Preparation, characterization and crystal structures of manganese(II), iron(III) and copper(II) complexes of the bi.
The synthesis of a new tetrapyridyl ligand, bis[di-1,1-(2-pyridyl)ethyl]amine (BDPEA), is described. Complexation of this ligand with manganese(II), iron(III) or copper(II) chlorides afforded mononuclear complexes: Mn(BDPEA)Cl2 (1) [Fe (BDPEA)Cl2]Cl (2) and [Cu(BDPEA)Cl]Cl (3). In all cases, BDPEA is coordinated to the metal center by three pyridine nitrogen atoms and the secondary amine. The geometrical environments around the metals in Mn(BDPEA)Cl2 and [Fe(BDPEA)Cl2]Cl are best described as distorted octahedrals and in [Cu (BDPEA)Cl]Cl as a slightly distorted square pyramid. The DNA cleavage activities of manganese(II), iron (III) or copper(II) complexes of both BDPEA and another tetrapyridyl ligand, bis[di(2-pyridyl) methyl]amine (BDPMA), in the presence of an oxidant (H2O2) or a reducing agent (ascorbate) with air, are reported. The iron(III) complexes exhibited significantly enhanced efficiencies, compared to copper(II) complexes. [Fe(BDPEA)Cl2]Cl is found to be the most active DNA cleaver, in agreement with a better stability of BDPEA in oxidizing conditions.
Hemmert
C
C
Laboratoire de Chimie de Coordination du CNRS, Toulouse, France.
Pitié
M
M
Renz
M
M
Gornitzka
H
H
Soulet
S
S
Meunier
B
B
D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry / Q000187:drug effects*; D005021:Ethylamines / Q000494:pharmacology*; D005069:Evaluation Studies as Topic; D006868:Hydrolysis; D007501:Iron / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008345:Manganese / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D011725:Pyridines / Q000494:pharmacology*
D005021:Ethylamines; D011725:Pyridines; C421033:bis(di-1,1-(2-pyridyl)ethyl)amine; D008345:Manganese; D003300:Copper; D004247:DNA; D007501:Iron