173468-35-4

Upstream product

• 173468-29-6 4-nitrophenyl O-β-D-xylopyranosyl-(1<*>4)-O-β-D-xylopyranosyl-(1<*>4)-β-D-xylopyranoside 
• 2001-96-9 p-nitrophenyl β-D-xylopyranoside 
• 100-02-7 4-nitro-phenol 
• 879367-03-0 β-D-xylopyranosyl-(1→4)-α-D-xylopyranosyl fluoride 
• 6819-07-4 p-nitrophenyl β-D-xylopyranosyl-(1->4)-β-D-xylopyranoside 
• 139307-05-4 xylotetraose 
• 24624-78-0 1-O-(4-nitrophenyl)-2,3,4-tri-O-acetyl-β-D-xylopyranoside 
• 3068-31-3 1-bromo-2,3,4-tri-O-acetyl-α-D-xylopyranose 
• 35395-98-3 O-(2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-(1<*>4)-O-(2,3-di-O-acetyl-β-D-xylopyranosyl)-(1<*>4)-1,2,3-tri-O-acetyl-β-D-xylopyranose 
• 173468-23-0 methyl O-(2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-(1<*>4)-O-(2,3-di-O-acetyl-β-D-xylopyranosyl)-(1<*>4)-2,3-di-O-acetyl-1-thio-β-D-xylopyranoside 
• 173468-11-6 4-nitrophenyl 2,3-di-O-benzoyl-4-O-chloroacetyl-β-D-xylopyranoside 
• 173468-12-7 4-nitrophenyl 2,3-di-O-benzoyl-β-D-xylopyranoside 
• 173468-09-2 4-nitrophenyl 4-O-chloroacetyl-β-D-xylopyranoside 
• 173468-31-0 4-nitrophenyl O-(2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-(1<*>4)-bis4)>-2,3-di-O-benzoyl-β-D-xylopyranoside 

Relevant academic research and scientific papers

Novel substrates for the automated and manual assay of endo-1,4-β-xylanase

endo-1,4-β-Xylanase (EC 3.2.1.8) is employed across a broad range of industries including animal feed, brewing, baking, biofuels, detergents and pulp (paper). Despite its importance, a rapid, reliable, reproducible, automatable assay for this enzyme that is based on the use of a chemically defined substrate has not been described to date. Reported herein is a new enzyme coupled assay procedure, termed the XylX6 assay, that employs a novel substrate, namely 4,6-O-(3-ketobutylidene)-4-nitrophenyl-β-45-O-glucosyl-xylopentaoside. The development of the substrate and associated assay is discussed here and the relationship between the activity values obtained with the XylX6 assay versus traditional reducing sugar assays and its specificity and reproducibility were thoroughly investigated.

Glycosynthase-based synthesis of xylo-oligosaccharides using an engineered retaining xylanase from Cellulomonas fimi

Glycosynthases are synthetic enzymes derived from retaining glycosidases in which the catalytic nucleophile has been replaced. The mutation allows irreversible glycosylation of sugar acceptors using glycosyl fluoride donors to afford oligosaccharides with

Enzymatic synthesis of β-xylanase substrates: Transglycosylation reactions of the β-xylosidase from Aspergillus sp.

A β-D-xylosidase with molecular mass of 250±5 kDa consisting of two identical subunits was purified to homogeneity from a cultural filtrate of Aspergillus sp. The enzyme manifested high transglycosylation activity in transxylosylation with p-nitrophenyl β-D-xylopyranoside (PNP-X) as substrate, resulting in regio- and stereoselective synthesis of p-nitrophenyl (PNP) β-(1→4)-D-xylooligosaccharides with dp 2-7. All transfer products were isolated from the reaction mixtures by HPLC and their structures established by electrospray mass spectrometry and 1H and 13C NMR spectroscopy. The glycosides synthesised, β-Xyl-1→(4-β-Xyl-1→)n4-β-Xyl-OC 6H4NO2-p (n=1-5), were tested as chromogenic substrates for family 10 β-xylanase from Aspergillus orizae (XynA) and family 11 β-xylanase I from Trichoderma reesei (XynT) by reversed-phase HPLC and UV-spectroscopy techniques. The action pattern of XynA against the foregoing PNP β-(1→4)-D-xylooligosaccharides differed from that of XynT in that the latter released PNP mainly from short PNP xylosides (dp 2-3) while the former liberated PNP from the entire set of substrates synthesised.

Synthesis of 2- and 4-nitrophenyl β-glycosides of β-(1 → 4)-D-xylo-oligosaccharides of dp 2-4

2- and 4-Nitrophenyl β-D-xylopyranosides (4 and 5) were transformed, via dibutyltin oxide-mediated acylation, into the corresponding 2,3-di-O-benzoyl derivatives 11 and 15. Xylobiose and xylotriose were easily isolated by charcoal column chromatography from a commercially available material and converted into the di- and trisaccharide methyl 1-thio-β-glycosides 36 and 37. The 2- and 4-nitrophenyl β-glycosides of the β-(1 → 4)-D-xylo-oligosaccharides of dp 2-4 were synthesized by N-iodosuccinimide-silver triflate-promoted condensation using 11 and 15 as the glycosyl acceptors and ethyl 1-thio-β-D-xylopyranoside triacetate 16, 36, and 37 as the glycosyl donors. Also described are an improved preparation of 4 and 5, and the synthesis of 1-naphthyl β-D-xylopyranoside, as well as an alternative approach to the 2- and 4-nitrophenyl β-xylobiosides.