Eight-Membered Ring Heterocycles

Abstract This chapter discusses about the structural aspects, chemical reactivity, biological significance and synthesis of diverse saturated, partially saturated and unsaturated eight membered heterocycles. It starts with a brief discussion about the structural characterization and reactivity of various nitrogen, oxygen, sulfur and mixed heteroatom containing eight membered systems. The next section is devoted towards the importance of these scaffolds in medicinally relevant naturally occurring molecules. In addition, a variety of synthetic strategies for the construction of eight membered isolated and aryl-fused heterocycles along with their chemical transformations are presented. Besides these traditional heterocyclic systems, the synthesis of an eight-membered oxazaborocine analogue by using ring expansion strategy has also been described.