DNA-binding of semirigid binuclear ruthenium complex Δ, Δ-[μ-(11,11'-bidppz)(phen)4Ru2]4+: Extremely slow intercalation kinetics

摘要: We here report a remarkably slow rearrangement of binding modes for binuclear ruthenium(II) complex upon interaction with DNA. It has been previously shown that Δ,Δ-[μ-(11,11‘-bidppz)(phen)4Ru2]4+ binds to DNA in one the grooves. However, we find this is only an initial, metastable, mode, which extremely slowly reorganized into intercalative geometry. The and dissociation, revealed by flow linear dichroism fluorescence spectroscopy, are concluded be result from being threaded through DNA, bridging aromatic dppz ligands intercalated between base pairs placing metal center minor groove major groove. A negative LD, high luminescence quantum yield, long lifetimes, similar intercalating Δ-[Ru(phen)2dppz]2+, indicate intercalation bidppz moiety. unique dissociation its final DNA-binding mode suggests cl...