Tiossemicarbazonas: métodos de obtenção, aplicações sintéticas e importância biológica

Platinum(II) and palladium(II) complexes [ML 2 ] have been isolated from reaction of K 2 PtCl 4 or K 2 PdCl 4 and ligands (L) derived from thiosemicarbazones. The complexes were characterized by elemental analysis, Raman, IR, and NMR spectroscopy. In addition, quantum mechanical calculations were used to predict their structures and spectroscopic properties. For the first time, theoretical calculations using 195 Pt NMR data were used to support the suggested structures. The results indicate that the thionic sulfur and the azomethine nitrogen are bonded to the metal ion in a trans configuration. Antibacterial activities and cytotoxicities of the complexes to B16-F10 and CT26.WT cell lines were also investigated. Some of the complexes demonstrated superior cytotoxic activity compared to cisplatin.

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“…They were characterized using IR, 1 H, and 13 C NMR and by comparison with the data reported in the literature [33,34].…”

Section: Structures and Spectroscopic Characterizationmentioning

confidence: 99%

Platinum(II) and palladium(II) aryl-thiosemicarbazone complexes: synthesis, characterization, molecular modeling, cytotoxicity, and antimicrobial activity

Tavares

Paschoal

Motta

et al. 2014

Journal of Coordination Chemistry

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“…Indeed, thiosemicarbazones are able to form stable complexes with some metallic cations, such as zinc, copper and iron. 21,22 The analytical curves obtained (Figure 1b) showed a good linear range for all electrodes. However, special sensitivity was reached while using CPE/Vulcan-CBZ (0.18 µA nmol -1 L) in comparison to CPE/Vulcan (0.04 µA nmol -1 L) and unmodified CPE (0.03 µA nmol -1 L).…”

mentioning

confidence: 84%

“…19,20 This material has oxygenated surface groups that may be useful for the generation of thiosemicarbazones, which present important properties to form stable complexes with some metal cations. [21][22][23][24][25] This work describes the synthesis and application of the Vulcan-cabarzone composite (Vulcan-CBZ) for the determination of copper ions (Cu 2+ ) in complex samples, such as biodiesel, aiming to the development of a stable, sensitive and selective voltammetric sensor. Additionally, to the best of our knowledge, there is no report available that addresses the modification of Vulcan with tiosemicarbazide and its applications.…”

Section: Introductionmentioning

confidence: 99%

Development of a Novel and Simple Electroanalytical Procedure for the Determination of Copper in Biofuel Employing a Sensor Based on Vulcan Functionalized with Carbazone

