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1.
Ecotoxicol Environ Saf ; 249: 114393, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508808

RESUMO

Semicarbazide (SEM), the metabolite of antibiotic nitrofurazone, is often used as the biomarker to determine the use of nitrofurazone. Frequent false-positive events of SEM have brought great trouble to the aquatic industry in international trade. In this paper, the situation of endogenous SEM in aquatic products was investigated, and the possible mechanism of amino acid conversion into SEM was studied by establishing a simulated oxidation system and a urea system. The results revealed the presence of endogenous SEM in the muscle tissue of shrimps, and the content of SEM ranged from 0.56 to 5.28 ng/g, which presented as Macrobrachium nipponense>Macrobrachium rosenbergii>Procambarus clarkii. The increase in SEM production of control lysine under natural oxidation conditions suggests that oxidation has an effect on the conversion of SEM. Under the action of the simulated oxidation system, the SEM of Arginine, Lysine, Citrulline and Glutamine among the 21 amino acids were increased, and the polymer azine was formed. In combination with the structure of four amino acids, it was presumed that the group of amide is a key intermediate structure for the formation of endogenous SEM. In addition, under the urea system, the content of SEM produced by amino acids increased after the addition of urea, and the concentration of urea had a significant correlation with the content of SEM. Taken together, the production of endogenous SEM in shrimps is related to amino acids and urea, and the urea cycle and other substances containing amide structures should also be considered in future explorations.


Assuntos
Nitrofurazona , Palaemonidae , Animais , Aminoácidos , Lisina , Comércio , Internacionalidade , Semicarbazidas/metabolismo , Ureia/química , Palaemonidae/metabolismo
2.
Molecules ; 27(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36500416

RESUMO

A multicolor immunochromatographic assay platform based on quantum dot nanobeads (QBs) for the rapid and simultaneous detection of nitrofuran metabolites in different aquatic products is documented. These metabolites include 3-amino-2-oxazolidinone (AOZ), 1-aminohydantoin (AHD), semicarbazide (SEM), and 3-amino-5-morpholino-methyl-1,3-oxazolidinone (AMOZ). QBs with emission colors of red, yellow, green, and orange were employed and functionalized with the corresponding antibodies to each analyte to develop a multicolor channel. The visual detection limits (cutoff values) of our method for AOZ, AHD, SEM, and AMOZ reached up to 50 ng/mL, which were 2, 20, 20, and 20 times lower than those of traditional colloidal gold test strips, respectively. The test strip is capable of detection within 10 min in real samples while still achieving good stability and specificity. These results demonstrate that the developed multicolor immunochromatographic assay platform is a promising technique for multiplex, highly sensitive, and on-site detection of nitrofuran metabolites.


Assuntos
Nitrofuranos , Pontos Quânticos , Contaminação de Alimentos/análise , Nitrofuranos/química , Cromatografia de Afinidade/métodos , Semicarbazidas
3.
Eur J Med Chem ; 244: 114812, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36274280

RESUMO

The increasing resistance of Toxoplasma gondii to drugs and side effects of therapy indicate that specific treatment for these parasites is still needed. The 4-arylthiosemicarbazide derivatives seem to be a solution to this challenge because they have low cytotoxicity against host cells and high anti-T. gondii activity. The molecular mechanism for these compounds is related to the inhibition of tyrosine amino acids involved in the proliferation and parasitophorous vacuole formation. The pharmacokinetic analysis shows that 1-(4-Methylimidazol-5-oyl)-4-(4-nitrophenyl)thiosemicarbazide and 4-(3-Iodophenyl)-1-(4-methylimidazol-5-oyl)thiosemicarbazide administered intragastrically pass into the bloodstream and cross the blood-brain barrier, and the absorption of both compounds is first-order absorption. Toxicity analysis shows that our derivatives possess lower toxicity than the routinely used drugs trimethoprim, sulfadiazine and pyrimethamine, as was observed in the level of liver enzymes and creatinine. Both derivatives are highly potent antiparasitic agents against T. gondii, prolonged survival and cure parasite-infected mice. Additionally, significant reductions in cyst formation in the brain and heart were observed, but the highest decreases were noted in muscle and the level of bradyzoites was similar to these observed in mice treated with commercially used drugs. Collectively, the obtained results support the conclusion that both compounds are highly efficacious in a mouse model of acute and chronic toxoplasmosis.


