Solid-phase synthesis of the 2(1H)-pyrazinone scaffold: a new approach toward diversely substituted heterocycles.

The first solid-phase synthesis of the 2(1H)-pyrazinone scaffold is described. The diversity at position C6 of the pyrazinone ring is determined by the choice of the starting aldehyde. Microwave-enhanced transition metal-catalyzed reactions allow easy introduction of a variety of substituents at the C3 position. This opens a way for the generation of libraries of diversely substituted 2(1H)-pyrazinones that will be screened for biological activities.