Provides an introduction to the complex chemistry of heterocycles and an overview of the many and varied applications of this versatile class of compounds. The only book to examine the multidisciplinary applications of heterocycles, it features descriptions of the impact of heterocyclic compounds in living organisms: in the structure of DNA, enzymes and proteins, vitamins and antibodies and their role in plants and animals. The use of the compounds in the chemical industry is also covered. It is written in non-technical language by top researchers and includes problems at the end of each chapter.