•A series of new glycoclusters modified by potentially anti-oxidant activity pharmacophores were synthesized.•The anti-adhesion activities of these compounds were assessed by a static state cell-based assay.•The results showed that decoration of glycoclusters might enhance the anti-adhesion activities.According to our early researches, some glycoclusters having glucose, mannose, cellose and lactose residues showed good anti-adhesion activity of leukocytes to endothelial cells and exerted anti-inflammatory effects. Based on these results and combination principles of drugs, a series of new glycoclusters modifying with potentially anti-oxidant activity pharmacophores have been synthesized, and their anti-adhesion activities were assessed by static state cell-based adhesion assay. The results showed that some modified glycoclusters displayed better activities than their leading compound.Download high-res image (208KB)Download full-size image

•A series of non-β-glucan glycoclusters can bind to dectin-1.•The strongest affinity property (KD) was 1.6 µM.•There may be a new carbohydrate binding site on dectin-1.Dectin-1, which specifically recognizes β-(1,3)-glucans, plays an important role in innate immune responses. For the first time, in this study we found that a series of non-β-glucan glycoclusters can bind to dectin-1 by means of surface plasmon resonance (SPR) assay. Hexavalent lactoside Ju-6 showed the strongest affinity property (KD = 1.6 µM). Interestingly, a continuous binding–dissociation experiment on SPR showed that Ju-6 and Laminarin binding to dectin-1 are independent of each other. Moreover, RT-PCR assay showed that Ju-6 cannot up-regulate cytokine gene expression or inhibit the promoting effect caused by Zymosan (a long-chain β-glucan). These results indicated that there might be a possible new carbohydrate binding site on dectin-1.

•A new series of homoglycoclusters and heteroglycoclusters were synthesized.•The anti-adhesion activities of these compounds were assessed by SPR and a static state cell-based assay.•These results did not show significant difference of anti-adhesion activities between flexible scaffold and rigid scaffold.A new series of mixed-type heteroglycoclusters containing mannose and lactose were synthesized. In the synthesis of rigid scaffold of heteroglycocluster, we found that trans-isomer could be prepared stereoselectively by means of Grubbs olefin cross-metathesis reactions. Moreover, sequential acylation using cyclic anhydride as scaffold could give cis-isomer. These two methods may provide complementarity of stereochemistry in heteroglycocluster assembling. The anti-adhesion activities of these compounds were assessed by Surface Plasmon Resonance (SPR) and static state cell-based adhesion assay. These results indicated that the rigid scaffold might not affect the anti-adhesion activities.

We report here the syntheses of mono- to tetravalent glycoclusters containing 1-methylene-C-β-lactose. The 1-methylene-C-β-lactose moiety has been synthesized from octa-acetyl-β-lactose using the key carbonyl insertion reaction and linked to a series of alkynlated scaffolds via CuAAC reaction to afford mono- to tetravalent glycoclusters. The binding affinities of the final products to galectin-3 were found in the range of 10–100 μM.

We utilized the glycosyl acceptor tagging method with ionic liquid support for synthesis of the core segment of Clostridium botulinum C2 toxin ligand through a divergent synthetic strategy without chromatographic purification. The total yield was 57.1% and the reaction was completed in 10 h. The efficient ionic liquid supported glycosylation and purification procedure was applied for the synthesis of branched glucosamine-containing oligosaccharides for the first time, which expanded the scope of ionic liquid supported synthesis of biologically important oligosaccharides.The core segment of Clostridium botulinum C2 toxin ligand was synthesized in 57.1% yield with the glycosyl acceptor tagged on an ionic liquid support through a divergent synthetic strategy without chromatographic purification. The efficient ionic liquid supported glycosylation and purification procedure was applied for the synthesis of branched glucosamine-containing oligosaccharides for the first time, which expanded the scope of ionic liquid supported synthesis of biologically important oligosaccharides.

We report here the syntheses of mono- to tetravalent glycoclusters containing 1-methylene-C-β-lactose. The 1-methylene-C-β-lactose moiety has been synthesized from octa-acetyl-β-lactose using the key carbonyl insertion reaction and linked to a series of alkynlated scaffolds via CuAAC reaction to afford mono- to tetravalent glycoclusters. The binding affinities of the final products to galectin-3 were found in the range of 10–100 μM.