One-electron oxidation occurred simultaneously on the formation of copper (II), ferric(II) or oxovanadium(II) complexes with oximes and related compounds produces iminoxy radicals. These iminoxy radicals are stable in complexes with metal ions but change into another radical which produced by Beckmann rearrangement reaction of oxime under acidic condition. These results reflect that reactivity of oximes and aldoximes are affected by molecular structure and oxide or metal ion Behavior of radicals produced in the reaction such as Beckmann rearrangement is suggested to be involved in the similar mechanism detected in metabolism.