Chapter 5: Synthetic Receptors for Carbohydrates

The chapter summarizes the design and development of synthetic receptors that can selectively target various types of carbohydrate structures, including monosaccharides, oligosaccharides, and glycoconjugates. Biological carbohydrate receptors are called lectins and X-ray crystal structures of their binding pockets show that effective receptor/carbohydrate association is achieved by a synergistic network of polar and nonpolar interactions. The different categories of synthetic carbohydrate receptors are described (boronic acids, organic macrocycle and cleft-shaped molecules, and metal coordination complexes), along with their binding properties and how they can be utilized for diagnostic or therapeutic applications. Examples include efforts to create solution-state chemosensors for mono- and disaccharides. Also described is recent work to detect cell surface glycoconjugates, which are often disease-specific biomarkers and thus valuable molecular targets for biomedical imaging or drug targeting. The chapter concludes with a summary of current challenges and likely future directions.