Homo- or copolymerisation of unsaturated carbohydrate derivatives yields synthetic polysaccharides with a chemically and biologically stable C-C backbone and pendent hydrophilic carbohydrate residues (carb), so-called 'glycopolymers'.
They have been found to be especially useful for biomedical and pharmaceutical research and practical medical applications. Saccharide units in glycopolymers can be capable of molecular recognition and interact with specific carbohydrate receptors. Therefore, they are interesting materials for biomimetic models of glycoconjugates and also for therapeutic or diagnostic purposes in biomedical fields. Furthermore, the properties of glycopolymers suggest that they have much potential as suitable materials for drug-delivery systems (e.g. "polymer drugs"). The therapeutic agent is incorporated in a polymer matrix and released in the human body in a controlled manner. Main requirements for polymer drugs are water-solubility, biocompatibility, tendency to accumulate at the target site, controlled release and sufficient rate of biodegradation and elimination from the body. The polymer matrix and all degradation products should be physiologically safe. In most cases the synthesis of well-defined glycopolymers demands the use of protective groups to overcome the polyfunctionality of carbohydrates. Chemical transformations of unprotected sugars are feasible starting from amino sugars and lactones and also glucosidic hydroxy groups can be reacted selectively with specific catalysts. Both strategies were applied in order to synthesize carbohydrate monomers (methacrylates, maleimides) based on glucose, maltose, cellobiose, sucrose, glucamine, glucosamine and glucono-1,5-lactone. By radical homo- and copolymerization a variety of glycopolymers was obtained.