Modeling Boronic Acid Based Fluorescent Saccharide Sensors: Computational Investigation of d-Fructose Binding to Dimethylaminomethylphenylboronic Acid (DMPBA)

Phenylboronic acids have been shown to selectively bind saccharides in solution, an excellent tool for modular, synthetic design of fluorescent saccharide sensors. In 2010 Larkin et al described the binding motifs between several saccharide monomers and oligomers, however they were unable to identify the exact binding motif of d-fructose to such phenylboronic acid receptors, although d-fructose is known to bind (as titration of d-fructose in solution with anthracene linked receptors results in increased fluorescence). In this work, we use quantum mechanical geometry optimizations to predict the lowest energy binding modes between fructose monomers and a model fluorescent receptor. In understanding which binding motifs are lowest in energy, and therefore most likely, we can hopefully move on to QM/MM free energy simulations in explicit solvent to extract more refined results. 

In conjunction with recently submitted results, we have provided here all quantum chemical (QChem 4.3) input and output files detailing our work. Any interested parties can use the files to obtain exact calculation settings, as well as extract coordinates for each of the 26 predicted binding motifs before and after optimization in gas and implicit solvent and using several method/basis set combinations.