RESUMO

Five ternary copper(II) complexes, [Cu2(phen)2(L1)(ClO4)2] (1), [Cu2(phen)2(L1)(DMSO)2](PF6)2 (2), [Cu2(bpy)2(L1)(ClO4)2(H2O)2] (3), [Cu2(dmp)2(L1)(ClO4)2(H2O)2] (4), and [Cu(phen)(L2)]2(ClO4)2 (5), in which phen = 1,10-phenanthroline, bpy = 2,2'-bipyridine, dmp = 2,9-dimethyl-1,10-phenanthroline, H2L1 = 1,4-dihydroxyanthracene-9,10-dione and HL2 = 1-hydroxyanthracene-9,10-dione, DMSO = dimethylsulfoxide, were synthesized and fully characterized. Complex 2 was obtained through the substitution of perchlorate for DMSO. When two hydroxyquinone groups are present, L1 makes a bridge between two Cu(II) ions, which also bind two nitrogens of the respective diimine ligand. The compounds bind to calf thymus DNA and oxidatively cleave pUC19 DNA according to the following order of activity 1 > 4-5 > 3. Furthermore, complexes 1, 3, 4 and 5 inhibit topoisomerase-I activity and the growth of myelogenous leukemia cells with the IC50 values of 1.13, 10.60, 0.078, and 1.84 µmol L-1, respectively. Complexes 1 and 4 are the most active in cancer cells and in DNA cleavage.

Assuntos

Cobre , Compostos Heterocíclicos , Cobre/farmacologia , Ligantes , Dimetil Sulfóxido , Ligação Proteica , Cristalografia por Raios X

RESUMO

A series of semicrystalline and amorphous one-dimensional (1D) polymeric chains consisting of cubane-like CoII4L4 units (L = S-1,2-bis(benzimidazol-2-yl)ethanol) and dicarboxylates were synthesized and characterized by single crystal diffraction and X-ray total scattering. The polycationic chains are composed of [Co4L4(dicarboxylate)]2+ monomeric units, while one molecular dicarboxylate counterion is balancing the charge of each monomer. The linear compound series has five members, and the crystal structures were solved for [Co4L4(tph)](tph) and [Co4L4(ndc)](ndc), where tph = terephthalate and ndc = 2,6-naphthalenedicarboxylate. Partly crystalline compounds were produced by slow assembly at elevated temperature (over days), while the amorphous compounds were formed by fast precipitation (within minutes). Pair distribution function (PDF) analysis based on X-ray total scattering data reveals the presence of the cubane-like entity in both the amorphous and semicrystalline samples. While the powders are non-porous, precipitation is a fast and versatile method to produce compounds with cubane-like centres with moderate surface areas of 17-49 m2 g-1 allowing for surface chemical reactions. The powders have a high concentration of Lewis base sites as verified by their selective adsorption of CO2 over N2. The use of an amorphous cubane-like polymer for the electrocatalytic oxygen evolution reaction was demonstrated.