Well known for its vanilla-like fragrance, coumarin has been synthesized in the laboratory since 1868 and is commonly utilized in the production of perfumes. Despite its aromatic smell, however, the compound generally has a bitter taste. In fact, in lavender, sweet clover, strawberry, licorice, and other plants, coumarin is believed to act as form of defense against insects, which seem to be repelled by the taste of the substance. A coumarin derivative commonly known as warfarin is apparently even more distasteful, gaining use as a rat poison since the 1940s. This same compound was introduced for medical use in 1954 and has been widely utilized as an anticoagulant ever since.