Functionalization of carbohydrates toward metal binding

Date of Completion

January 2004


Chemistry, Organic




Carbohydrates are neutral, oxygen-rich and water-soluble compounds which are potentially useful in the chelation of metals of biological interest. However, naturally occurring carbohydrates such as the monosaccharides D-glucose or D-galactose possess only weak metal binding properties. Thus, the development of synthetic strategies toward the synthesis of carbohydrate derivatives carrying strong metal binding moieties were investigated. The syntheses using D-glucose and D-galactose as starting materials involves key oxidation steps that are emphasized in this work. A detailed study of the oxidation of unprotected and partially protected monosaccharides using oxoammonium salts as catalytic and stoichiometric oxidants is presented. Specifically, the syntheses of aldaric acids and aldolactones are reported. The aldolactones are key intermediates in the synthesis of metal-chelate carrying C-glycosides, carbohydrate analogues which are resistant to metabolic degradation. The chelating moieties chosen were 1,3-diketones, catechols and hydroxamic acid functionalities. The methodologies developed allow the preparation of a range of metal-binding carbohydrate derivatives decorated with a diverse set of functionalities. ^