Recent Advances in the Chemistry of Glycoconjugate Amphiphiles

Abstract

Glyconanoparticles essentially result from the (covalent or noncovalent) association of nanometer-scale objects with carbohydrates. Such glyconanoparticles can take many different forms and this mini review will focus only on soft materials (colloids, liposomes, gels etc.) with a special emphasis on glycolipid-derived nanomaterials and the chemistry involved for their synthesis. Also this contribution presents Low Molecular Weight Gels (LMWGs) stabilized by glycoconjugate amphiphiles. Such soft materials are likely to be of interest for different biomedical applications.

Hierarchical Self‐Assembly of Amphiphilic β‐C‐Glycosylbarbiturates into Multiresponsive Alginate‐Like Supramolecular Hydrogel Fibers and Vesicle Hydrogel

“…[12] For practical synthesis reasons, the conjugation of carbohydrates to hydrophobic segments takes place at the reducing end position leading to linear glycoamphiphiles. [13] However, the reducing-end modification of carbohydrates still entails laborious and time-consuming protection-deprotection multisteps, which incites the glycochemist community to develop various protecting-group-free strategies. [14] We recently reported a convenient direct reducing-end modification of unprotected carbohydrates through N,N'-disubstituted barbituric-mediated Knoevenagel condensation in water.…”

Synthesis and Self-Assembly Properties of Bola-Amphiphilic Glycosylated Lipopeptide-Type Supramolecular Hydrogels Showing Colour Changes Along with Gel–Sol Transition

“…We designed and synthesized the glycosylated lipopeptide-type bola-amphiphiles with the general formula β-D-galactose (βGal)–AAC–C6–F n ( n = 1–4) ( Figure 2 , Scheme 1 ). The saccharide structure and hydrocarbon chain length are essential factors for the self-assembly property of glycolipid-type amphiphiles [ 36 , 40 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. We fixed the saccharide structure as βGal and hydrocarbon chain length as the C6 spacer based on the previous study [ 40 ].…”

β-N-Acetylhexosaminidases for Carbohydrate Synthesis via Trans-Glycosylation

“…Most noteworthy in this context is the recently reported synthesis of LNT II where an isolated yield of 86% (281 g/L) was achieved in a reaction using Lac and Glc-oxa in a ratio of 1:1 at a concentration of 600 mM each (Table 9) [100]. [51] NoHex (Nocardia orientalis 1 donor based; 2 isolated yield(s); 3 isolated as deprotected conjugates; 4 purified from β-galactosidase preparation (grade XI, Sigma-Aldrich); 5 2% diglycoside observed; 6 enzyme source not specified; 7 carried out in a plasticized glass phase: 10% H 2 O, 5% EtOH, 5% n-PrOH; 8 donor added stepwise; 9 isolated from Taka-diastase (Sankyo); 10 t-butanol gave no product; 11 not isolated; 12 only detected by TLC; 13 or Amycolatopsis orientalis IFO12806T; 14 only aliphatic OH of coniferyl alcohol glycosylated; 15 1,3-butanediol and 1,2,4-butanetriol gave no product, but enhanced chitotriose formation; 16 no product formation with dulcitol; 17 Phenyl-and 2-chlorophenylglycosides were cleaved overnight, the other two were stable; 18 thioglycoligase reaction; 19 30% (v/v) MeCN added; 20 5% (v/v) DMSO added; 21 10 mM DTT added.…”

“…Other possible GlcNAc-containing products are non-reducing oligosaccharides as found in some antibiotics (e.g., tunicamycin [12] or orthosomycins [13]), chitooligomers, for which antioxidative [14,15] and antiangiogenic effects [16] have been demonstrated, and branched glycans/oligosaccharides (e.g., HMOs) ( Figure 1). Alkylated GlcNAc moieties are part of molecules that can be used as glycosurfactants [17,18] or bivalent lectin ligands [19,20], GlcNAc-modified drugs and vitamins have a higher solubility in water [21,22], and GlcNAc-modified amino acids and glyco-engineered proteins are important for optimal bioactivity [23,24].…”