RESUMO

The aim to access linked tetravanadate [V4O12]4- anion with mixed copper(II) complexes, using α-amino acids and phenanthroline-derived ligands, resulted in the formation of four copper(II) complexes [Cu(dmb)(Gly)(OH2)]2[Cu(dmb)(Gly)]2[V4O12]·9H2O (1) [Cu(dmb)(Lys)]2[V4O12]·8H2O (2), [Cu(dmp)2][V4O12]·C2H5OH·11H2O (3), and [Cu(dmp)(Gly)Cl]·2H2O (4), where dmb = 4,4'-dimethioxy-2,2'-bipyridine; Gly = glycine; Lys = lysine; and dmp = 2,9-dimethyl-1,10-phenanthroline. The [V4O12]4- anion is functionalized with mixed copper(II) units in 1 and 2; while in 3, it acts as a counterion of two [Cu(dmp)]2+ units. Compound 4 crystallized as a unit that did not incorporate the vanadium cluster. All compounds present magnetic couplings arising from Cu⋯O/Cu⋯Cu bridges. Stability studies of water-soluble 3 and 4 by UV-Vis spectroscopy in cell culture medium confirmed the robustness of 3, while 4 appears to undergo ligand scrambling over time, resulting partially in the stable species [Cu(dmp)2]+ that was also identified by electrospray ionization mass spectrometry at m/z = 479. The in vitro cytotoxicity activity of 3 and 4 was determined in six cancer cell lines; the healthy cell line COS-7 was also included for comparative purposes. MCF-7 cells were more sensitive to compound 3 with an IC50 value of 12 ± 1.2 nmol. The tested compounds did not show lipid peroxidation in the TBARS assay, ruling out a mechanism of action via reactive oxygen species formation. Both compounds inhibited cell migration at 5 µM in wound-healing assays using MCF-7, PC-3, and SKLU-1 cell lines, opening a new window to study the anti-metastatic effect of mixed vanadium-copper(II) systems.

Assuntos

Antineoplásicos , Complexos de Coordenação , Humanos , Cobre/farmacologia , Cobre/química , Antineoplásicos/química , Fenantrolinas/química , Vanádio/farmacologia , DNA/química , Células MCF-7 , Ânions , Fenômenos Magnéticos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Ligantes

RESUMO

The synthesis and theoretical-experimental characterization of a novel diprotanated decavanadate is presented here due to our search for novel anticancer metallodrugs. Tris(2-pyridylmethyl)amine (TPMA), which is also known to have anticancer activity in osteosarcoma cell lines, was introduced as a possible cationic species that could act as a counterpart for the decavanadate anion. However, the isolated compound contains the previously reported vanadium (V) dioxido-tpma moieties, and the decavanadate anion appears to be diprotonated. The structural characterization of the compound was performed by infrared spectroscopy and single-crystal X-ray diffraction. In addition, DFT calculations were used to analyze the reactive sites involved in the donor-acceptor interactions from the molecular electrostatic potential maps. The level of theory mPW1PW91/6-31G(d)-LANL2DZ and ECP = LANL2DZ for the V atom was used. These insights about the compounds' main interactions were supported by analyzing the noncovalent interactions utilizing the AIM and Hirshfeld surfaces approach. Molecular docking studies with small RNA fragments were used to assess the hypothesis that decavanadate's anticancer activity could be attributed to its interaction with lncRNA molecules. Thus, a combination of three potentially beneficial components could be evaluated in various cancer cell lines.

RESUMO

A new coordination mode for the hybrid scorpionate/cyclopentadienyl ligand bpzcp, [bpzcp = 2,2-bis(3,5-dimethylpyrazol-1-yl)-1,1-diphenylethylcyclopentadienyl] is observed in iridium complexes. The reaction of the lithium precursor, [Li(bpzcp)(THF)], with a range of [IrCl(diene)]2 compounds leads to an unprecedented binding mode of the hybrid scorpionate/cyclopentadienyl ligand as η5-Cp-coordinated and the formation of Ir(I) derivatives [Ir(η5-Cp-bpzcp)(η4-cod)] (1), [Ir(η5-Cp-bpzcp){η4-CH2═C(Me)C(Me)═CH2}] (2), [Ir(η5-Cp-bpzcp)(η2-coe)2] (3), and [Ir(η5-Cp-bpzcp)(η2-CH2═CH2)2] (4). The Ir(I) complex 4 reacts with CO or bromine to afford the compound [Ir(η5-Cp-bpzcp)(CO)2] (5) and the 18e- Ir(III) complex [Ir(κ-N-η5-Cp-bpzcpBr2)Br2] (6), respectively. Reaction of the iridium compounds (2-4) with CuI or [PdCl2(CH3CN)2] yields the heterobimetallic iridium-copper or iridium-palladium complexes [Ir(η5-Cp-bpzcp){η4-CH2═C(Me)C(Me)═CH2}(µ-bpzcp){CuI(κ2-NN-bpzcp)}] (7), [Ir(η5-Cp-bpzcp)(η2-coe)2}(µ-bpzcp){CuI(κ2-NN-bpzcp)}] (8), [Ir(η5-Cp-bpzcp)(η2-CH2═CH2)2}(µ-bpzcp){CuI(κ2-NN-bpzcp)}] (9), [Ir(η5-Cp-bpzcp)(coe)2}(µ-bpzcp){PdCl2(κ2-NN-bpzcp)}] (10), and [Ir(η5-Cp-bpzcp)(η2-CH2═CH2)2(µ-bpzcp){PdCl2(κ2-NN-bpzcp)}] (11). All products were characterized by spectroscopic methods and the X-ray crystal structures of 1, 2, 3, 4, and 6 were also established.

RESUMO

The hydrothermal reaction of 2-pyrimidine-carboxamide, CoCl2.6H(2)O and K3[Co(CN)6] affords a novel mixed-valence Co(II)/Co(III) 3D complex K[Co3(CN)6(ox)(H(2)O)2].H2O, which contains cyano-bridged Co(7) defective cubanes connected by oxalate and cyanide bridging groups and behaves as a canted antiferromagnet with Tc = 17.5 K.