Attempts to prepare tethered bilayer lipid membranes using synthetic thioglycolipid anchors: synthesis of 6″-thiotrisaccharide glycolipid analogues and applications.
The synthesis of the three 6″-deoxy-6″-thio glycolipid analogues β-d-Gal-(1→6)-β-d-Gal-(1→4)-β-d-Glu-(1→OCH2)-[1,2,3]-triazole-1-dodecane, β-d-Gal-(1→4)-β-d-Glu-(1→4)-β-d-Glu-(1→OCH2)-[1,2,3]-triazole-1-dodecane and β-d-Gal-(1→4)-β-d-Glu-(1→4)-β-d-Glu-(1→OCH2)-[1,2,3]-triazole-1-octadecane is presented. Glycosylation at position O-4' of a propargyl cellobioside glycosyl acceptor and position O-6' of a propargyl lactoside glycosyl acceptor with a 6-deoxy-6-thio galactosyl donor gave rise to two unique trisaccharides that in turn underwent copper-catalyzed azide-alkyne cycloadditions with either 1-azidododecane or 1-azidooctadecane. The potential for each of these analogues to function as tethers of lipid bilayers to Au(111) surface was assessed by differential capacitance experiments. A monolayer of the previously described monosaccharide 1-octadecane-4-(6-thio-β-d-galacto-pyranosyloxymethyl)-[1,2,3]-triazole either self-assembled or prepared by Langmuir-Blodgett (LB) transfer was found to support an outer leaflet monolayer (DMPC/cholesterol, 70:30) deposited by Langmuir-Schaefer (LS) touch. The bilayers obtained with this monosaccharide analogue had minimum differential capacitances of 1.0 and 0.9μF/cm(2) when the inner monolayer was prepared by self-assembly and LS touch, respectively. Attempts to produce bilayers using the trisaccharides synthesized here were unsuccessful; we are attributing these unsuccessful results mostly to the high water solubility of trisaccharides combined with the relatively short length of the hydrocarbon chains used in this study.
Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Serena
S
Singh
Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Zhangfei
Z
Su
Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
Michael
M
Grossutti
Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada. Electronic address: fauzanne@uoguelph.ca.
France-Isabelle
FI
Auzanneau
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002384:Catalysis; D057930:Click Chemistry; D003300:Copper / Q000737:chemistry; D061565:Cycloaddition Reaction; D006017:Glycolipids / Q000138:chemical synthesis*; D008051:Lipid Bilayers / Q000737:chemistry*; D008969:Molecular Sequence Data; D014312:Trisaccharides / Q000138:chemical synthesis*
D006017:Glycolipids; D008051:Lipid Bilayers; D014312:Trisaccharides; D003300:Copper
Artificial bilayer lipid membranes; Click chemistry; Thiotrisaccharide glycolipids