Theoretical insights and design of Ru(II)-based complexes with DNA-photocleavage properties

Ligand Characterization and DNA Intercalation of Ru(II) Polypyridyl Complexes: A Local Vibrational Mode Study

“…27,28 Such a measure is provided by the local vibrational stretching force constants derived from our Local Vibrational Mode Theory, 29,30 which we've applied in this study to a set of 12 representative ruthenium(II) polypyridyl complexes shown in Figure 1. 27,31,32 Complex 1 was obtained from the PDB structure of intercalated Ru(II)−DNA complex (PDB: 3U38). 33 Complexes 2−5 were motivated by the prior work of Elgar et al 31 and were selected to assess how changes in the ASL, with identical MSLs, cause changes in the strengths of the RuN ligand bonds.…”

“…Onset by the discovery that [Ru­(bpy) 2 (dppz)] 2+ (bpy = 2,2′-bipyridine, dppz = dipyrido­[3,2- a :2′,3′-c]­phenazine) binds to DNA with high affinity with an accompanying increase in MLCT luminescence, the so-called DNA light switch effect, a variety of ruthenium­(II) polypyridyl complexes with different intercalating ligands have been developed as high-affinity DNA binders. , In order to fine-tune these ruthenium­(II) polypyridyl complexes via systematic ligand modifications, one must analyze Ru-ligand bonding and the strength of the bonds with a qualified measure of bond strength. Thus, a reliable measure of the strength of DNA intercalation is needed in the case of Ru­(II) polypyridyl complexes acting as π–π stacking agents. , Such a measure is provided by the local vibrational stretching force constants derived from our Local Vibrational Mode Theory, , which we’ve applied in this study to a set of 12 representative ruthenium­(II) polypyridyl complexes shown in Figure . ,, …”

“…Complexes 6 – 10 were motivated by the prior work of Miao et al [Ru­(bpy) 2 (PIP)] 2+ ( 6 ) displays a (PIP) MSL and an ASL composed of (bpy) 2 , mimicking the substitution pattern of 2 . [Ru­(dmb) 2 (PRIP)] 2+ ( 7 ), [Ru­(phen) 2 (PRIP)]] 2+ ( 8 ), and [Ru­(dcp) 2 (PRIP)] 2+ ( 9 ) (dcp = 4,7-dicarbonitrile-1,10-phenanthroline) were chosen to simultaneously compare how modifying ASLs with unique (PRIP) MSLs changes the bond strengths of RuN ligand bonds.…”