About the book
Azoles represent a broad class of five-membered heterocycles containing one or several nitrogen atoms, with the possible inclusion of other heteroatoms (e.g., O, S) in the ring. The parent compounds are aromatic and have two double bonds. Also, there are successively reduced analogs (azolines and azolidines) with fewer double bonds. One, and only one, lone pair of electrons from each heteroatom in the azole ring is part of the aromatic bonding. Such compounds as imidazole and other five-membered aromatic heterocyclic systems with two nitrogens are extremely common in nature and form the core of many biomolecules, e.g., histidine. Azoles have always been considered as molecules of choice in designing novel therapeutic agents. Various oxygen-containing azoles such as oxadiazoles, oxazoles, and isoxazoles have been investigated for their diversified biological activities. Other examples of azole usage include functionalization of titanium oxide clusters by azole ligands with the formation of novel titanium−azole molecular clusters with Ti−N bonds to create photocatalytically active compounds, and synthesis of amino, azido, nitro, and nitrogen‐rich azole substituted derivatives of benzotriazole for energetic material applications. Thus, azoles are compounds with rich and versatile chemistry and numerous (potential) applications, which should be properly reviewed and summarized.