Assuntos
Antiprotozoários , Semicarbazidas , Toxoplasma , Toxoplasmose , Animais , Camundongos , Antiprotozoários/química , Antiprotozoários/farmacocinética , Antiprotozoários/toxicidade , Semicarbazidas/química , Semicarbazidas/farmacocinética , Semicarbazidas/toxicidade , Toxoplasma/efeitos dos fármacos , Toxoplasmose/tratamento farmacológico
4.
Sci Total Environ ; 853: 158676, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36096228

RESUMO

Excessive residues of semicarbazide (SEM) can accumulate in animals after the original drug has been abused, posing a risk to human health. Herein, based on multifunctional silica-initiated dual mode signal response, a novel competitive-type immunosensor was constructed for ultrasensitive detection of SEM. As a preliminary signal amplification platform for immunosensors, polyethyleneimine reduced graphene oxide composite gold nanorods (PEI-rGO/AuNRs) modified gold electrodes (AuE) provide a high specific surface area and high electrical conductivity. The thionine-aminated silica nanospheres-AuPt (thi-SiO2@AuPt) were synthesized by a racile coprecipitation method for enzyme immobilization and redox species loading. The multifunctional silica nanosphere conjugated with labeling antibodies (Ab2) was employed as an immunoprobe. The per unit concentration target of SEM can be determined by differential pulse voltammetry (DPV) to detect the thi loaded on the immunoprobe, which can also be determined by square wave voltammetry (SWV) to detect the current generated by the reaction system of H2O2 and hydroquinone (HQ) catalyzed by the immunoprobe with peroxidase. Under optimal conditions, the proposed immunosensor displayed a wide linear range from 1 µg-0.01 ng/mL and low detection limits (S/N = 3) of 0.488 pg/mL and 0.0157 ng/mL, respectively. Ultimately, the developed method exhibits excellent performance in practical applications, providing promising probabilities for SEM detection.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanocompostos , Nanotubos , Nitrofuranos , Anticorpos Imobilizados/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Grafite/química , Peróxido de Hidrogênio/química , Hidroquinonas , Imunoensaio/métodos , Limite de Detecção , Nanopartículas Metálicas/química , Nanocompostos/química , Nanotubos/química , Peroxidases , Polietilenoimina , Semicarbazidas , Dióxido de Silício/química
5.
Anal Chem ; 94(40): 14004-14011, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36166592

RESUMO

Azodicarbonamide (ADA) is widely used as a flour additive due to its oxidizing and bleaching properties, but it reacts with wet flour during heat processing and is easily decomposed into semicarbazide with genotoxicity and carcinogenicity. In order to improve the efficiency of food safety supervision and expand the scope of food safety control, it is of great significance to develop a facile method for point-of-care testing (POCT) of ADA. Herein, a field-portable and universal smartphone-based photoacoustic (PA) integration device is constructed for quantitative POCT of ADA in flour. The recognition probe Prussian blue with favorable stability is loaded on a flexible substrate for fabricating a portable test strip. In the presence of target ADA, the PA signal changes driven by a modulated 808 nm laser beam can be conveniently collected through the recording application (Audio Lab) of the smartphone. By combining the economic test strip and portable PA device with smartphone readout, it not only greatly simplifies the operation steps but also dramatically reduces the size and cost of the instrument. There is a favorable linear relationship between the PA signal and ADA concentration in the range of 10-200 µmol L-1 (R2 = 0.9928), and a detection limit of 5 µmol L-1 obtained is much lower than the maximum allowable ADA level in the extract of flour (388 µmol L-1). The present miniature PA device with strong POCT ability holds enormous public health significance and economic value in the field of food safety, especially in resource-limited settings.


