136198-40-8Relevant academic research and scientific papers
Kinetic Control of Regioselectivity in Glycosidase-catalysed Disaccharide Synthesis: Preparation of 2-Acetamido-4-O-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-2-deoxy-D-glucopyranose (N,N'-diacetylchitobiose) and 2-Acetamido-6-O-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-2-deoxy-D-gluco...
Singh, Suddham,Packwood, John,Crout, David H. G.
, p. 2227 - 2228 (1994)
During transfer of the N-acetyl-β-D-glucosaminyl (2-acetamido-2-deoxy-β-D-glucopyranosyl)residue from p-nitrophenyl N-acetyl-β-D-glucosaminide (p-nitrophenyl N-2-acetamido-2-deoxy-β-D-glucopyranoside) on to N-acetyl-D-glucosamine (2-acetamido-2-deoxy-D-glucopyranose) catalysed by the N-acetylhexosaminidase from Aspergillus oryzae, the major isomer formed was found to depend on the time course of the reaction, 1 -> 4 transfer predominating while the p-nitrophenyl glycoside was available as donor, but 1 -> 6 transfer when the initially-formed 1 -> 4 product took over as donor, results that could be interpreted in terms of a constant regioselectivity modulated by selective hydrolysis of the products.
COMBINATORIAL LIBRARIES
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Paragraph 171; 172; 173, (2015/11/02)
Synthetic mixtures comprising two or more synthetic oligoglucosamine based derivatives have been found to be useful in agricultural compositions for promoting seed germination. The disclosed synthetic mixtures may be applied to plant propagating materials, including seeds and other regenerable plant parts, including cuttings, bulbs, rhizomes and tubers. They may also be applied to foliage, or soil either prior to or following planting of plant propagating materials. Such applications may be made alone or in combination with fungicides, insecticides, nematicides and other agricultural agents used to improve plant growth and crop yield.
Combining weak affinity chromatography, NMR spectroscopy and molecular simulations in carbohydrate-lysozyme interaction studies
Landstroem, Jens,Bergstroem, Maria,Hamark, Christoffer,Ohlson, Sten,Widmalm, Goeran
supporting information; experimental part, p. 3019 - 3032 (2012/05/07)
By examining the interactions between the protein hen egg-white lysozyme (HEWL) and commercially available and chemically synthesized carbohydrate ligands using a combination of weak affinity chromatography (WAC), NMR spectroscopy and molecular simulations, we report on new affinity data as well as a detailed binding model for the HEWL protein. The equilibrium dissociation constants of the ligands were obtained by WAC but also by NMR spectroscopy, which agreed well. The structures of two HEWL-disaccharide complexes in solution were deduced by NMR spectroscopy using 1H saturation transfer difference (STD) effects and transferred 1H,1H-NOESY experiments, relaxation-matrix calculations, molecular docking and molecular dynamics simulations. In solution the two disaccharides β-d-Galp-(1→4) -β-d-GlcpNAc-OMe and β-d-GlcpNAc-(1→4)-β-d-GlcpNAc-OMe bind to the B and C sites of HEWL in a syn-conformation at the glycosidic linkage between the two sugar residues. Intermolecular hydrogen bonding and CH/π-interactions form the basis of the protein-ligand complexes in a way characteristic of carbohydrate-protein interactions. Molecular dynamics simulations with explicit water molecules of both the apo-form of the protein and a ligand-protein complex showed structural change compared to a crystal structure of the protein. The flexibility of HEWL as indicated by a residue-based root-mean-square deviation analysis indicated similarities overall, with some residue specific differences, inter alia, for Arg61 that is situated prior to a flexible loop. The Arg61 flexibility was notably larger in the ligand-complexed form of HEWL. N,N′-Diacetylchitobiose has previously been observed to bind to HEWL at the B and C sites in water solution based on 1H NMR chemical shift changes in the protein whereas the disaccharide binds at either the B and C sites or the C and D sites in different crystal complexes. The present study thus highlights that protein-ligand complexes may vary notably between the solution and solid states, underscoring the importance of targeting the pertinent binding site(s) for inhibition of protein activity and the advantages of combining different techniques in a screening process. The Royal Society of Chemistry 2012.
