Large-Scale Preparation of N-Butanoyl-l-glutathione (C4-GSH)

A novel two-step synthesis of N-butanoyl-l-glutathione (C4-GSH) was developed involving the chemical modification of the commercially available starting material l-glutathione (GSH). This process not only has the advantage of selective acylation of the GSH amino group without the use of previous solid-phase organic synthesis and/or protecting group chemistry but also highlights the use of inexpensive reagents such as butyric anhydride and sodium methoxide as well as environmentally acceptable solvents such as water and methanol. This chromatography- and salt-free synthesis of C4-GSH is cost-effective, safe, efficient, and easy to scale up.