60280-57-1Relevant academic research and scientific papers
Syntheses of mucin-type O-glycopeptides and oligosaccharides using transglycosylation and reverse-hydrolysis activities of Bifidobacterium endo-α-N-acetylgalactosaminidase
Ashida, Hisashi,Ozawa, Hayato,Fujita, Kiyotaka,Suzuki, Shun'Ichi,Yamamoto, Kenji
experimental part, p. 125 - 132 (2011/10/09)
Endo-α-N-acetylgalactosaminidase catalyzes the release of Galβ1-3GalNAc from the core 1-type O-glycan (Galβ1-3GalNAcα1- Ser/Thr) of mucin glycoproteins and synthetic p-nitrophenyl (pNP) α-linked substrates. Here, we report the enzymatic syntheses of core 1 disaccharide-containing glycopeptides using the transglycosylation activity of endo-α-N-acetylgalactosaminidase (EngBF) from Bifidobacterium longum. The enzyme directly transferred Galβ1-3GalNAc to serine or threonine residues of bioactive peptides such as PAMP-12, bradykinin, peptide-T and MUC1a when Galβ1-3GalNAcα1-pNP was used as a donor substrate. The enzyme was also found to catalyze the reverse-hydrolysis reaction. EngBF synthesized the core 1 disaccharide-containing oligosaccharides when the enzyme was incubated with either glucose or lactose and Galβ1-3GalNAc prepared from porcine gastric mucin using bifidobacterial cells expressing endo-α-N- acetylgalactosaminidase. Synthesized oligosaccharides are promising prebiotics for bifidobacteria.
Cyclic di-t-butylsilylenediyl ether group as a convenient protective group for the glycoconjugate synthesis
Kumagai, Daijyu,Miyazaki, Masaki,Nishimura, Shin-Ichiro
, p. 1953 - 1956 (2007/10/03)
Treatment of methyl β-D-glucopyranoside, methyl α-D-glucopyranoside, 2-azido-2-deoxy-β-D-galactopyranosyl fluoride, and 1,6-anhydro-β-lactose with di-t-butyldichlorosilane gave the corresponding 4,6-cyclic di-t-butylsilylenediyl ether (4,6-CDBS) derivatives in high yields. It was suggested that the 4,6-CDBS group is quite stable under general conditions for further chemical manipulations such as the acetylation, benzylation and glycosylation reactions employed widely in the carbohydrate chemistry. This protective group was readily removed by treatment with tetrabutylammonium fluoride or triethylamine-3HF complex under mild conditions.
Chemoenzymatic synthesis of the Thomsen-Friedenreich antigen determinant
Gambert, Ulrike,Thiem, Joachim
, p. 85 - 89 (2007/10/03)
The efficient chemoenzymatic synthesis of the Thomsen-Friedenreich antigen determinant is demonstrated under transglycosylation conditions employing β-galactosidase from bovine testes.
βGal(1-3)GalNAc block donor for the synthesis of TF and α sialyl(2-6)TF as glycopeptide building blocks
Qiu, Dongxu,Gandhi, Sham S.,Koganty, R. Rao
, p. 595 - 598 (2007/10/02)
4,6-Benzylidene protected N-acetylgalactosamine β-glycosylated at the 3-position with peracetylated galactose is found to be an excellent donor for the synthesis of Thomsen-Freidenreich (TF) family of antigens. These may serve further as building blocks f
APPLICATION OF THE TRICHLOROACETIMIDATE METHOD TO THE SYNTHESIS OF GLYCOPEPTIDES OF THE MUCIN TYPE CONTAINING A β-D-Galp-(1->3)-D-GalpNAc UNIT
Kinzy, Willy,Schmidt, Richard R.
, p. 265 - 276 (2007/10/02)
Mucin-type O-glycopeptides containig the β-D-Galp-(1->3)-D-GalpNAc disaccharide core unit, which is also the T-antigenic determinant, were synthesized from D-galactose, 2-azido-2-deoxy-D-galactose, 2-azido-2-deoxylactose, and L-serine precursors by applying the trichloroacetimidate method.Thus, β-D-Galp-(1->3)-α-D-GalpNAc-(1->3)-Ser (1) and β-D-Galp-(1->4)-β-D-GlcpNAc-(1->6)-3)>-α-D-GalpNAc-(1->3)-Ser (2) were obtained.A protected precursor of 2 having free OH groups at C-4 and C-6 of the inner sugar unit is a valuable intermediate for the synthesis of further O-glycopeptides of this core-unit type.
BLOCKSYNTHESE VON O-GLYCOPEPTIDEN UND ANDEREN T-ANTIGEN STRUKTUREN
Paulsen, Hans,Paal, Michael
, p. 71 - 84 (2007/10/02)
Under the conditions of in situ anomerisation, the 2-azido-4,6-di-O-benzoyl-2-deoxy-3-O-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl)-α-D-galactopyranosyl bromide reacted directly and with high selectivity with the reactive hydroxyl groups of L-serine and L-threonine derivatives to form α-glycosidically-linked products.Thus, the glycopeptides containing L-serine and L-threonine are more accessible.The disaccharide block could also be coupled with other reactive hydroxyl compounds to give compounds that contain the T-receptor.
Synthesis of the glycopeptide O-beta-D-galactopyranosyl-(1 to 3)-O-(2-acetamido-2-desoxy-alpha-D-galactopyranosyl)-(1 to 3)-L-serine and -L-threonine
Paulsen,Hoelck
, p. 89 - 107 (2007/10/02)
In the presence of silver carbonate-silver perchlorate and dichloromethane-toluene as solvent, 3,4,6-tri-O-acetyl-2-azido-2-deoxy-beta-D-galactopyranosyl chloride, and derivatives of L-serine and -L-serine and -L-threonine, gave, with high stereoselectivity, the benzyl esters of N-(benzyloxycarbonyl)-3-O-(3,4,6-tri-O-acetyl-2-azido-2-deoxy-alpha-D-galactopyranosyl)-L-serine (7) and -L-threonine (22), which were hydrogenolyzed and deblocked to give 3-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyl)-L-serine and -L-threonine, respectively, corresponding to the hapten of the Tn-antigen. Reduction of the azido group of 7, followed by selective O-deacetylation and benzylidenation, gave a derivative that was glycosylated with 2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl bromide to yield a disaccharide. A similar sequence of reactions, starting from 22, gave the L-threonine analog. Removal of the protecting groups from both compounds afforded O-beta-D-galactopyranosyl-(1 to 3)-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyl)-L-serine and -L-serine and -L-threonine, respectively, the hapten of the T-antigen.