Freitas¹,

Lima²,

Marques³

et al. 2018

J. Braz. Chem. Soc.

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A novel and simple electroanalytical method for the determination of Cu 2+ in biodiesel samples by stripping voltammetric analysis was developed. The method employs a carbon paste electrode (CPE) modified with Vulcan carbon, previouly functionalized with carbazone (CBZ). The CPE/Vulcan-CBZ sensor promoted a significant increase in the analytical signal obtained from copper as compared to unmodified CPE, and the CPE modified with Vulcan carbon (CPE/ Vulcan). Vulcan-CBZ, Vulcan and CBZ materials were characterized by Fourier transform infrared spectroscopy (FTIR) technique. The electrochemical behavior of the sensor was evaluated using cyclic voltammetry (CV) and square-wave anodic stripping voltammetric (SWASV) techniques. The CPE/Vulcan-CBZ modified electrode showed excellent response and was able to detect Cu 2+ at nanomolar levels. The electrochemical method is based on preconcentration of Cu 2+ ions on the CPE/Vulcan-CBZ at 0.35 V vs. Ag/AgCl(sat) in 0.2 mol L -1 ammonium sulfate solution ((NH 4 ) 2 SO 4 ), pH 3.5, during 120 s, followed by subsequent chemical stripping. The analytical signal showed a linear response for Cu 2+ concentrations in the range from 6 to 190 nmol L -1 (r = 0.998), with a detection limit of 1.2 nmol L -1 . The sensor was successfully applied for the determination of Cu 2+ in biodiesel and the average recovery varied between 97.0 and 102.8% for the soybean biodiesel samples and between 109.6 and 111.0% for the babassu biodiesel samples showing a good accuracy for the proposed method.Keywords: biofuel, copper, voltammetric sensor, Vulcan carbon, carbazone IntroductionThe pursuit of alternative fuels has been acquiring prominence in the last decades. The replacement of fossil fuels has been motivated by environmental, economical and social factors, since society itself depends on its use. In this context, one alternative that has stood out is the use of biofuels, such as charcoal, alcohol, biogas and biodiesel. 1,2 Biodiesel is a renewable fuel produced either from vegetable sources (soybean, castor oil, palm oil, sunflower, among others) or from ethanol (from sugarcane) or methanol (which can be obtained from wood biomass). 3 It is, therefore, a biodegradable, sustainable and environmentally friendly fuel. However, some metals, such as Cu, Fe, and Ni, can be inserted in the production process with the catalysts, during transportation and storage. Furthermore, the presence of these metals, even at trace levels, can promote the formation of gums and sediments that damage vehicle engines and promote the oxidation of biodiesel. 4,5 Copper, iron and the effect of nickel on biodiesel's stability has been widely evaluated. Among these metals, copper is the most powerful catalyst in biodiesel's oxidation process. 5 Therefore, the monitoring of the amount of copper is extremely important in this fuel for preventing undesirable variations in its physical state and properties, during its use or storage. 5 In this context, it is opportune and necessary to develop novel sensitive and selective anal...

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“…Therefore, TSCs and their metal complexes [1, 2] possess potent antitumoral [3–9], antiviral [2, 5, 9–11], antibacterial [3, 5, 10, 12], and antiparasitic [2, 5, 11–14] properties. Anticonvulsant and neurotropic effects are also described in the literature [13, 15].…”

Section: Introductionmentioning

confidence: 99%

Thiosemicarbazonep-Substituted Acetophenone Derivatives Promote the Loss of MitochondrialΔψ, GSH Depletion, and Death in K562 Cells

Pessoto

Yokomizo

Prieto

et al. 2015

Oxidative Medicine and Cellular Longevity

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A series of thiosemicarbazone (TSC) p-substituted acetophenone derivatives were synthesized and chemically characterized. The p-substituents appended to the phenyl group of the TSC structures were hydrogen, fluor, chlorine, methyl, and nitro, producing compounds named TSC-H, TSC-F, TSC-Cl, TSC-Me, and TSC-NO2, respectively. The TSC compounds were evaluated for their capacity to induce mitochondrial permeability, to deplete mitochondrial thiol content, and to promote cell death in the K562 cell lineage using flow cytometry and fluorescence microscopy. TSC-H, TSC-F, and TSC-Cl exhibited a bell-shaped dose-response curve for the induction of apoptosis in K562 cells due to the change from apoptosis to necrosis as the principal mechanism of cell death at the highest tested doses. TSC-Me and TSC-NO2 exhibited a typical dose-response profile, with a half maximal effective concentration of approximately 10 µM for cell death. Cell death was also evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, which revealed lower toxicity of these compounds for peripheral blood mononuclear cells than for K562 cells. The possible mechanisms leading to cell death are discussed based on the observed effects of the new TSC compounds on the cellular thiol content and on mitochondrial bioenergetics.

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Tiossemicarbazonas: métodos de obtenção, aplicações sintéticas e importância biológica

Cited by 47 publications

References 62 publications

Platinum(II) and palladium(II) aryl-thiosemicarbazone complexes: synthesis, characterization, molecular modeling, cytotoxicity, and antimicrobial activity

Platinum(II) and palladium(II) aryl-thiosemicarbazone complexes: synthesis, characterization, molecular modeling, cytotoxicity, and antimicrobial activity

Development of a Novel and Simple Electroanalytical Procedure for the Determination of Copper in Biofuel Employing a Sensor Based on Vulcan Functionalized with Carbazone

Thiosemicarbazonep-Substituted Acetophenone Derivatives Promote the Loss of MitochondrialΔψ, GSH Depletion, and Death in K562 Cells

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