Assuntos
Compostos Azo , Smartphone , Compostos Azo/química , Testes Imediatos , Semicarbazidas
6.
Sci Rep ; 12(1): 16095, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167735

RESUMO

Here, we report the synthesis, carbonic anhydrase-II (CA-II) inhibition and structure-activity relationship studies of cinnamaldehyde-clubbed thiosemicarbazones derivatives. The derivatives showed potent activities in the range of 10.3 ± 0.62-46.6 ± 0.62 µM. Among all the synthesized derivatives, compound 3n (IC50 = 10.3 ± 0.62 µM), 3g (IC50 = 12.1 ± 1.01 µM), and 3h (IC50 = 13.4 ± 0.52 µM) showed higher inhibitory activity as compared to the standard inhibitor, acetazolamide. Furthermore, molecular docking of all the active compounds was carried out to predict their behavior of molecular binding. The docking results indicate that the most active hit (3n) specifically mediate ionic interaction with the Zn ion in the active site of CA-II. Furthermore, the The199 and Thr200 support the binding of thiosemicarbazide moiety of 3n, while Gln 92 supports the interactions of all the compounds by hydrogen bonding. In addition to Gln92, few other residues including Asn62, Asn67, The199, and Thr200 play important role in the stabilization of these molecules in the active site by specifically providing H-bonds to the thiosemicarbazide moiety of compounds. The docking score of active hits are found in range of - 6.75 to - 4.42 kcal/mol, which indicates that the computational prediction correlates well with the in vitro results.


Assuntos
Inibidores da Anidrase Carbônica , Tiossemicarbazonas , Acetazolamida , Acroleína/análogos & derivados , Anidrase Carbônica II/metabolismo , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Semicarbazidas , Relação Estrutura-Atividade , Tiossemicarbazonas/farmacologia
7.
Sensors (Basel) ; 22(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36015966

RESUMO

Naftazone is a quinone-semi carbazone drug that possesses a strong orange color, and hence it was usually analyzed colorimetrically or by HPLC-UV. However, these methods are not sensitive enough to determine naftazone in biological samples. Naftazone lacks intrinsic fluorescence and does not possess easily derivatizable functional groups. In this contribution, we introduced the first spectrofluorimetric method for naftazone assay through reduction-elicited fluorogenic derivatization through the reduction of its quinone-semicarbazone moiety to the corresponding quinol-semicarbazide derivative by potassium borohydride as a reduction probe. The solvent-dependent fluorescence of the reaction product was studied in various protic and aprotic solvents. Eventually, the fluorescence of the reduced naftazone was measured in 2-propanol at λemission of 350 nm after excitation at λecxitation of 295 nm. The relative fluorescence intensity was linearly correlated to the drug concentration (r = 0.9995) from 10.0 to 500 ng/mL with high sensitivity, where the lower detection limit was 2.9 ng/mL. Hence, the method was effectively applied for naftazone tablets quality control with a mean %recovery of 100.3 ± 1.5, and the results agreed with those of the comparison HPLC-UV method. Furthermore, a new salting-out assisted liquid-liquid extraction (SALLE) method was established for naftazone extraction from human serum, followed by its determination using the developed reduction-based fluorogenic method. The developed SALLE method showed excellent recovery for naftazone from human serum (92.3-106.5%) with good precision (RSD ≤ 6.8%). Additionally, the reaction of naftazone with potassium borohydride was kinetically monitored, and it was found to follow pseudo-first-order kinetics with an activation energy of 43.8 kcal/mol. The developed method's greenness was approved using three green analytical chemistry metrics.


Assuntos
Naftoquinonas , Semicarbazonas , Humanos , Hidroquinonas , Semicarbazidas , Solventes , Espectrometria de Fluorescência , Comprimidos
8.
Sci Rep ; 12(1): 14347, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999336

RESUMO

A novel, efficient, and recoverable nanomagnetic catalyst bearing the semicarbazide linkers, namely, Fe3O4@SiO2@OSi(CH2)3-N(3-pyridoyl sulfonic acid)semicarbazide (FSiPSS) was designed, synthesized and characterized by the use of various techniques such as FT-IR, EDX, elemental mapping analysis, XRD, SEM, TEM, TGA/DTA, BET, and VSM. Then, the catalytic capability of the novel prepared nanomagnetic FSiPSS catalyst was successfully investigated in the synthesis of diverse pyranopyrazoles through a one-pot four-component condensation reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehydes, and malononitrile or ethyl cyano-acetate by the help of ultrasonication in very short reaction time, good to high yields and easy work-up (Fig. 1). Figure 1 Synthesis of diverse pyranopyrazoles by the FSiPSS nano-catalyst.


