Frontiers

Good Chemistry

Doctoral candidate Gretchen Stanton improves efficiency in reactions.
September 2012

Chemistry is all about the details. While lab work might revolve around scientific discovery, practicalities like time and money are inevitable byproducts. Gretchen Stanton, a chemistry doctoral candidate, is working to combat low efficiency reactions by researching easier ways to build molecular complexity. The major technique she employs is called the one-pot reaction, which speeds the product isolation and purification stages using multiple reactions sequentially. This works to eliminate waste and alleviate costs. “Chemists, whether working in academia or in the pharmaceutical industry,” says Stanton, “can use our methods as a tool to make new biologically active compounds or natural products that may otherwise be very difficult to synthesize.”

Stanton is currently working in a lab in Spain that specializes in heterogeneous catalysis. This method is similar to the one-pot in that it decreases the amount of reagents needed in any given reaction. With this method, researchers can attach a catalyst to a solid support so that it can be recovered and reused. Catalysts are important for testing reactions because they lower the energy barrier needed for a reaction to occur, therefore making the process faster.

“Chemists, whether working in academia or in the pharmaceutical industry, can use our methods as a tool to make new biologically active compounds or natural products that may otherwise be very difficult to synthesize.” - Gretchen Stanton

While still in the early stages, Stanton is also involved in research that has broad implications for pharmaceutical product safety. The process, called asymmetric selectivity, involves the introduction of an organozinc reagent to a reaction in order to investigate possible harmful side effects. “Many compounds exist as a mixture of two mirror images called enantiomers,” says Stanton. “They might look essentially the same, but they may have very different biological properties. With an asymmetric reaction we are able to isolate the ‘right hand’ from the ‘left hand’ in order to learn more about the compound.”

One example of a drug with both harmful and beneficiary effects is the infamous thalidomide, which was introduced in the 1950s as a treatment for morning sickness and sleep disorders. It soon became evident that the product’s harmful mirror image was responsible for widespread birth defects. Working to combat this type of occurrence, Stanton’s lab uses existing models to establish product A within a compound, achieved by adding a protective group, or chemical modification. Once this has been determined, an organozinc reagent is added to reverse the selectivity and produce product B. “Experimenting with these groups allows us to better understand the different aspects of a compound,” says Stanton. “Our hope is that the companies making these pharmaceuticals will apply our methods, especially since the industry currently doesn’t make much use of organozinc reagents.”