Advances in Heterocyclic Chemistry, Volume 140 is the latest release in this definitive series in the field of heterocyclic chemistry, one of great importance to organic chemists, polymer chemists, and many biological scientists. Written by established authorities in the field from around the world, this comprehensive review combines descriptive synthetic chemistry and mechanistic insight to yield an understanding of how chemistry drives the preparation and useful properties of heterocyclic compounds. Chapters in this new release include The chemistry of citrazinic acid (2,6-dihydroxyisonicotinic acid), Aza-Diels-Alder Reaction in the Synthesis of Tetrahyroquinoline Structures, and more. Additional chapters delve into Recent Developments in the Synthesis of 4-, 5-, 6- and 7-Azaindoles, Fluoroheterocycle formation using fluoroalkynes and their synthetic equivalents, Advances in applications of dihydropyridines in organic chemistry, and Recent Developments in the Chemistry of Triphyrins (2.1.1).