Figure 9.

Herbicidal activities of picloram and aminopyralid were discovered 43 years apart. A thorough structure–activity relations exploration after aminopyralid discovery led to the novel arylpicolinate synthetic auxin herbicide class. The long soil half‐life of the highly active arylpicolinate analog (DAS402) was reduced by introducing a methoxy group to the 3‐position of the phenyl tail resulting in the analog, halauxifen‐methyl (Arylex™ Active). Further exploration resulted in the discovery of florpyrauxifen‐benzyl (Rinskor™ Active).