Pyrethrin II is an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

that is a potent

insecticide Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...

. It is one of the two

pyrethrin The pyrethrins are a class of organic compounds normally derived from ''Chrysanthemum cinerariifolium'' that have potent Insecticide, insecticidal activity by targeting the nervous systems of insects. Pyrethrin naturally occurs in chrysanthemum f ...

s, the other being

pyrethrin I Pyrethrin I is one of the two pyrethrins, natural organic compounds with potent insecticidal activity. It is an ester of (+)-''trans''- chrysanthemic acid with (''S'')-(''Z'')- pyrethrolone. Total synthesis The synthesis of pyrethrin I involves t ...

. Thousands of tons this mixture are produced annually from chrysanthemum plants, which are cultivated in warm climates.Robert L. Metcalf “Insect Control” in Ullmann’s Encyclopedia of Industrial Chemistry” Wiley-VCH, Weinheim, 2002.

Structure and related compounds

Whereas pyrethrin I is a derivative of (+)-''trans''- chrysanthemic acid, in pyrethrin II one methyl group is oxidized to a carboxymethyl group, the resulting core being called pyrethric acid. Knowledge of their chemical structures opened the way for the production of synthetic analogues, which are called

pyrethroid A pyrethroid is an organic compound similar to the natural pyrethrins, which are produced by the flowers of pyrethrums (''Chrysanthemum cinerariaefolium'' and ''Chrysanthemum coccineum, C. coccineum''). Pyrethroids are used as commercial and hou ...

s. In terms of their

biosynthesis Biosynthesis, i.e., chemical synthesis occurring in biological contexts, is a term most often referring to multi-step, enzyme-Catalysis, catalyzed processes where chemical substances absorbed as nutrients (or previously converted through biosynthe ...

, pyrethrins are classified as

terpenoid The terpenoids, also known as isoprenoids, are a class of naturally occurring organic compound, organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeabl ...

s, being derived from dimethylallyl pyrophosphate.Susan B. Rivera, Bradley D. Swedlund, Gretchen J. King, Russell N. Bell, Charles E. Hussey, Jr., Donna M. Shattuck-Eidens, Wislawa M. Wrobel, Galen D. Peiser, and C. Dale Poulter "Chrysanthemyl diphosphate synthase: Isolation of the gene and characterization of the recombinant non-head-to-tail monoterpene synthase from ''Chrysanthemum cinerariaefolium''" Proceedings of the National Academy of Sciences 2001, volume 98, p 4373-4378.

References

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