My basic area of research interest is Organic Synthesis. Within this broad area, I have two areas under active investigation: deep eutectic solvents and the exploration of aurones as biologically active natural products and fluorophores.

Deep eutectic solvents (DES) are extreme examples of a very common phenomenon - melting point depression. It is well known that a mixture of two compounds will exhibit a melting point depression compared to each individual pure compound. In most cases, this depression is only a few degrees. In the case of DES, however, the depression is quite extreme (deep) and is also highly dependent on the molar ratio of the two materials. Thus, the combination of choline chloride (mp >300 C) and urea (mp roughly 128 C) in a 1:2 molar ratio affords a mixture with a melting point around 10 C - a liquid at room temperature. As both starting compounds are inexpensive, non-flammable, and non-toxic, this DES is an appealing solvent alternative. My group has observed that it also can serve as a very mild catalyst for a number of different reactions. We are continuing to explore further applications in organic synthesis as well as other DES that might have additional catalytic activities.

The aurone project features the use of DES to synthesize the aurone framework by the condensation of an aldehyde with a benzofuranone. Aurones themselves have been known to be responsible for the golden yellow coloration of the flowers of many plants. As a small sub-set of the flavonoids, it is not surprising that they exhibit a wide range of biological activities. At the same time, their low natural abundance has made this potential hard to use. Via synthesis, we have been able to prepare a significant number of new aurone variations (analogs) and, by active collaboration with many faculty in the Biology department, explore activities ranging from anti-microbial and anti-fungal to anti-inflammatory and anti-cancer. Further development of this potential continues as well as extension into the area of materials and dye chemistry.

The aurones also have proven to be quite fluorescent and we have recently reported their application as a sensor for hydrogen sulfide (an environmental contaminent, a natural cell signaling species, and also the compound responsible for skunky beer and wine). Other uses as fluorescent labels, dyes, and probes for various other biological and metallic species are under investigation.