35599-02-1Relevant articles and documents
Glycosynthase with broad substrate specificity-an efficient biocatalyst for the construction of oligosaccharide library
Wei, Jinhua,Lv, Xun,Lue, Yang,Yang, Gangzhu,Fu, Lifeng,Yang, Liu,Wang, Jianjun,Gao, Jianhui,Cheng, Shuihong,Duan, Qian,Jin, Cheng,Li, Xuebing
, p. 2414 - 2419 (2013/05/23)
A versatile glycosynthase (TnG-E338A) with strikingly broad substrate scope has been developed from Thermus nonproteolyticus β-glycosidase (TnG) by using site-directed mutagenesis. The practical utility of this biocatalyst has been demonstrated by the facile generation of a small library containing various oligosaccharides and a steroidal glycoside (total 25 compounds) in up to 100 % isolated yield. Moreover, an array of eight gluco-oligosaccharides has been readily synthesized by the enzyme in a one-pot, parallel reaction, which highlights its potential in the combinatorial construction of a carbohydrate library that will assist glycomic and glycotherapeutic research. Significantly, the enzyme provides a means by which glycosynthase technology may be extended to combinatorial chemistry.
Syntheses of p-nitrophenyl 3- and 4-thio-β-d-glycopyranosides
Chen, Hong-Ming,Withers, Stephen G.
experimental part, p. 2596 - 2604 (2011/01/12)
Thioglycosides have proved to be useful, enzymatically stable analogs of glycosides for structural and mechanistic studies and their synthesis is considerably simplified through the use of thioglycoligases. As part of an investigation into the use of thio
Carbohydrate-carbohydrate interactions in water with glycophanes as model systems
Morales, Juan Carlos,Zurita, Dacil,Penades, Soledad
, p. 9212 - 9222 (2007/10/03)
The synthesis and conformational properties of glycophanes 2 and 3 (cyclodextrin-cyclophane hybrid receptors containing two maltose units linked by (4-hydroxymethyl) benzoic acid spacer) are described. The binding properties in water of these receptors with a series of 4-nitrophenyl glycosides with α- and β-configurations at the anomeric center have been studied using 1H NMR spectroscopy and molecular mechanics calculations. A comparison of these properties with those of glycophane 1 (an α,α-trehalose containing glycophane) and α-cyclodextrin (αCD) using the same glycosides shows the existence of a stabilizing contribution to the free energy of binding in the case of of glycophanes but not in the case of the αCD system. This contribution is due to carbohydrate-carbohydrate interactions between both host and guest lipophilic sugar surfaces. Glycophanes 1, 2, and 3 show similar α/β selectivity on binding the ligands, despite the great flexibility of 3 related to 1 and 2. Parallels are drawn between the thermodynamic behavior of these model systems and that proposed for sugar- protein interactions.
Rates of Acidic and Alkaline Hydrolysis of Substituted Phenyl α- and βDMannopyranosides
Kyosaka, Shigehisa,Murata, Sanae,Tanaka, Mitsuya
, p. 3902 - 3905 (2007/10/02)
The rates of hydrolysis of substituted phenyl α- and β-D-mannopyranosides were measured in acidic and alkaline solutions.In 0.11 N hydrochloric acid solution, the α-mannosides were hydrolyzed faster than the corresponding β-anomers.The rates of hydrolysis for the α-mannosides were unaffected by substitution in the phenyl group (Hammett reaction constant ρ=-0.07+/-0.065 (S.D.)), and those for the β-mannosides were slightly enhanced by the introduction of electron-releasing substituents (ρ=-0.25+/-0.082).In sodium hydroxide solution, the α-mannosides liberated their aglycones, phenols, much faster than the corresponding β-anomers and the rates were enhanced by the introduction of electron-withdrawing substituents (ρ=+2.7+/-0.14 for the α-, +3.1+/-0.46 for the β-mannosides, each in 3.93 N NaOH).Phenyl α-mannoside was hydrolyzed much faster than phenyl β-glucoside, though both have trans-1,2 configuration, indicating the importance of a 1,2-diaxial orientation for the reaction. Keywords --- aryl α-mannopyranoside; aryl β-mannopyranoside; acid hydrolysis; alkaline hydrolysis; Hammett plot