Assuntos
Dióxido de Silício , Ácidos Sulfônicos , Catálise , Semicarbazidas , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 78(Pt 4): 685-694, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35975834

RESUMO

A new PbII coordination complex [PbL(OAc)], which was readily synthesized from a mixture of Pb(OAc)2·3H2O and 1-(pyridin-2-yl)benzylidene-4-phenylthiosemicarbazide (HL) is reported. The crystal structure analysis of [PbL(OAc)] showed that the PbII cation is N,N',S-chelated by the tridentate pincer-type ligand L and by the oxygen atoms of the acetate anion. In addition, the metal centre forms Pb...O and Pb...S tetrel bonds with an adjacent complex molecule, yielding a 1D zigzag polymeric chain, which is reinforced by N-H...O hydrogen bonds and π...π interactions. These chains are interlinked by C-H...py non-covalent interactions, realized between one of the acetate hydrogen atoms and the pyridine rings. According to the Hirshfeld surface analysis, the crystal packing is mainly characterized by intermolecular H...H, H...C and H...O contacts, followed by H...N, H...S, C...C, C...N, Pb...H, Pb...O and Pb...S contacts. The FTIR and 1H NMR spectra of [PbL(OAc)] testify to the deprotonation of the parent ligand HL, while the acetate ligand exhibits an anisobidentate coordination mode as established by means of single-crystal X-ray diffraction and FTIR spectroscopy. Lastly, theoretical calculations at the PBE0-D3/def2-TZVP level of theory have been used to analyze and characterize the Pb...O and Pb...S tetrel bonds observed in the crystal of [PbL(OAc)], using a combination of QTAIM (Quantum Theory of Atoms in Molecules) and NCIPlot (Non-Covalent Interaction Plot) computational tools.


Assuntos
Acetatos , Chumbo , Ligação de Hidrogênio , Ligantes , Semicarbazidas
10.
Arch Biochem Biophys ; 728: 109371, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35921901

RESUMO

In this study, we investigated whether modification of the carboxyl group with semicarbazide-enabled myoglobin (Mb) exhibits membrane-perturbing activity in physiological solutions. Mass spectrometry analysis showed that semicarbazide molecules were coupled to 19 of the 22 carboxyl groups in semicarbazide-modified Mb (SEM-Mb). Measurements of the absorption and circular dichroism spectra indicated that SEM-Mb lost its heme group and reduced the content of the α-helix structure in Mb. The microenvironment surrounding Trp residues in Mb changes after blocking negatively charged residues, as shown by fluorescence quenching studies. The results of the trifluoroethanol-induced structural transition indicated that SEM-Mb had higher structural flexibility than that of Mb. SEM-Mb, but not Mb, induced the permeability of bilayer membranes. Both proteins showed similar lipid-binding affinities. The conformation of SEM-Mb and Mb changed upon binding to lipid vesicles or a membrane-mimicking environment composed of SDS micelles, suggesting that membrane interaction modes differ. Unlike lipid-bound Mb, Trp residues in lipid-bound SEM-Mb are located at the protein-lipid interface. Altogether, our data indicate that modifying negatively charged groups relieves the structural constraints in Mb, consequently switching Mb structure to an active conformation that exhibits membrane-permeabilizing activity.


Assuntos
Mioglobina , Semicarbazidas , Dicroísmo Circular , Lipídeos , Conformação Proteica , Conformação Proteica em alfa-Hélice
11.
Molecules ; 27(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35889480

RESUMO

A novel series of thiosemicarbazide-substituted coumarins was synthesized and the inhibitory effects against four physiologically relevant carbonic anhydrase isoforms I, II, IX and XII showed selective activities on the tumor-associated IX and XII isozymes. Molecular modeling studies on selected compounds 14a and 22a were performed. The binding modes of such compounds were determined assuming their enzymatically active structures (i.e., cinnamic acid) in the thermodynamically favored, and not previously explored, E geometry. Molecular modelling suggests multiple interactions within the enzymatic cavity and may explain the high potency and selectivity reported for the hCAs IX and XII.


