Fullerene sugar balls

Abstract

Fullerene hexakis-adducts bearing 12 peripheral carbohydrate moieties have been prepared by grafting sugar derivatives onto the fullerene core through the copper mediated Huisgen 1,3-dipolar cycloaddition of azides and alkynes.

Synthesis of giant globular multivalent glycofullerenes as potent inhibitors in a model of Ebola virus infection

“…Depending upon the starting sugar derivatives employed (monomer, dimer or trimer) 12, 24 and up to 36 monosaccharides have been introduced on the periphery of the fullerene central core in a straightforward manner. 14,15,16,17 Remarkably, some of the aforementioned glycofullerenes have proven to show interesting biomedical applications. 18 Thus, a significant multivalent effect has been observed in the inhibition profile of a [60]fullerene hexakis-adduct endowed with 12 iminosugar units towards different glycosidases.…”

“…12 We have recently developed a procedure based on a click-chemistry approach which provides hexakis-adducts with twelve alkyne or azide terminal groups in high yields from simple malonates. 13,14 These hexakis-adducts can be easily and efficiently functionalized by using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction allowing the introduction of twelve functional groups simultaneously in a regioselective and efficient way. Since these hexakis-adducts show an octahedral arrangement of equally separated addends located on the [60]fullerene periphery in a globular topology, they constitute a very attractive platform for the study of multivalent interactions with lectins, with important advantages such as the better biocompatibility of the carbon central core, the globular geometry of the functional groups and the ease and versatile chemical functionalization.…”

Glycodendritic structures: tools to interact with DC-SIGN

“…In all these cases, fullerene derivatives showed an amphiphilic character with the fullerene being the lipophilic part of the structures. Recently, it has been shown that this amphiphilic character of sugar fullerene conjugates can be avoided by obtaining hexakis-adducts of [60]fullerene in which the C60 sphere could be completely surrounded by the sugar moieties (mannose, glucose, galactose or fucose) in a T-symmetrical octahedral addition pattern (Nierengarten et al, 2010). The conjugation of sugar residues to an alkyne-substituted Bingel-Hirsch hexakis-adducts was performed by employing the CuACC methodology.…”

“…For this aim, a vast array of unnatural glycoconjugates (neoglycoconjugates) with different valencies and spatial arrangement of the ligand have been constructed as sugar binding proteins antagonist to prevent or treat diseases caused by pathogens . Scaffolds based on peptides and proteins (Davis, 2002;Payne, Wong, 2010;Westerlind, 2012), polymers (Miura, 2012;Eissa, Cameron, 2013), calixarenes (Baldini, et al, 2007;Dondoni, Marra, 2010), dendrimers (Li, Cheng, Xu, 2007;Chabre, Roy, 2008), cyclodextrins (Fulton, Stoddart, 2001;Gomez-Garcia, 2012;Martínez, Ortíz Mellet, García Fernández, 2013), cyclopeptides (Galan, Dumy, Renaudet, 2013), fullerenes (Nierengarten, 2010), gold nanoparticles and quantum dots (El-Boubbou, 2011;Marradi et al, 2013) provide nanoscale materials with anti-adhesive and cell targeting properties.…”

The Revival of Fullerenes?

“…Recently, in a collaborative work, we have shown that this amphiphilic character of sugar-fullerene conjugates can be avoided by synthesizing hexakis-adducts of [60]fullerene in which the C 60 sphere is completely surrounded by sugar moieties in a T-symmetrical octahedral addition pattern. 29 In fact, some of the advantages of fullerenes in comparison to other carbon nanostructures are related to its 3D structure and the possibility to functionalize different positions of the C 60 cage in a controlled fashion. 30 In this sense, fullerenes can be considered very attractive spherical scaffolds for a multivalent presentation of ligands in a globular shape.…”