1H-NMR Study of Ternary Platinum(II) Complexes with N-(1-Naphtyl)methyl-1,2-ethanediamine or N-(9-Anthrylmethyl)-1,2-ethanediamine and Bipyridine or Phenanthroline and Restricted Single Bond Rotation Due to Aromatic-Aromatic Ring Interaction

Abstract

2؉ complex showed an activation energy of ca. kJ mol ؊1, which is in good agreement with a mechanism involving successive rotations about single bonds with restriction by intramolecular aromatic-aromatic ring interactions.

Characterization of platinum(II) complexes exhibiting inhibitory activity against the 20S proteasome

“…We previously synthesized complex 1 and determined its X-ray crystal structure [ 33 ]. Complexes 2 , 3 , 6 and 7 were designed as model systems of the interaction between cis -diamminedichloroplatinum (II) and DNA, and the physico-chemical properties were determined [ 34 – 36 ]. We performed screening assays of the proteasome-inhibitory activity of new and reported platinum complexes.…”

“…These results suggested that the electronic state of the platinum coordination plane differs between complexes 1 and 2 . Complexes 1 and 2 exhibited a stacking interaction between ligands [ 33 , 36 ], and the stability of the stack is assumed to be correlated with the surface area of the aromatic rings. There is the possibility that stacking interaction between phenanthroline and anthracenyl moiety induced electron withdrawal from the platinum atom to phenanthroline [ 55 ].…”