Synthesis, Biological Evaluation, and Molecular Docking Studies on the DNA Binding Interactions of Platinum(II) Rollover Complexes Containing Phosphorus Donor Ligands.

Cyclometalated rollover complexes of the type [PtMe(κ N,C-bipyO-H)(L)] [bipyO-H=cyclometalated 2,2'-bipyridine N-oxide; L=tricyclohexylphosphine (PCy , 2 a), 2-(diphenylphosphino)pyridine (PPh py, 2 b), P(OPh) (2 c)] were synthesized by treating [PtMe(κ N,C-bipyO-H)(SMe )] (1) with various monodentate phosphine and phosphite ligands. These complexes were characterized by NMR spectroscopy, and the structure of 2 a was confirmed by single-crystal X-ray diffraction. Complex 1 was treated with bis(diphenylphosphino)methane (dppm) at a 1:1 ratio to give the corresponding [PtMe(κ N,C-bipyO-H)(κ P-dppm)] (3 b) complex, in which the dppm ligand acts as a monodentate pendant ligand.