Pyrethroid insecticide

Pyrethroids insecticides are synthetic analogs of natural pyrethrins. Natural pyrethrins were widely used in Europe during the 19th century, when few effective insecticides were available.

The chemical class of pyrethroids is divided into structurally related subclass.
Type I Pyrethroids
Type II Pyrethroids
Non-ester Pyrethroids

The type I pyrethroids are ester bond pyrethroids without α-cyano-residue, the type II pyrethroids include all ester bond pyrethroids containing a cyano-group at the α-carbon atom.

Pyrethroids insecticides are generally recognized as potent neurotoxicants that interfere with nerve membrane function by interaction with the sodium channel.

Synthetic pyrethroids are more toxic against insect pests, up to ten times more potent in some cases, than the other insecticides now in general use.

The development of the synthetic pyrethroids arguably is one of the most commercially successful classes of conventional insecticides.

What made the synthetic pyrethroids useful for agricultural was their reduced photolability in the presence of sunlight through halide substitution of the parent chrysanthemic acid and replacement of the butenolide ring with a more stable 3-phenocyphenuyl ring system.
Pyrethroid insecticide