HETEROCYCLIC CHEMISTRY is written keeping in mind the requirements of graduate and postgraduate students and students appearing in various competitive examinations. It deals with the fundamentals of heterocyclic chemistry, including importance, classification and nomenclature of heterocyclic compounds. The book discusses chemistry (methods of synthesis, reactions and importance) of three-membered heterocyclic compounds (containing one or two heteroatoms), four-membered heterocyclic compounds, five membered heterocyclic compounds (containing one or two or more than two hetero atoms) alongwith their benzofused derivatives and six-membered heterocyclic compounds (containing one or more than O, N or S heteroatoms) alongwith their benzofused derivatives. The incorporation of pyridazine, pyrimidine and their derivatives alongwith their fused derivatives has special importance. Seven-membered heterocyclic compounds and meso-ionic heterocycles have also been included.