Assuntos
Anidrases Carbônicas , Neoplasias , Antígenos de Neoplasias/metabolismo , Anidrase Carbônica I , Anidrase Carbônica IX/química , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/química , Cumarínicos/química , Cumarínicos/farmacologia , Humanos , Estrutura Molecular , Neoplasias/tratamento farmacológico , Semicarbazidas , Relação Estrutura-Atividade
12.
Molecules ; 27(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35684489

RESUMO

The cyclic anhydrides are broadly employed in several fields, such as the chemical, plastic, agrochemical, and pharmaceutical industries. This study describes the chemical reactivity of 4,5-dichlorophthalic anhydride towards several nucleophiles, including thiosemicarbazide and different amines, to produce the carboxylic acid derivatives resulting from anhydride's opening, namely, phthalimide and dicarboxylic acid (1-12) products. Their chemical structures are confirmed by NMR, IR and MS spectra analyses. Density-functional theory (DFT) studies are performed using (DFT/B3LYP) with the 6-311G(d, p) basis sets to recognize different chemical and physical features of the target compounds.


Assuntos
Aminas , Anidridos , Aminas/química , Anidridos/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Semicarbazidas , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
13.
Org Biomol Chem ; 20(22): 4569-4588, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35593300

RESUMO

A general and stereoselective five-step approach to 14-membered cyclic bis-semicarbazones, 5,12-diaryl-7,14-dimethyl-1,2,4,8,9,11-hexaazacyclotetradeca-7,14-diene-3,10-diones, starting from aldehyde semicarbazones has been developed. The key intermediates, 4-(3-oxobut-1-yl)semicarbazones, were prepared by BF3-catalyzed amidoalkylation of 2-(trimethylsilyloxy)propene with 4-[(aryl)(methoxy)methyl]- or 4-[(aryl)(tosyl)methyl]semicarbazones. Treatment of these intermediates with excess of hydrazine gave hydrazones of 4-(3-oxobut-1-yl)semicarbazones or 4-(3-oxobut-1-yl)semicarbazides, which in the presence of TsOH were converted into the target macrocycles. All steps of this approach could be scaled up easily to the multi-gram level.


Assuntos
Semicarbazonas , Alcenos , Catálise , Semicarbazidas
14.
Molecules ; 27(10)2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35630638

RESUMO

The emergence of drug-resistant bacterial strains continues to be one of the major challenges of medicine. For this reason, the importance of searching for novel structures of antibacterial drugs chemically different from the currently known antibiotics is still of great importance. In this study, we synthesized the thiosemicarbazide and 1,3,4-thiadiazole derivatives and tested them for antibacterial activity. In in vitro tests, we examined the activity of the synthesized substances against Gram-positive and Gram-negative bacteria strains. While all 1,3,4-thiadiazoles tested lacked significant activity, the antimicrobial response of the thiosemicarbazides was moderate and it was also dependent on the type and position of the substituent on the phenyl ring. The highest activity towards all Gram-positive bacteria strains was shown by all three linear compounds containing the trifluoromethylphenyl group in the structure. The MIC (minimum inhibitory concentration) values were in the range of 3.9-250 µg/mL. Additionally, we try to explain the mechanism of the antibacterial activity of the tested compounds using the molecular docking to DNA gyrase and topoisomerase IV, following previous reports on the molecular basis of the activity of thiosemicarbazides. Docking simulations allow the purposing dual mechanism of the antibacterial activity of the synthesized compounds through inhibition of topoisomerase IV DNA gyrase with the moderate prevalence of the topoisomerase pathway.


Assuntos
Antibacterianos , Tiadiazóis , Antibacterianos/química , DNA Girase/metabolismo , DNA Topoisomerase IV , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/metabolismo , Simulação de Acoplamento Molecular , Semicarbazidas , Tiadiazóis/farmacologia
15.
Bioorg Chem ; 124: 105832, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35500502

