CARB 62

Due to their ability to form tight and reversible complexes with diol-containing compounds such as carbohydrates, boronic acids are very useful building blocks for the preparation of sugar sensors and lectin mimics. Along this line, we have discovered that 8-quinolineboronic acid is a very unique fluorescent reporter because of its ability to increase fluorescent emission intensity upon sugar binding. Crystallographic, fluorescent spectroscopic, and NMR studies indicate that the mechanism through which this fluorescent intensity change occurs is through the formation of a self-assembled dimeric complex of the free boronic acid in protic solvents. The disruption of the self-assembled form is most likely the reason for the fluorescent intensity changes upon sugar binding. The presentation will discuss the results of the spectroscopic and crystallographic studies of two quinoline boronic acids in an effort to elucidate the mechanistic details.