182925-07-1

Upstream product

• 182925-06-0 Acetic acid (2S,3R,4S,5S,6R)-5-acetoxy-6-acetoxymethyl-2-((3R,4S,5R,6R)-4,5-diacetoxy-6-hydroxy-tetrahydro-pyran-3-yloxy)-4-((2S,3R,4S,5S,6R)-3,4,5-triacetoxy-6-acetoxymethyl-tetrahydro-pyran-2-yloxy)-tetrahydro-pyran-3-yl ester 
• 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 
• 21209-51-8 N-benzyloxycarbonyl-L-serine benzyl ester 
• 249928-97-0 Acetic acid (2S,3R,4S,5S,6R)-5-acetoxy-6-acetoxymethyl-2-[(3R,4S,5R,6S)-4,5-diacetoxy-6-(3-nitro-pyridin-2-yloxy)-tetrahydro-pyran-3-yloxy]-4-((2S,3R,4S,5S,6R)-3,4,5-triacetoxy-6-acetoxymethyl-tetrahydro-pyran-2-yloxy)-tetrahydro-pyran-3-yl ester 
• 1010795-04-6 C₃₇H₄₈Cl₃NO₂₄ 

Relevant academic research and scientific papers

3-Nitro-2-pyridyl glycoside as donor for chemical glycosylation and its application to chemoenzymatic synthesis of oligosaccharide

3-Nitro-2-pyridyl (3NPy) glycosides, which act as versatile glycosyl donors in enzymatic transglycosylation, can also be chemically activated. Chemical glycosylation with protected 3NPy glycosides was readily effected at -20°C by using TMSOTf as a catalyst to afford the desired glycosides in good yields. A trisaccharide serine conjugate Gal(β1-3)Gal(β1-4)Xylβ-Ser was synthesized by combined use of enzymatic and chemical glycosylations. The trisaccharide 3NPy glycoside was prepared by stepwise transglycosylation of a Gal-3NPy donor to a Xyl-3NPy acceptor by using a β-galactosidase. After protection of the free hydroxy groups of the trisaccharide by acetylation, the 3NPy glycoside was then subjected to chemical glycosylation of a serine residue to afford the trisaccharide serine conjugate.

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.