Editorial [Hot Topic:New Directions in the Chemistry and Biology of Carbohydrates (Guest Editor: Robert M. Giuliano)]

The idea for this special issue of Current Topics in Medicinal Chemistry was generated during a Gordon Research Conference on Carbohydrates that I attended in 2005. Having attended several of these conferences over the past 25 years, I was struck by the growth in our understanding of the chemistry and biology of carbohydrates, and the possibilities that now exist for the application of that understanding to the development of new therapies in medicine. It seemed an appropriate time to bring wider exposure of the advances in carbohydrate science to the medicinal chemistry community. The important role that cell-surface carbohydrates play in biological interactions has come to be widely appreciated as tools have been developed for the chemical synthesis and study of carbohydrate-protein and carbohydrate-lipid conjugates. Glycoconjugates on the surface of a cell provide receptors for cell-cell recognition at the molecular level, and are involved in such processes as the regulation of cell growth and repair, cell adhesion and migration, and in pathological conditions such as tumor metastasis in cancer. Our recognition of the roles that carbohydrates play in these processes will continue to inspire research in the field of synthetic vaccines, a topic that is featured in several of the articles in this issue. The use of synthetic vaccines incorporating oligosaccharides holds promise in the treatment of bacterial infections, and also in the treatment of AIDS and cancer. Understanding the biosynthesis of cell-surface oligosaccharides is also important to the identification of potential targets for pathogenic organisms, and the use of vaccine adjuvants has been expanded to include carbohydrate mimetics of lipid A that interact with toll-like receptors. The anticoagulant heparin, a glycosaminoglycan, is one of the most widely prescribed medications in the world. The pharmacokinetics and pharmacodynamics of heparin may be improved through the use of immobilized heparins, which also have potential for applications in regulating other biological pathways. Carbohydrate-based drugs are finding new applications in the treatment of CNS disorders, and pyranose N-glycosyl amines have been found to have a range of interesting biological activities and potential in the treatment of infection and inflammation. New synthetic methodology will always find important applications in the development of carbohydrate-based drugs of the complexity found in this issue. A review on the use of ultrasound and microwaves in carbohydrate chemistry and one on palladium-catalyzed glycosylation describe advances in carbohydrate synthesis by these methods. Our ability to synthesis complex, carbohydrate-derived therapeutic agents, coupled with our increased understanding of the roles of glycoconjugates in biology will hopefully lead to promising treatments for a wide range of diseases.