Synthesis, Copper Chelation, and Free Radical Scavenging Ability of Edaravone: An Undergraduate Medicinal Chemistry Laboratory Experiment

Heterocycles, more specifically those containing nitrogen, make up a family of molecules with great pharmaceutical potential. Many approved drugs, notably anticancer drugs, contain a nitrogen-based heterocycle. To expose students to this class of molecules, we used the Paal–Knorr reaction for the synthesis of edaravone, a pyrazolone derivative. To further engage students in this synthesis, we linked the preparation of this molecule to the Ice Bucket Challenge. Edaravone was the first molecule approved as a treatment for amyotrophic lateral sclerosis (ALS) in decades, and the Ice Bucket Challenge aims to promote awareness of ALS and encourage donations. The required chemicals and materials for the experiment are readily available, and the synthesis complies with two of the principles of green chemistry. The experiment also involves testing the chelating capacity of copper and the free radical scavenging activity of the synthesized molecule. In addition to the synthesis, students tested their own molecules, which was very rewarding. This laboratory experiment allows students to enhance their knowledge of organic synthesis/characterization. With this experiment, students will develop hands-on operation skills and the ability to integrate theory with practice.