flumethrin

Flumethrin is a pyrethroid insecticide and acaricide. It is used externally in veterinary medicine against parasitic insects and ticks on cattle, sheep, goats, horses, and dogs, and the treatment of parasitic mites in honeybee colonies.

==Chemistry== Flumethrin is a complex mixture of stereoisomers. The molecule contains three asymmetric carbon atoms, there is cis-trans isomerism at the cyclopropane ring, and E/Z isomerism at the carbon-carbon double bond of the alkene. So there are 16 different isomers. Commercial flumethrin typically contains 92% of the trans isomers on the cyclopropane ring and the Z configuration at the olefinic carbon-carbon double bond and 8% of the isomer with cis geometry on the cyclopropane ring and the Z configuration at the olefinic carbon-carbon double bond.