The current article reports the investigation of three new Ni(II) complexes with ONS-donor dithiocarbazate ligands: Ni(L1)PPh3 (1), Ni(L2)PPh3 (2), and Ni(L2)Py (3). Single-crystal X-ray analyses ...revealed mononuclear complexes with a distorted square planar geometry and the metal centers coordinated with a doubly deprotonated dithiocarbazate ligand and coligand pyridine or triphenylphosphine. The non-covalent interactions were investigated by the Hirshfeld surface and the results revealed that the strongest interactions were π⋅⋅⋅π stacking interactions and non-classical hydrogen bonds C–H···H and C–H···N. Physicochemical and spectroscopic methods indicate the same structures in the solid state and solution. The toxicity effects of the free ligands and Ni(II) complexes were tested on the human breast cancer cell line MCF-7 and non-malignant breast epithelial cell line MCF-10A. The half-maximal inhibitory concentration (IC50) values, indicating that the compounds were potent in inhibiting cell growth, were obtained for both cell lines at three distinct time points. While inhibitory effects were evident in both malignant and non-malignant cells, all three complexes demonstrated lower IC50 values for malignant breast cell lines than their non-malignant counterparts, suggesting a stronger impact on cancerous cell lines. Furthermore, molecular docking studies were performed showing the complex (2) as a promising candidate for further therapeutic exploration.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The present work reports the synthesis and a structural study of two novel dithiocarbazate, the 4,6-diacetylresorcinol-S-benzyldithiocarbazate (H3L1) and the ...4,6-diacetylresorcinol-bis(S-benzyldithiocarbazate) (H4L2), and their Ni(II) complexes, Ni(HL1)(Py) (1) and Ni2(L2)(PPh3)2 (2). Single crystal X-ray analyzes reveal mono and binuclear complexes and the metal centers with distorted square planar geometry. The analyses of the Hirshfeld surface and fingerprints plots revealed intermolecular contacts attributed to the H···H and C···H/H···C bonds. The Density Functional Theory (DFT), with the B3LYP functional and 6–311-G(d,p)/LanL2DZ basis sets, was employed to optimize the geometries of synthesized compounds. From the resulting geometries, the highest occupied and lowest unoccupied molecular orbital maps (HOMO-LUMO), orbital energy gap, electron localization function (ELF), electron density, natural bond orbital (NBO) analysis, and complexation of the ligands with Ni(II) were calculated supporting the experimental data. The ESI (+)-MS/MS data indicated the presence in solution of the characteristic fragmentation with the H3L1+ and H4L2+ molecular ions for the ligands. The pharmacological potential of the dithiocarbazate ligands and their Ni(II) complexes were evaluated in vitro against MDA-MB-231 human breast cancer cells. A remarkable cytotoxic activity was observed, more evident for free ligands than complexes at low concentrations; however, this latter showed a better dose–response pattern, being more attractive in terms of pharmacokinetics and therapeutic window.
Two new Ni(II) complexes with symmetrical and asymmetrical 4,6-diacetylresorcinol-dithiocarbazate ligands were synthesized and showed remarkable cytotoxic activity against MDA-MB-231 human breast cancer cells. Display omitted
•Two new Ni(II) complexes were studied by X-ray crystallography.•Symmetrical and asymmetrical 4,6-diacetylresorcinol-dithiocarbazate were synthesized.•The theoretical calculation and Hirshfeld surface were investigated.•The pharmacological potential was evaluated in vitro against MDA-MB-231 cells.•The biological analysis shows an interesting dose–response curve profile.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Dimeric Cu(II) complexes and dithiocarbazate ligands were successfully synthesized.•New molecular structures were confirmed by single crystal X-ray diffraction.•Antibacterial and ...antifungal properties were performed.
The current work reports the synthesis and crystals structure of two copper(II) complexes (CuL1)2 (1) and (CuL2)2 (2), with S-allyl-2-(2-hydroxyphenyl-ethylidene)dithiocarbazato and S-benzyl-2-(2-hydroxyphenyl-ethylidene) dithiocarbazato (H2L1 and H2L2, respectively). The single-crystal X-ray analyses reveal dimeric structures of the complexes with a distorted square planar coordination geometry. The phenoxo bridging mode observed in these complexes is located between the two copper atoms with ONS-donor ligands. The crystal packings are stabilized by hydrogen bonds involving the adjacent molecules. The compounds were also characterized by physicochemical and spectroscopic methods. The antibacterial and antifungal properties of the free dithiocarbazates and its Cu(II) complexes have been evaluated against several multiresistant bacteria and fungi. In all experiments, a superior antimicrobial activity of the complexes was observed compared to the free ligands.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The present work reports the synthesis and structural elucidation of six novel copper(II) complexes with 2-acetylpyridine semicarbazone (HL
1
) and 2-acetylpyridine
N
(4)-phenyl semicarbazone (HL
2
...). In all compounds, the semicarbazone ligands were find tridentate with
NNO
-donor atoms. The single crystal X-ray diffraction analysis showed the influences of the different copper salt starting reagent in the crystal structures. A packing architectures analysis has been undertaken to delineate the role of relevant noncovalent interactions. The π···π stacking interactions and hydrogen bonds were analyzed using the Hirshfeld surface and fingerprint plots. In addition, the compounds were also characterized by physicochemical and spectroscopic methods.
