Studies of Pyridinyl‐Containing 14‐Membered Macrocyclic Copper(II) Complexes

Abstract

Six copper(II) complexes of tetracoordinating, pyridinyl-containing 14-membered macrocycles with varying ratios of nitrogen and oxygen donor atoms were prepared and characterized by IR, UV/Vis, and EPR spectroscopy and cyclic voltammetry. A distorted tetragonal coordination of the copper center in the solid-state was established by X-ray crystallography for the tetraazamacrocyclic complex Cu-3 carrying a methoxybenzyl pendent arm and the trioxaaza complex Cu-6. The superoxide dismutase-like activity of the Cu II complexes was investigated by inhibition of NADH oxidation. Al-

Macrocyclic copper(II) complexes: Superoxide scavenging activity, structural studies and cytotoxicity evaluation

“…some Mn-salens and Mn-porphyrins) have also been described [43,46,47], despite some of them are not readily water soluble. Nevertheless, focusing on the previously reported macrocyclic copper(II) complexes, which are more similar to the presented compounds, it is noticeable that the complexes under study are generally more active, having lower IC 50 values [7,10].…”

“…Transition metal complexes [e.g. complexes of Mn(II), Mn(III), Cu(II) and Fe(III)] have notably shown important antioxidant properties, namely SOD mimetic activity [6,7]. The metal containing SOD mimetic agents more extensively studied are manganese(III) metalloporphyrins, manganese(III) salen complexes and manganese(II) macrocyclic complexes [1].…”

“…The macrocyclic nature of the ligand seems important for the SOD mimetic activity of the corresponding complexes as well as for their stability in the presence of proteins, even if the metal ion does not lie inside the cavity [8]. Several macrocyclic copper complexes have been reported to scavenge the superoxide anion [7][8][9][10][11].…”

Speciation study of an imidazolate-bridged copper(II)–zinc(II) complex in aqueous solution

“…Thus, many SOD mimicking metal complexes were investigated in the past years. Several mononuclear copper(II) complexes were synthesised, and their magnetic behaviour, solution properties and reduction features were reported [4][5][6][7][8][9][10][11][12][13]. Their SOD activities have also been investigated by various SOD assays.…”

Methoxy VO–salen Stimulates Pancreatic β Cell Survival by Upregulation of eNOS and Downregulation of Apoptosis in STZ-induced Diabetic Rats

“…Due to extensive deleterious effect of ROS on structural and functional integrities of biological systems, a great deal of scientific efforts has been devoted to finding the effective free radical scavengers, which are referred to as antioxidants. In this respect, transition metal complexes have notably shown to possess high antioxidant properties [7,8]. From this group of compounds, vanadium complexes deserve special attention.…”