Rodenticides discovery

The Discovery and Development of Bromethalin, an Acute Rodenticide with a Unique Mode of Action... 

Because rodent populations world-wide were becoming resistant to the widely used Warfarin-type anticoagulant poisons, a search was initiated to find a rodenticide with a different mode of action one that would be effective against these resistant rodents. This search led to the discovery of the toxic nature of a family of diphenyl amines which act as uncouplers of oxidative phosphorylation. A structure-activity relationship (SAR) study was undertaken to choose a derivative that would be both poisonous to rodents but still readily consumed by them. This approach led to the discovery of bromethalin,... 

In retrospect, it seems probable that the medical profession gained far more from Link s successes as an agricultural chemist than it could have from his practice of medicine. The discovery of Dicumarol and its adoption as an important clinical anticoagulant, and the synthesis of Warfarin and its development as a widely used rodenticide—these accomplishments, which will not be described in this article, alone were more than sufficient to make Karl Link an important name in science. For his work on Dicumarol, Link received the Cameron Award from the University of Edinburgh in 1952, the Lasker Award in 1955 and 1960, the John Scott Award in 1959, and the Kovalenko Medal of the National Academy of Sciences in 1967. He was a Harvey Lecturer... 

The discovery of brassinolide by scientists at USDA led to the development of a new group of plant growth substances, termed brassinosteroids, which have the potential for increasing crop yields and biomass. The chapter summarizes the USDA s contributions to brassinosteroids, which include isolation and identification of brassinolide, synthesis of brassinolide and its analogs, and limited biological and field studies on brassinosteroids. An overview of the current data requirements for the registration of brassinosteroids as biochemical pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act is presented. 

Because of its anticoagulant activity for blood, this compound is used as a rodenticide. For the story of the discovery of the anticoagulant dicoumarin, see "Chemical Connections From Moldy Qover to a Blood Thinner" in Chapter 18. 

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