Four-Membered Heterocycles

Abstract In this chapter, chemistry and structural aspects along with medicinal importance of four-membered saturated and unsaturated mono N, O, and S heterocycles such as azetidine, azetidin-2-ones, azetines, azete oxetane, oxetanone, oxetene, and thietane are discussed. Besides monoheteroatom heterocycles the chemistry of compounds with two similar and dissimilar heteroatoms such as 1,2-diazetidine, 1,3-diazetidine, 1,2-dioxetane, dithietanes, oxazetidines, thiazetidines, and 1,2-oxathietane are also delineated.