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A new ligand and six copper(II) complexes of semicarbazone derivatives have been synthesized and their crystal structures have been studied. Spectroscopy experiments and Hirshfeld Surface were analyzed.
•Lithium and sodium niobate nanoparticles synthesized for the first time by microwave-assisted combustion.•23Na and 93Nb solid state NMR could identify the presence of Pbma and P21ma polymorphs of ...NaNbO3.•The synthesized niobate nanoparticles show catalytic activity for the degradation of methylene blue dye, comparable to materials synthesized by conventional methods.
Nanoparticles of LiNbO3 and NaNbO3 were obtained for the first time by microwave-assisted combustion. Preliminary experiments reveal that the synthetic conditions influence their microstructure and optoelectronic features. Therefore, there is a need for performing the structural characterization of these materials, obtained by this new route. In the case of NaNbO3, there are two polimorphs which are stable at room temperature, space groups P21ma and Pbma. Powder x-Ray diffraction experiments were not capable to identify the crystalline phases present in the nanoparticles. Therefore, we have performed a detailed structural characterization of the nanoparticles by 1D and 2D solid state 23Na and 93Nb Nuclear Magnetic Resonance (NMR) techniques. 23Na results reveal the presence of both phases, Pbma and P21ma, for samples prepared using NaNO3 precursor in a 1:1 Na:Nb ratio or NaCl in excess. On the other hand, the P21ma polymorph could be isolated in the synthesis using NaCl salt in 1:1 Na:Nb ratio. On the other hand, LiNbO3 nanoparticles display the usual rhombohedral structure R3c. 7Li MAS NMR results reveal the presence of two types of Li species, with distinct dynamics. Highly mobile Li+ ions are found at the surface of the nanoparticles, while bulk Li+ show restricted movement. Finally, as a proof of principle, the photocatalytic activity of these niobates was tested for the degradation of methylene blue dye, a common organic-water contaminant.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The present work reports the synthesis and structural elucidation of two dithiocarbazate ligands derived from 4,6-diacetylresorcinol (H3L1) and (H3L2) and two Cu(II) complexes, Cu(μ-HL1)2 (1) and ...Cu(μ-HL2)2 (2). These compounds were studied by the Density Functional Theory with which it was possible to identify their lowest energy conformations. With the optimized configurations, the UV–vis, HOMO, LUMO and gap properties were determined and compared with the experimental data. Energy calculations for the compounds were useful to determine binding sites and predicting the reactivity of the compounds. The experiment ESI (+) - MS/MS revealed dinuclear structures of the complexes. The set of spectroscopic analysis agreed with the proposed theoretical structures. The antitumor activity and selectivity of free dithiocarbazates and their Cu(II) complexes were evaluated against MCF-7, PBMC and healthy cells. In all tests, a higher activity of the complexes over free ligands was observed, which agrees with the predicted theory.
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•Two ligands of 4,6-diacetylresorcinol-dithiocarbazates and their copper(II) complexes were prepared.•The compounds were fully characterized and investigated by DFT calculations.•The geometry elucidates of the complexes shows dinuclear coordinations compounds.•The antitumor activity and selectivity was evaluated against MCF-7, PBMC and healthy cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Depending on its nature, particulate matter has very different size, composition and morphology. By the combination of these criteria it is possible to distinguish the emitting sources (primary or ...secondary). The shape and the dimension of the particles have also a direct interaction with the risk assessment for human health. The minero-chemical complex consists of phosphate fertilizer manufacturing, rock phosphate and niobium mining open pits and it is located northeast of the urban area of the city. Environmental issues associated with it include the following: fugitive emissions which are primarily associated with operational leaks from tubing, valves, connections, flanges, packings, open ended lines, floating roof storage tank and pump seals, gas conveyance systems, compressor seals, pressure relief valves, tanks or open its/containments, and loading and unloading operations of products. Furthermore the area of study is characterized by a predominantly northeast winds direction. The monitoring was performed weekly particulates samples were collected in two seasonal episodes at one representative places in the urban area of Catalão (a Brazilian city located in Goiás state) in the period from August to November of 2014. Suspended particles were sampled on pure fiberglass filters by using a High Volume air sampler and were analyzed via an energy dispersive X-ray microanalysis system (EDX). The airborne particulate matter was characterized from a physico-chemical point of view to supply information on the particle composition and the compounds carried on their surfaces. The microanalysis enables identification of several groups of particles such as: soot, Si-rich, metal-rich and biological particules. These results may help in controlling and preventing fugitive emissions in atmospheric air.
