Multicomponent Tandem Synthesis of Oxospirobicyclic Butenolidobarbiturates

Abstract

Novel oxospirobicyclic γ-butenolides containing barbiturate moiety have been synthesised by the Michael-addition of primary amines to dialkyl acetylenedicarboxylates followed by aldol-like reaction with alloxan derivatives, and then γ-lactonisation. Subsequent 1,4-addition of water and elimination of the amine group completes the sequence. This tandem reaction sequence represents a rapid and unprecedented route to the described biologically interesting molecules.