Development of a DNA-damaging ferrocene amino acid

The oxygen-sensitive ferrocenylacetic acid moiety was incorporated in a water-soluble DNA-damaging agent via the synthon 1,1′-ferrocenediacetic acid anhydride. The extent of plasmid nicking was pH-dependent, with complete cleavage at pH 5.5. The nicking was indiscriminate and required O2, implicating reduced oxygen species as the actual damaging agent.