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Water‐soluble and air‐stable gold nanoparticles stabilized by a xyloside‐based ligand containing a pyridine ring‐functionalized 1,2,3‐triazole backbone were prepared in the presence of a reducing agent. During their preparation, UV‐vis and NMR spectroscopic techniques were used to study the interaction between the xyloside ligand and Au(III) ions. These AuNPs were characterized by UV‐vis spectroscopy, TEM and DLS and showed a small size (average diameter<10 nm determined by TEM). Their catalytic activity was tested in the reduction of 4‐nitrophenol (4‐NP) to 4‐aminophenol (4‐AP) in water. [ABSTRACT FROM AUTHOR]

A short and convenient approach to the original xyloside‐based ligands, has been achieved, using d‐xylose as a starting material. The complexation properties of these ligands towards Au(III) cations were studied by different methods, such as multinuclear NMR, mass spectrometry, elemental analysis. A preliminary study using protometric titrations has been carried out in aqueous solution under various pH conditions, thus in order to investigate the binding of Au(III) cations to these ligands. Furthermore, molecular calculations were performed to obtain additional structural information. The catalytic activity of the most stable Au(III) complexes was evaluated for the homogeneous reduction of 4‐nitrophenol (4‐NP) to 4‐aminophenol (4‐AP) in the presence of NaBH4. [ABSTRACT FROM AUTHOR]

A novel strategy for the synthesis of 2‐substituted thioglycals has been developed from a carbohydrate‐derived ketene dithioacetal in a two‐step sequence. The introduction of various electrophilic groups at the double bond of the ketene dithioacetal was achieved before the elimination of the thioalkyl group to yield 2‐substituted thioglycals. Removal of the exocyclic thioalkyl group was obtained by the selective formation of the exocyclic glycosyl sulfoxide followed by treatment by an organolithium reagent. The synthetic potential of these 2‐substituted thioglycals was illustrated by the alkylation at the sulfur atom leading to unsaturated carbohydrate‐derived sulfonium salts. [ABSTRACT FROM AUTHOR]

Front Cover: A Xyloside-Based Ligand to Stabilize Gold Nanoparticles: Preparation and Application (Eur. J. Inorg. Gold, nanoparticles, nitrophenol, triazole, xylose Keywords: Gold; nanoparticles; nitrophenol; triazole; xylose EN Gold nanoparticles nitrophenol triazole xylose 1 1 1 06/27/23 20230623 NES 230623 B The Front Cover b shows a gold nanoparticle decorated with a simple xyloside ligand having a 1,2,3-triazole backbone functionalized with a pyridine ring. [Extracted from the article]

Different mono-xylosides and their corresponding xylobiosides obtained by a chemo-enzymatic approach featuring various substituents attached to a triazole ring were probed as priming agents for glycosaminoglycan ( GAG) biosynthesis in the xylosyltransferase-deficient pgsA-745 Chinese hamster ovary cell line. Xylosides containing a hydrophobic aglycone moiety were the most efficient priming agents. Mono-xylosides induced higher GAG biosynthesis in comparison with their corresponding xylobiosides. The influence of the degree of polymerization of the carbohydrate part on the priming activity was investigated through different experiments. We demonstrated that in case of mono-xylosides, the cellular uptake as well as the affinity and the catalytic efficiency of β-1,4-galactosyltransferase 7 were higher than for xylobiosides. Altogether, these results indicate that hydrophobicity of the aglycone and degree of polymerization of glycone moiety were critical factors for an optimal priming activity for GAG biosynthesis. [ABSTRACT FROM AUTHOR]

Fucosidase inhibitors represent captivating targets for various biological applications. Iminosugars featuring a fluoroalkyl chain in the pseudoanomeric position were synthesized by nucleophilic addition of a perfluoroalkyl Grignard reagent to a nitrone. Reduction of the N-O bond of the hydroxylamine was achieved by treatment with an aqueous solution of sulfur dioxide. The p Ka = 4.5 of the target pyrrolidine reflected a strong electronic effect of the fluoroalkyl chain. Inhibitory potencies of the fluorinated iminosugars and their corresponding hydroxylamines were evaluated against α- L-fucosidase at various pH values. [ABSTRACT FROM AUTHOR]