RESUMO

Thiosemicarbazides (TSCs), dithiocarbamates (DTCs) and their molecular conjugates are promising drug targets. However, hybrids of DTCs with TSCs themselves are rarely investigated. Thus, studies were initiated to synthesize novel system derived from TSC-DTCs to examine their pharmacological applications. The targeted conjugates were designed and synthesized from aryl TSC and aryl DTCs in moderate to good yields. The structures of synthesized compounds were confirmed through FT-IR, 1H NMR, 13C NMR and mass spectrometry. The conjugates have been tested for antioxidant and anticancer activities. The in vitro antioxidant activity was performed using 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical scavenging assay, hydrogen peroxide scavenging assay and nitric oxide assay and was also compared with aryl DTCs and aryl TSCs to explore potential of newly synthesized hybrids. The preliminary anticancer screening for cytotoxicity was performed using brine shrimp lethality bioassay using Artemia salina shrimps. Anticancer screening was determined against NCI60 human tumor cell lines at NCI, USA. The results revealed that, newly synthesized hybrids are more active as compared to aryl DTCs and aryl TSCs. Among the tested conjugates for antioxidant screening, 3b was found to be more active than the standard ascorbic acid. The IC50 value of 3b were 8.96 ± 0.089, 10.7 ± 0.016 and 12.29 ± 0.086 µg/ml for DPPH, hydrogen peroxide scavenging assay and nitric oxide assay respectively, whereas IC50 values for standard were 11.75 ± 0.015, 12.03 ± 0.107 and 16.66 ± 0.242 µg/ml respectively. Since hybrids are more active than aryl DTCs and aryl TSCs, only newly synthesized hybrids were screened for anticancer potential. For cytotoxicity screening, compound 3b was found to be most active among synthesized conjugates with LD50 value of 33.86 µg/ml. For anticancer screening, the compounds 3c and 3d were found to be potent among synthesized series with percent growth inhibition of 22 to 44% when screened against colon cancer cell lines whereas, compound 3b showed growth inhibition of 40% for selective leukemia cell line, K-562. The compounds 3b, 3c and 3d with strong electron-withdrawing groups were found to be the most active antioxidant and anticancer agents among the synthesized conjugates.


Assuntos
Antineoplásicos , Antioxidantes , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Artemia , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Peróxido de Hidrogênio/farmacologia , Óxido Nítrico/farmacologia , Semicarbazidas , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Molecules ; 27(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35566053

RESUMO

A novel biologically active thiosemicarbazide derivative ligand L (N-[(phenylcarbamothioyl)amino]pyridine-3-carboxamide) and a series of its five metal(II) complexes, namely: [Co(L)Cl2], [Ni(L)Cl2(H2O)], [Cu(L)Cl2(H2O)], [Zn(L)Cl2] and [Cd(L)Cl2(H2O)] have been synthesized and thoroughly investigated. The physicochemical characterization of the newly obtained compounds has been performed using appropriate analytical techniques, such as 1H and l3C nuclear magnetic resonance (NMR), inductively coupled plasma (ICP), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR) and magnetic measurements. In order to study the pharmacokinetic profile of the compounds, ADMET analysis was performed. The in vitro studies revealed that the synthesized compounds exhibit potent biological activity against A549 human cancer cell line.


Assuntos
Complexos de Coordenação , Cádmio/química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/química , Humanos , Ligantes , Semicarbazidas/farmacologia , Espectrofotometria Infravermelho , Zinco/química
17.
Food Chem ; 390: 133136, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35545002

RESUMO

The paper presents novel analytical methods for sensitive mercury determination in various samples, i.e., waters, beverages, seafood, plants, and biological samples. The procedure is based on selective preconcentration/separation of Hg(II) ions using graphene oxide/thiosemicarbazide in dispersive micro-solid phase extraction (DMSPE) and detection by energy-dispersive (EDXRF) and total-reflection X-ray fluorescence spectrometry (TXRF). The DMSPE/EDXRF and DMSPE/TXRF procedures are characterized by very high enrichment factors and low detection limits (LODs). DMSPE/TXRF allows obtaining LODs of 2.1 pg mL-1 for liquids and 1.8 ng g-1 for solid samples. In the case of DMSPE/EDXRF, the LODs are higher, 60 pg mL-1 for liquid and 73 ng g-1 for solid samples, due to the worse sensitivity of EDXRF measurement. The method was validated using spiked samples (water, apple juice, beer, wine) and certified reference materials (seawater, groundwater, wastewater, herring, cormorant and cod tissues, pig kidney, lobster, tobacco, scallion, celery, and spinach).


Assuntos
Mercúrio , Água , Animais , Bebidas , Grafite , Semicarbazidas , Suínos , Água/química
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 279: 121396, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35636135

