Reducing the production of waste in the synthesis of LAGEVRIO™ (molnupiravir), an antiviral treatment for COVID-19

This case study is based on the 2022 Greener Synthetic Pathways - Green Chemistry Challenge Award (GCCA) which was won by Merck for the synthesis of the COVID-19 antiviral molnupiravir (LAGEVRIO TM). This GCCA is a good example of designing and comparing the efficacy of multi-step syntheses. The revised, biocatalytic synthesis of molnupiravir dramatically reduces the production of waste compared to the traditional synthetic pathway. The case study provides an opportunity for students to learn to think about the waste generated during a synthesis, including the solvents, unreacted starting materials, and the by-products that are often ignored when writing organic chemical reactions. This case study will attract student interest as molnupiravir is a COVID-19 antiviral, and many will recall the significant impact that the development of treatments and vaccines had on daily life.