Protecting group free glycosidations using p-toluenesulfonohydrazide donors
Gudmundsdottir, Anna V.,Nitz, Mark
supporting information; scheme or table, p. 3461 - 3463 (2009/04/16)
(Figure Presented) N-Glycopyranosylsulfonohydrazides are introduced as glycosyl donors for protecting group free synthesis of O-glycosides, glycosyl azides, and oxazolines. Mono- and disaccharides containing a reducing terminal N-acelylglucosamine residue were condensed with p-toluenesulfonylhydrazide to give the desired β-D-pyranose donors. These donors can be activated with NBS and then glycosidated with the desired alcohol or transformed to the oxazoline or glycosyl azide.
Glycosidase-catalysed oligosaccharide synthesis: preparation of N-acetylchitooligosaccharides using the β-N-acetylhexosaminidase of Aspergillus oryzae
Singh, Suddham,Packwood, John,Samuel, Christopher J.,Critchley, P.,Crout, David H. G.
, p. 293 - 306 (2007/10/03)
The β-N-acetylhexosaminidase of Aspergillus oryzae catalyses the formation of 2-acetamido-4-O-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-2-deoxy-D-glucopyranose (di-N-acetylchitobiose) and 2-acetamido-6-O-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-2-deoxy-D-glucopyranose from p-nitrophenyl 2-acetamido-2-deoxy-β-D-glucopyranoside and 2-acetamido-2-deoxy-D-glucopyranose.The ratio of the two disaccharides is time-dependent.The ratio of (14)- to (16)-isomers is a maximum (ca. 9:1) at the point of disappearance of the glycosyl donor.If left to evolve, the ratio changes to 92:8 in favour of the (16)-isomer.Either the (14)- or the (16)-isomer can be isolated by treating the appropriately enriched disaccharide mixture with the β-N-acetylhexosaminidase of Jack bean (Canavalia ensiformis) or the β-N-acetylhexosaminidase of A. oryzae, respectively.Di-N-acetylchitobiose is an efficient donor of 2-acetamido-2-deoxy-D-glucopyranosyl units in reactions catalysed by the N-acetylhexosaminidase of A. oryzae.Di-N-acetylchitobiose itself acts as acceptor to give tri-N-acetylchitotriose .As the trisaccharide accumulates it, in turn, acts as acceptor giving tetra-N-acetylchitotetraose .The product mixture consisting of mono-, di-, tri-, and tetra-saccharides is conveniently separated by charcoal-Celite chromatography. Keywords: Glycosidase; N-acetylhexosaminidase; Chitooligosaccharides; Enzymatic synthesis.
Di and Tri saccharides, methods of making them and hair growth compositions containing them
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, (2008/06/13)
The preparation of a di or tri saccharide in which at least one glycoside residue bears an acetylamino substituent is catalysed enzymatically using an impure enzyme preparation with N-acetylhexosaminidase activity. The compounds produced, some of which are novel, may be useful to stimulate hair growth.
Biotransformation in Carbohydrate Synthesis. N-Acetylgalactosaminyl Transfer on to Methyl N-Acetyl-β-D-glucosaminide (Methyl 2-Acetamido-2-deoxy-β-D-glucopyranoside) and Methyl N-Acetyl-α-D-glucosaminide (Methyl 2-Acetamido-2-deoxy-α-D-glucopyranoside) Catalysed by a β-N-Acetylga...
Crout, David H.,Singh, Suddham,Swoboda, Ben E. P. G.,Critchley, Peter,Gibson, Walter T.
, p. 704 - 705 (2007/10/02)
Using a crude N-acetylgalactosaminidase from Aspergillus oryzae, the β-N-acetylgalactosaminyl moiety of p-nitrophenyl N-acetylgalactosaminide was transferred to the C-4 and C-6 hydroxy groups of methyl N-acetyl-β-D-glucosaminide and methyl N-acetyl-α-D-glucosaminide and, for the latter, with high efficiency and selectivity for transfer to the C-4 position.
Synthesis of peripheral trisaccharide sequence of lutropin, a pituitary glycoprotein hormone; use of chitobiose as a key starting material
Nishimura, Shin-Ichiro,Kuzuhara, Hiroyoshi
, p. 207 - 217 (2007/10/02)
A chitobiose derivative, methyl O-(3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranosyl)-(1->4)-3,6-di-O-acetyl-2-dexoy-2-phthalimido-β-D-glucopyranoside, was derived from the corresponding N-acetyl derivative and this was converted into the glycos
