A P-31 NMR-STUDY OF THE INTERACTION OF THE ANTITUMOR ACTIVE METALLOCENE CP2MOCL2 WITH CALF THYMUS DNA

Treatment of sonicated calf thymus DNA with the antitumor active metal locene Cp2MoCl2 afforded a metallocene-DNA complex which was character ized by P-31 NMR spectroscopy. In addition to the resonance for the ph osphate backbone (delta-1.6), the spectrum contained 2 signals assigne d to a phosphate bound Mo-DNA complex(es) (delta 37.2, 36.5) and a bro ad signal at delta 6.2 ppm. This result suggests that covalent attachm ent of the metallocene CP2MoCl2 occurs via phosphate(O) coordination a nd is accompanied by local distortion of the DNA backbone. This result supports recent ICP studies with Cp2TiCl2 that have DNA detected DNA- metallocene adducts.