Recent Applications of Multicomponent Reactions Toward Heterocyclic Drug Discovery

Multicomponent reactions (MCRs) date back to the mid-1800s and are widely used today as they offer increased atom efficiency, high molecular diversity, and often heterocycle formation in just one step. As such, it is incumbent on any synthetic chemist to be well versed in the domain of MCRs as the fields of pharmaceuticals and natural product chemistry are largely dominated by heterocycles. This chapter discusses recent applications of MCRs toward heterocyclic molecules particularly in the areas of drug discovery and natural products, employing well-established reactions (Ugi, Passerini, Groebke–Blackburn–Bienaymé (GBB), Gewald, Hantzsch, Biginelli, and van Leusen). The modifications of the heterocycles are also examined in regard to their structure–activity relationships and biological implications.