Chrysanthemic acid is an organic compound

Organic compound

An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

 that is related to a variety of natural and synthetic insecticide

Insecticide

An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...

s. It is related to the pyrethrin

Pyrethrin

The pyrethrins are a pair of natural organic compounds that have potent insecticidal activity. Pyrethrins are neurotoxins that attack the nervous systems of all insects. When present in amounts not fatal to insects, they still appear to have an insect repellent effect. Pyrethrins are gradually...

 I and II, as well as the pyrethroid

Pyrethroid

A pyrethroid is an organic compound similar to the natural pyrethrins produced by the flowers of pyrethrums . Pyrethroids now constitute a major commercial household insecticides...

s. One of the four stereoisomers, (1R,3R)- or (+)-trans-chrysanthemic acid (pictured), is the acid-derived group of pyrethrin I

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 --pyrethrolone.- Total synthesis:...

, which occurs naturally in the seed cases of Chrysanthemum

Chrysanthemum

Chrysanthemums, often called mums or chrysanths, are of the genus constituting approximately 30 species of perennial flowering plants in the family Asteraceae which is native to Asia and northeastern Europe.-Etymology:...

 cinerariaefolium. Many synthetic pyrethroids, for example the allethrin

Allethrin

The allethrins are a pair of related synthetic compounds used in insecticides. They are synthetic pyrethroids, a synthetic form of a chemical found naturally in the chrysanthemum flower. They were first synthesized in the United States by Milton S. Schechter in 1949...

s, are esters of all four stereoisomers.

Biosynthesis

Chrysanthemic acid is derived from its pyrophosphate

Pyrophosphate

In chemistry, the anion, the salts, and the esters of pyrophosphoric acid are called pyrophosphates. Any salt or ester containing two phosphate groups is called a diphosphate. As a food additive, diphosphates are known as E450.- Chemistry :...

 ester, which in turn is produced naturally

Biosynthesis

Biosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...

 from dimethylallyl diphosphate.

Synthesis

Chrysanthemic acid is produced industrially in a cyclopropanation reaction of a diene

Diene

In organic chemistry a diene or diolefin is a hydrocarbon that contains two carbon double bonds.Conjugated dienes are functional groups, with a general formula of CnH2n-2. Dienes and alkynes are functional isomers...

 as a mixture of cis- and trans isomers, followed by hydrolysis of the ester:

Many pyrethroids are accessible by re-esterification of crysanthemic acid ethylester.