RESUMO
Three new tripod tetradentate phenolate-amines (H2L1, H2L4 and H2L9), together with seven more already related published ligands, were synthesized, and characterized. With these ligands, two new dinuclear doubly-bridged-phenoxido copper(II) complexes (3, 4), and six more complexes (1, 2, 5-8), a new trinuclear complex (9) with an alternative doubly-bridged-phenoxido and -methoxido, as well as the 1D polymer (10) were synthesized, and their molecular structures were characterized by spectroscopic methods and X-ray single crystal crystallography. The Cu(II) centers in these complexes exhibit distorted square-pyramidal arrangement in 1-4, mixed square pyramidal and square planar in 5, 6, and 9, and distorted octahedral (5+1) arrangements in 7 and 8. The temperature dependence magnetic susceptibility study over the temperature range 2-300 K revealed moderate-relatively strong antiferromagnetic coupling (AF) (|J| = 289-145 cm-1) in complexes 1-6, weak-moderate AF (|J| = 59 cm-1) in the trinuclear complex 9, but weak AF interactions (|J| = 3.6 & 4.6 cm-1) were obtained in 7 and 8. No correlation was found between the exchange coupling J and the geometrical structural parameters of the four-membered Cu2O2 rings.
RESUMO
Two cationic [Cu2(L1-2)2](ClO4)2 (1, 2), and four neutral doubly bridged-phenoxido-copper(II) complexes [Cu2(L3-4)2] (3, 4) and [Cu2(L5-6)2(H2O)]â§2H2O (5, 6) as well as 1D polymeric catena-[Cu(L7)] (7), where HL1-2 and H2L3-7 represent tripodal tetradentate pyridyl or aliphatic-amino groups based 2,4-disubstituted phenolates, were synthesized and thoroughly characterized by various spectroscopic methods and single crystal X-ray analysis. The molecular structures of the complexes exhibited diverse geometrical environments around the central Cu(II) atoms. The in vitro antiproliferative activity of the isolated complexes and selected parent free ligands were screened against some human cancer cell lines (A2780, A2780R, PC-3, 22Rv1, MCF-7). The most promising cytotoxicity against cancer cells were obtained for 1-6, while complex 6 was found as the best performing as compared to the reference drug cisplatin. The cytotoxicity study of complex 6 was therefore extended to wider variety of cancer cell lines (HOS, A549, PANC-1, CaCo2, HeLa) and results revealed its significant cytotoxicity on all investigated human cancer cells. The cell uptake study showed that cytotoxicity of 6 (3 µM concentration and 24 h of incubation) against A2780 cells was almost independent from the intracellular levels of copper. The effect of complexes 4, 6 and 7 on cell cycle of A2780 cells indicates that the mechanism of action in these complexes is not only different from that of cisplatin but also different among them. Complex 7 was able to induce apoptosis in A2780 cells, while complexes 4 and 6 did not and on the other hand, they showed considerable effect on autophagy induction and there are some clues that these complexes were able to induce cuproptosis in A2780 cells.