Synthetic toolbox: Multicomponent reactions

API case study: Praziquantel

Cao et al. have developed a route incorporating a multicomponent reaction for the synthesis of Praziquantel, a drug on the WHO list of essential medicines used for the treatment of schistosomiasis.[1]  An Ugi four component reaction is first applied to produce an acylated intermediate which is subsequently cyclised via a Pictet-Spengler reaction.  This has been demonstrated on a small scale.  This route shows promise as a mass efficient two-step synthesis of Praziquantel and additional benefits are that the by-products from the two steps are water and two equivalents of methanol, and the reaction conditions are mild.


  1. H. Cao, H. Liu and A. Dömling, Efficient Multicomponent Reaction Synthesis of the Schistosomiasis Drug Praziquantel, Chemistry – A European Journal, 2010, 16, 12296-12298.