Recent Advances in the Synthesis of α-Alkylidene-Substituted δ-Lactones, γ-Lactams and δ-Lactams
α-Alkylidene-substituted δ-lactones and corresponding γ- and δ-lactams constitute important classes of natural compounds that display diverse biological activities. This review gives a brief description of the occurrence and biological activities of the title compounds and then summarizes the methods available for their preparation. Attention is given mainly to the synthetic approaches developed during the last decade, including those from our own research group. The latest developments in the synthesis of nonracemic α-alkylidene-substituted δ-lactones, γ-lactams and δ-lactams are also discussed.