7234-31-3Relevant academic research and scientific papers
Selective demethylation ofO-aryl glycosides by iridium-catalyzed hydrosilylation
Jones, Caleb A. H.,Schley, Nathan D.
supporting information, p. 5953 - 5956 (2021/06/18)
The cleavage of alkyl ethers by hydrosilylation is a powerful synthetic tool for the generation of silyl ethers. Previous attempts to apply this transformation to carbohydrate derivatives have been constrained by poor selectivity and preferential reductio
A new look at acid catalyzed deacetylation of carbohydrates: A regioselective synthesis and reactivity of 2-O-acetyl aryl glycopyranosides
Stepanova, Elena V.,Nagornaya, Marina O.,Filimonov, Victor D.,Valiev, Rashid R.,Belyanin, Maxim L.,Drozdova, Anna K.,Cherepanov, Victor N.
, p. 60 - 66 (2018/02/20)
In the present work we report that acetyl groups of per – acetylated aryl glycosides have different reactivity during the acidic deacetylation using HCl/EtOH in CHCl3, which leads to preferential deacetylation at O-3, O-4 and O-6. Thereby, the one-step preparation of 2-O-acetyl aryl glycosides with simple aglycon was accomplished for the first time. It was proved that the found reagent is to be general and unique for the preparation of series of 2-О-acetyl aryl glycosides. We have determined the influence of both carbohydrate moiety and the aglycon on the selectivity of deacetylation reaction by kinetic experiments. Using DFT/B3LYP/6-31G(d,p) and semi-empirical АМ1 methods we have found that the highest activation barrier is for 2-О-acetyl group. This completely explains the least reactivity of 2-О-acetyl group.
Synthesis and structure of tricarbonyl(η6-arene)chromium complexes of phenyl and benzyl D-glycopyranosides
Ziegler, Thomas,Heber, Ulrich
supporting information; experimental part, p. 1059 - 1070 (2012/10/18)
A series of 15 glycoside-derived tricarbonyl(η6-arene) chromium complexes were prepared in 19-87% yield by heating fully acetylated or methylated aryl O-, S-, N- and C-glycosides of D-glucopyranose and D-mannopyranose with hexacarbonylchromium.
Purification, characterization, and gene identification of an α-glucosyl transfer enzyme, a novel type α-glucosidase from Xanthomonas campestris WU-9701
Sato, Toshiyuki,Hasegawa, Nobukazu,Saito, Jun,Umezawa, Satoru,Honda, Yuki,Kino, Kuniki,Kirimura, Kohtaro
body text, p. 20 - 27 (2012/09/05)
The α-glucosyl transfer enzyme (XgtA), a novel type α-glucosidase produced by Xanthomonas campestris WU-9701, was purified from the cell-free extract and characterized. The molecular weight of XgtA is estimated to be 57 kDa by SDS-PAGE and 60 kDa by gel filtration, indicating that XgtA is a monomeric enzyme. Kinetic properties of XgtA were determined for α-glucosyl transfer and maltose-hydrolyzing activities using maltose as the α-glucosyl donor, and if necessary, hydroquinone as the acceptor. The Vmax value for α-glucosyl transfer activity was 1.3 × 10-2 (mM/s); this value was 3.9-fold as much as that for maltose-hydrolyzing activity. XgtA neither produced maltooligosaccharides nor hydrolyzed sucrose. The gene encoding XgtA that contained a 1614-bp open reading frame was cloned, identified, and highly expressed in Escherichia coli JM109 as the host. Site-directed mutagenesis identified Asp201, Glu270, and Asp331 as the catalytic sites of XgtA, indicating that XgtA belongs to the glycoside hydrolase family 13.
CHELATION CONTROLLED REGIOSELECTIVE ALKYLATION AND 1,4 CHIRALITY TRANSFER IN OPTICALLY ACTIVE 1-ALKOXY-1,4-CYCLOHEXADIENES
Stanssens, Dirk,Keukeleire, Denis De,Vandewalle, Maurits
, p. 4195 - 4198 (2007/10/02)
Chelation controlled alkylation of optically active 1-alkoxy-1,4-cyclohexadienes leads to a mixture of 1,4-cyclohexadienes 4a-c and 1,3-cyclohexadienes 5a-c.The regio- and diastereoselectivities depend upon the nature of the chiral auxiliary and the react
