Chapter 11: Coumarins

Coumarins are naturally occurring, aromatic secondary messengers with a benzopyrone scaffold and they have aroused significant interest due to their bioactivity and pharmacological properties. Coumarins occur in many different microorganisms, few animals and ubiquitously in plants such as grasses, papilionaceaes, tonka beans, in yellow melilots, Chinese cinnamon, woodruff, mahaleb cherry and dates. Although a huge number of pathways for the syntheses of coumarins are known, new routes to access coumarin derivatives still gain a high value in the field of organic synthesis. The possible applications of coumarins are manifold. They are not only used in medicinal chemistry but also e.g. for living cell imaging based on their fluorescent properties.