Photoinduced DNA cleavage by cyclopentadienyl metal complexes conjugated to DNA recognition elements

[structure: see text]. DNA recognition elements have been attached to CpW(CO)3CH3 and CpW(CO)3Ph, which produce methyl and phenyl radicals that cleave DNA upon photolysis. The inclusion of binding moieties in 3 increases the efficiency but not the selectivity of strand scission over that seen in the simple unfunctionalized complex, while 11 cleaves preferentially at T sites within AT-rich tracts.