Unique structural properties of DNA interstrand cross-links formed by a new antitumor dinuclear Pt(ii) complex.

The DNA interstrand cross-links of the antitumor drug {[cis-Pt(NH3)(2)Cl](2)(4,4'-methylenedianiline)}(2+) (1) play a prevalent role in its antitumor effects. Complex 1 forms DNA long-range interstrand cross-links uniquely in the 3'-3' direction. Conformational distortions induced by these interstrand cross-links in DNA represent a potential structural motif for recognition by high-mobility-group proteins.