Substituted α-(phenylhydrazono)phenylacetonitrile derivatives. Part 1: A new class of uncoupler of oxidative phosphorylation

Substituted α‐(phenylhydrazono)phenylacetonitrile derivatives have been discovered which constitute a series of potent uncouplers of oxidative phosphorylation. Systematic variation of substituents on both benzene rings has clearly demonstrated the importance of steric congestion around the ionisation site and delocalisation of negative charge in the anionic form. Replacement of the cyano group by other electron‐withdrawing groups leads to a dramatic decrease in uncoupling activity. The sub‐nanomolar levels of uncoupling activity found in certain members indicate that these compounds are the most potent uncouplers yet reported. Copyright © 2006 Society of Chemical Industry