Synthesis and characterization of oligosaccharides tethered to gold films and gold nanoparticles

The goal of this research was to stereoselectively synthesize alpha- and beta-linked glucopyranosylamide derivatives utilizing the modified Staudinger methodology and to tether these derivatives to gold films and gold nanoparticles. The key step in the synthesis of the glucopyranosyl conjugates is the coupling of a glycosylazide to an acid derivative in the presence of either triphenylphosphine or trimethylphosphine. The synthesis proceeds via the in situ generation of glucosyl isoxazoline intermediate. The characterization of the resulting films and particles has been performed using Fourier-Transform Infrared (FT-IR), Atomic Force Microscopy (AFM), and X-Ray Photoelectron Spectroscopy (XPS). The XPS and AFM analyses have shown evidence for monolayer and multilayered films depending on the derivative used. Glucopyranosyl derivatives with free hydroxyl groups gave well ordered, self-assembled monolayers (SAMs). FT-IR and XPS analysis of the SAMs demonstrated that the resulting monolayers were comprised of a hydrogen bonded network between amides on adjacent sites. (Abstract shortened by UMI.)...