[Synthesis and DNA-cleaving activity of a series of substituted arenediazonium ions].

We investigated the reactions of substituted aryl radicals and aryl cations derived from arenediazonium ions and their ability to cause cleavage of supercoiled DNA and their tendency toward free radical or cation formation in the presence and absent of copper (I) chloride. It was found that the substituted arenediazonium salts can cleave supercoiled DNA to the open circular form II DNA and linear form III DNA. Results of methodical studies indicate that both carbon-centered radicals and aryl cations participate in the cleavage pathways.