A new selective insecticidal uncoupler of oxidative phosphorylation

Summary A new aryl hydrazone structure with high insecticidal activity against the Australian sheep blowfly,Lucilia cuprina, was shown to have a higher activity as an uncoupler of oxidative phosphorylation in insect compared to mammalian mitochondrial preparations. This compound possesses the requirements of other uncouplers in its measured pKa and lipid solubility. However, when compared to a closely related structure with similar physicochemical properties, its insecticidal and insect mitochondrial uncoupling activities are greater and it exhibits decreased mammalian toxicity corresponding to this differential biochemical selectivity.Acknowledgment. We thank Mr K. Rihs for preparation of the hydrazones and Prof. Dr K.H. Büchel for supply of hydrazone III.