Fluorescent Receptors for Biomolecules

The development of synthetic receptors capable of high-affinity complexation of biologically relevant analytes in competitive solvent systems represents an ongoing challenge in molecular recognition. Anion recognition is particularly problematic, which is significant since numerous biological processes are regulated by anions, such as those resulting from phosphorylation. In this dissertation, we present the design and synthesis of a fluorescent sensor containing two cyclen groups that are preorganized to form a binding cleft for anion complexation. The receptor design includes a rigid acridine backbone, which is also exploited for fluorescence signal transduction. Furthermore, click chemistry is employed to facilitate receptor synthesis, and binding studies with various phosphorylated guest molecules are described. Additionally, the development of boronic acid-based carbohydrate receptors is presented. Carbohydrates play important roles in a large number of biochemical processes such as signal transduction and cell surface recognition events. The receptors will be used to study carbohydrate binding through Förster resonance energy transfer (FRET) and surface enhanced Raman spectroscopy (SERS). Another project involves the synthesis of aromatic compounds that can act as auxin herbicides. Auxins are plant hormones that play a major role in the regulation of plant growth and development. A modular synthetic strategy is employed to access a library of small molecules that will be tested for herbicidal activity on a variety of weeds. Finally, the work on the design and synthesis of molecular building blocks to generate covalently-bonded ordered organic frameworks is discussed