine conjugate 1 constituting the linkage region between glycosaminoglycan and protein in proteoglycan, was synthesized via a trisaccharide p-nitrophenyl (PNP) glycoside prepared by stepwise enzymatic transglycosidation to Xyl-PNP with a β-D-galactosidase. In the second transglycosidation step, partial protection of the disaccharide intermediate, Gal-Xyl-PNP, furnished selective galactosylation at the 3'-position. Cleavage of the PNP group after peracetylation, chemical coupling with serine and final deprotection afforded 1. Fluorescence labeled trisaccharide, Gal(β1-3)Gal(β1-4)Xyl(β)-MU (MU: 4-methylumbelliferyl) (2) was also synthesized in a simalar way.