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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]

The zinc-induced reductive elimination from 5-deoxy-5-iodo derivatives of D-xylose and L-arabinose is carried out in order to study the structural parameters and the presence of [Zn.sup.2+] ions. The complexes between zinc and [Zn.sup.2+] bound carbohydrates are characterized with large stabilization energies, indicating that [Zn.sup.2+] might increase the affinity of the organic compound with the zinc metal surface.

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]

A simple method was developed for the direct formation of unsaturated iminosugars starting from readily available [omega]-methanesulfonylglycononitriles. The nucleophilic addition/cyclization reaction with variation of the Grignard reagent allows for a range of different side chains to be incorporated to generate libraries of broussonetine analogues.

The scope and limitation of highly diastereoselective nucleophilic mono(trifluoromethylation) of a tartaric acid-based diketone reaction was studied by using trifluoromethyl(trimethyl)silane. The process was found to be an interesting way to convert one natural chiral raw material into two functionalized enantiopure building blocks including a trifluoromethyl one.

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]

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]

Direct and efficient preparation of pentyl and octyl β-d-xylosides and oligoxylosides has been achieved from xylans and n-pentanol or n-octanol in aqueous medium with xylanases. The method has been successfully applied with xylooligosaccharides produced from hydrothermally pretreated wheat bran to produce octyl oligoxylosides. The pentose-based surfactants thus obtained exhibit good surface properties compared to other alkyl glycosides. These molecules represent interesting candidates for the production of new green surfactants. [ABSTRACT FROM AUTHOR]

Abstract: Domino reactions involving metal–halogen exchange, furanose ring-opening and nucleophilic addition from 3-O-benzyl-5-deoxy-5-iodo-1,2-O-isopropylidene-α-d-xylofuranose and the epimeric l-arabino derivative with various organometallic reagents are reported. In anhydrous conditions, with a large excess of organolithium or Grignard reagents, vicinal diols are obtained with good yields and a fair diastereoselectivity. Interestingly, with α-trimethylsilyl organolithium reagents, the fragmentation of the furanose ring to the substituted pent-4-enal is followed by a Peterson olefination giving dienic compounds in a four-step one-pot process. [Copyright &y& Elsevier]