RESUMEN
In this paper, we present the synthesis of four new complexes: the dimeric precursor [Ir(dmppz)2(µ-Cl)]2 (1) (Hdmppz - 3,5-dimethyl-1-phenyl-1H-pyrazole) and heteroleptic bis-cyclometalated complexes: [Ir(dmppz)2(Py2CO)]PF6·½CH2Cl2 (2), [Ir(dmppz)2(H2biim)]PF6·H2O (3), and [Ir(dmppz)2(PyBIm)]PF6 (4), with auxiliary N,N-donor ligands: 2-di(pyridyl)ketone (Py2CO), 2,2'-biimidazole (H2biim) and 2-(2'-pyridyl)benzimidazole (PyBIm). In the obtained complexes, SC-X-ray analysis revealed that Ir(III) has an octahedral coordination sphere with chromophores of the type {IrN2C2Cl2} (1) or {IrN4C2} (2-4). The complexes obtained, which have been fully characterised by physicochemical methods (CHN, TG, FTIR, UV-Vis, PL and 1H, 13C, 15N NMR), were used to continue our studies on the factors influencing the cytotoxic properties of potential chemotherapeutic agents (in vitro). To this end, the following studies are presented: (i) comparative analysis of the effects on the biological properties of N,N-donor ligands and C,N-donor ligands in the studied complexes, (ii) studies of the interactions of the compounds with the selected molecular target: DNA and BSA (UV-Vis, CD and PL methods), (iii) and the reactivity towards redox molecules: GSH, NADH (UV-Vis and/or ESI-MS methods), (iv) cytotoxic activity (IC50) of potential chemotherapeutics against MCF-7, K-562 and CCRF-CEM cell lines.
Asunto(s)
Antineoplásicos , Proliferación Celular , Complejos de Coordinación , Iridio , Pirazoles , Pirazoles/química , Pirazoles/farmacología , Pirazoles/síntesis química , Humanos , Ligandos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Iridio/química , Iridio/farmacología , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Teoría Cuántica , ADN/química , ADN/metabolismo , Estructura Molecular , Modelos Moleculares , Procesos FotoquímicosRESUMEN
To evaluate the antioxidant activity of potential synthetic enzyme mimetics, we prepared new five copper(II) complexes via a self-assembly method and named them [Cu(2-(HOCH2)py)3](ClO4)2 (1), [Cu(2-(HOCH2)py)2(H2O)2]SiF6 (2), [Cu2(2-(HOCH2CH2)py)2(2-(OCH2CH2)py)2](ClO4)2 (3), [Cu(pyBIm)3](BF4)2·1.5H2O (4) and [Cu(py2C(OH)2)2](ClO4)2 (5). The synthetic protocol involved N,O- or N,N-donors: 2-(hydroxymethyl)pyridine (2-(HOCH2)py), 2-(hydroxyethyl)pyridine (2-(HOCH2CH2)py), 2-(2-pyridyl)benzimidazole (pyBIm), di(2-pyridyl)ketone (py2CO). The obtained Cu(II) complexes were fully characterised by elemental analysis, FTIR, EPR, UV-Vis, single-crystal X-ray diffraction and Hirshfeld surface analysis. Crystallographic and spectroscopic analyses confirmed chromophores of both monomeric ({CuN3O3} (1), {CuN2O4} (2), {CuN6} (4), {CuN4O2} (5)) and dimeric complex ({CuN2O3} (3)). Most of the obtained species possessed a distorted octahedral environment, except dimer 3, which consisted of two copper centres with square pyramidal geometries. The water-soluble compounds (1, 3 and 5) were selected for biological testing. The results of the study revealed that complex 1 in solutions displayed better radical scavenging activity than complexes 3, 5 and free ligands. Therefore, complex 1 has been selected for further studies to test its activity as an enzyme mimetic. The chosen compound was tested on the erythrocyte lysate of two groups of patients after undergoing chemotherapy and chemoradiotherapy. The effect of the tested compound (1) on enzyme activity levels (TAS, SOD and CAT) suggests that the selected complex can be treated as a functional mimetic of the enzymes.