Importance to Life and Industry

Many heterocyclic compounds are biosynthesized by plants and animals and are biologically active. Over millions of years these organisms have been under intense evolutionary pressure, and their metabolites may be used to advantage for example, as toxins to ward off predators, or as colouring agents to attract mates or pollinating insects. Some heterocycles are fundamental to life, such as haem derivatives in blood and the 

Dyestuffs of plant origin include indigo blue, used to dye jeans. A poison of detective novel fame is strychnine, obtained from the plant resin curare (Box 1.6). 

The biological properties of heterocycles in general make them one of the prime interests of the pharmaceutical and biotechnology industries. A selection of just six biologically active pyridine or piperidine 

There are many thousands of other heterocyclic compounds, both natural and synthetic, of major importance, not only in medicine but also in most other activities known to man. Small wonder then that their chemistry forms a major part of both undergraduate and postgraduate curricula. 

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