RESUMO

A novel cationic iridium(III) complex [(ppy)2Ir(bPCPC)]PF6 (ppy: 2-phenylpyridine; bPCPC: 2-([2,2'-bipyridine]-4-carbonyl)-N-phenylhydrazinecarbothioamide) containing a thiosemicarbazide unit was designed and synthesized. The thiosemicarbazide unit was a sensitive functional group to Hg2+, when it reacted with Hg2+, it was desulphurized and thus led to the formation of 1,3,4-oxadiazole, [(ppy)2Ir(bPCPC)]PF6 resultantly was used as a "turn-on" chemodosimeter for luminescent detection of Hg2+ in DMF/PBS buffer solution at pH = 7-11. Except for Ag+, recognition capability of [(ppy)2Ir(bPCPC)]PF6 to Hg2+ was not interfered by other common metal ions (Co2+, Li+, Zn2+, Pb2+, K+, Al3+, Na+, Mn2+, Cu2+, Fe2+, Fe3+, Cr3+, Ba2+, Mg2+, Ni2+ and Ca2+). The detection limit was 1.83 × 10-9 mol∙L-1 (0.37 ppb), which indicated the complex was a highly sensitive chemiluminescent detection reagent of Hg2+.


Assuntos
Irídio , Mercúrio , Cátions , Semicarbazidas
19.
Molecules ; 27(5)2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35268797

RESUMO

Nur77 is an orphan nuclear receptor that participates in the occurrence and development of a variety of tumors. Many agonists of Nur77 have been reported to have significant anticancer effects. Our previous studies have found that the introduction of bicyclic aromatic rings, such as naphthalyl and quinoline groups, into the N'-methylene position of indoles' Nur77 modulators can effectively improve the anti-tumor activity of the target compounds. Following our previous studies, a series of novel 1-(2-(6-methoxynaphthalen-2-yl)-6-methylnicotinoyl)-4-substituted semicarbazide/thiosemicarbazide derivatives 9a-9w were designed and synthesized in four steps from 6-methoxy-2-acetonaphthone and N-dimethylformamide dimethylacetal. All compounds were characterized by 1H-NMR, 13C-NMR and HRMS, and their anti-tumor activity on various cancer cell lines such as A549, HepG2, HGC-27, MCF-7 and HeLa are also evaluated. From the series of compounds, 9h exhibited the most potent anti-proliferative activity against several cancer cells. Colony formation and cell cycle experiments showed that compound 9h inhibited cell growth and arrested the cell cycle. Additionally, 9h leads to the cleavage of PARP. We initially explored the mechanism of 9h-induced apoptosis and found that compound 9h can upregulate Nur77 expression and triggered Nur77 nuclear export, indicating the occurrence of Nur77-mediated apoptosis. These results suggested that 9h may be a promising anti-tumor leading compound for the further research.


Assuntos
Semicarbazidas
20.
Int J Mol Sci ; 23(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35328634

RESUMO

Approximately one-third of the human population is infected with the intracellular cosmopolitan protozoan Toxoplasma gondii (Tg), and a specific treatment for this parasite is still needed. Additionally, the increasing resistance of Tg to drugs has become a challenge for numerous research centers. The high selectivity of a compound toward the protozoan, along with low cytotoxicity toward the host cells, form the basis for further research, which aims at determining the molecular targets of the active compounds. Thiosemicarbazide derivatives are biologically active organic compounds. Previous studies on the initial preselection of 58 new 4-arylthiosemicarbazide derivatives in terms of their anti-Tg activity and selectivity made it possible to select two promising derivatives for further research. One of the important amino acids involved in the proliferation of Tg and the formation of parasitophorous vacuoles is tyrosine, which is converted by two unique aromatic amino acid hydroxylases to levodopa. Enzymatic studies with two derivatives (R: para-nitro and meta-iodo) and recombinant aromatic amino acid hydroxylase (AAHs) obtained in the E. coli expression system were performed, and the results indicated that toxoplasmic AAHs are a molecular target for 4-arylthiosemicarbazide derivatives. Moreover, the drug affinity responsive target stability assay also confirmed that the selected compounds bind to AAHs. Additionally, the anti-inflammatory activity of these derivatives was tested using THP1-Blue™ NF-κB reporter cells due to the similarity of the thiosemicarbazide scaffold to thiosemicarbazone, both of which are known NF-κB pathway inhibitors.


Assuntos
Anti-Inflamatórios , Antiprotozoários , Oxigenases de Função Mista , Semicarbazidas , Toxoplasma , Anti-Inflamatórios/farmacologia , Antiprotozoários/farmacologia , Escherichia coli , Humanos , Oxigenases de Função Mista/antagonistas & inibidores , NF-kappa B , Semicarbazidas/farmacologia , Toxoplasma/efeitos dos fármacos , Tirosina
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