Natural product to modern discovery of their active ingredients and eventually to the development of new drugs. A large number of currently prescribed drugs have been either directly derived from or inspired by natural products. A few representative examples are listed below. Some of the oldest natural product based drugs are analgesics. The bark of the willow tree has been known from antiquity to have pain relieving properties. This is due to presence of the natural product salicin which in turn may be hydrolyzed into salicylic acid. A synthetic derivative acetylsalicylic acid better known as aspirin is a widely used pain reliever.
Fluoroacetic acid Fluoroacetic acid Fluoroacetic acid is a chemical compound with formula CHFCOOH. The sodium salt, sodium fluoroacetate, is used as a pesticide. It inhibits the aconitase step of the citric acid cycle. Fluoroacetate occurs naturally in at least 40 plants in Australia, Brazil, and Africa. It is one of only five known organic fluorine-containing natural products. It was first identified in "Dichapetalum cymosum", commonly known as gifblaar (Afrikaans) or poison leaf, by Marais in 1944. As early as 1904, colonists in Sierra Leone used extracts of "Chailletia toxicaria", which also contains fluoroacetic acid or its salts, to poison rats. Several native