Structure-Properties Relationship of Dimeric Surfactants from Butyl Glucosides

Carbohydrate containing dimeric surfactants were synthesized starting from Dglucose. Three different spacers were used to link the sugar moieties. The critical micelle concentration (CMC) for these new compounds was determined

Design and Synthesis of Hydrolytically Stable Multivalent Ligands Bearing Thiodigalactoside Analogues for Peanut Lectin and Human Galectin‑3 Binding

Herein, we describe the design and synthesis of a novel family of hydrolytically stable glycoclusters bearing thiodigalactoside (TDG) analogues as recognition elements of β-galactoside binding lectins. The TDG analogue was synthesized by thioglycosylation of a 6-<i>S</i>-acetyl-α-d-glucosyl bromide with the isothiouronium salt of 2,3,4,6-tetra-<i>O</i>-acetyl-β-d-galactose. Further propargylation of the TDG analogue allowed the coupling to azido-functionalized oligosaccharide scaffolds through copper­(I)-catalyzed azide–alkyne cycloaddition (CuAAC) under microwave activation. The final mono-, di-, and tetravalent ligands were resistant to enzymatic hydrolisis by Escherichia coli β-galactosidase. Binding affinities to peanut agglutinin and human galectin-3 were measured by isothermal titration calorimetry which showed <i>K</i>_a constants in the micromolar range as well as a multivalent effect. Monovalent ligand exhibited a binding affinity higher than that of thiodigalactoside. Docking studies performed with a model ligand on both β-galactoside binding lectins showed additional interactions between the triazole ring and lectin amino acid residues, suggesting a positive effect of this aromatic residue on the biological activity

O-Sulfated Derivatives of Glucuronic Acid

Abstract: 4-O-Substituted D-glucuronic acid derivatives were synthesized from D-glucose in order to study the regioselectivity of sulfation

Multivalent iminosugars to modulate affinity and selectivity for glycosidases.

International audienceA series of mono-, di- and tri-valent iminosugars based on oligoethylene scaffolds and N-substituted deoxynojirymicin epitopes have been synthesized by click chemistry to study the effect of multivalency on glycosidase inhibition. Biological evaluation evidenced differences in the inhibition trends as a function of the enzyme nature. The results demonstrate that multivalency can be used in some case to modulate both the affinity and the selectivity of glycosidase inhibition

Multivalent sialylation of beta-thio-glycoclusters by Trypanosoma cruzi trans sialidase and analysis by high performance anion exchange chromatography

International audienceThe synthesis of multivalent sialylated glycoclusters is herein addressed by a chemoenzymatic approach using the trans-sialidase of Trypanosoma cruzi (TcTS). Multivalent beta-thio-galactopyranosides and beta-thio-lactosides were used as acceptor substrates and 3'-sialyllactose as the sialic acid donor. High performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) was shown to be an excellent technique for the analysis of the reaction products. Different eluting conditions were optimized to allow the simultaneous resolution of the sialylated species, as well as their neutral precursors. The TcTS efficiently transferred sialyl residues to di, tri, tetra and octa beta-thio-galactosides. In the case of an octavalent thiolactoside, up to six polysialylated compounds could be resolved. Preparative sialylation reactions were performed using the tetravalent and octavalent acceptor substrates. The main sialylated derivatives could be unequivocally assigned by MALDI mass spectrometry. Inhibition of the transfer to the natural substrate, N-acetyllactosamine, was also studied. The octalactoside caused 82 % inhibition of sialic acid transfer when we used equimolar concentrations of donor, acceptor and inhibitor

Comité de rédaction

Comité de rédaction. In: Revue de géographie de Lyon, vol. 53, n°1, 1978. p. 2