A cost-effective synthesis of enantiopure ovothiol A from L-histidine, its natural precursor

Ovothiol A is a naturally occurring 4-mercaptohistidine derivative, and one of the most potent thiol-containing antioxidants. The synthesis of ovothiol A was elaborated by introducing the thiol group onto protected 3-methyl-L-histidine via halogenation and Ullmann reaction. This enantiopure synthesis of ovothiol A, which uses L-histidine as starting material, requires only five steps, and compared to prior synthesis, is both cost and time effiecent.