Reaction of the antithrombotic and antimetastatic agent, nafazatrom, with oxidizing radicals

Pulse radiolysis and electron spin resonance experiments have been performed on the antithrombotic and antimetastatic agent, nafazatrom. Results show that nafazatrom is an extremely reactive scavenger of free radicals. The rate of its reaction with Br-2 is higher than rates found for biologically important antioxidants, tocopherol and ascorbate. The radical formed by oxidation of nafazatrom is indicated by ESR to have a structure similar to phenoxyl radical. This radical is found to decay at a rate approaching diffusion controlled rates. The ease of oxidation of nafazatrom makes it ideally suited to act as an antioxidant. This property may be an important determinant of its pharmacological activities.