Pyrethrin analogues insecticidal activity

Many natural products and biologically active compounds contain cyclopropane rings we shall feature j ist a few. First, a most important natural insecticide, a pyrethrin from the East African pyrethrum daisy, and its synthetic analogue decamethrin, now the most important insecticide in agriculture (see Chapter 1). Very low doses of this highly active and nonpersistent insecticide are needed. 

Phenvalera te)] (chlorinated aryl carboxylic acid ester) analogue of Pyrethrin I sensitive TTX-resistant) activator (persistent open state depolarization, block, paralysis) [insecticide, proconvulsant, toxic]... 

Pyrethroid insecticides are widely used because of their high activity as an insecticide and low mammalian toxicity. Pyrethroids are in group 3, sodium channel modulators. The pyrethroids have a highly nonpolar nature, low water solubility, and high affinity to soil and sediment particulate matter. Natural pyrethrin is extracted from the flowers of Chrysanthemum spp., and its use was already known in China in the first century A.D. Pyrethroids, synthetic analogues of pyrethrin, have been produced since 1940 [26]. 

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