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1.
ChemSusChem ; 17(8): e202400234, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38441462

RESUMO

As we work to transition the modern society that is based on non-renewable chemical feedstocks to a post-modern society built around renewable sources of energy, fuels, and chemicals, there is a need to identify the renewable resources and processes for converting them to platform chemicals. Herein, we explore a strategy for utilizing the p-hydroxybenzoate in biomass feedstocks (e. g., poplar and palm trees) and converting it into a portfolio of commodity chemicals. The targeted bio-derived product in the first processing stage is p-hydroxybenzamide produced from p-hydroxybenzoate esters found in the plant. In the second stage a continuous reaction process converts the p-hydroxybenzamide to p-aminophenol via the Hofmann rearrangement and recovers the unreacted p-hydroxybenzamide. In the third stage the p-aminophenol can be acetylated to form paracetamol, which is readily isolated by liquid/liquid extraction at >95 % purity and an overall p-hydroxybenzamide-to-paracetamol process yield of ~90 %. We explore how utilization of protecting groups alters the challenges in this process and expands the portfolio of possible products to include p-(methoxymethoxy)aniline and N-acetyl-p-(methoxymethoxy)aniline. These target compounds could become value-added renewably-sourced platform chemicals that could be used to produce biodegradable plastics, pigments, and pharmaceuticals.


Assuntos
Acetaminofen , Aminofenóis , Biomassa , Aminofenóis/química , Acetaminofen/química , Acetaminofen/síntese química , Benzamidas/química , Benzamidas/síntese química , Técnicas de Química Sintética , Parabenos/química
2.
Org Biomol Chem ; 21(14): 2983-2989, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36942556

RESUMO

Nitric oxide (NO) is a signaling molecule that plays a variety of functions in the human body, but it is difficult to use it in biological experiments or for therapeutic purposes because of its high reactivity and instability in the biological milieu. Consequently, photocontrollable NO releasers, which enable spatiotemporal control of NO release, have an important role in elucidating the functions of NO. Our group has developed visible-light-controllable NO-releasing molecules that contain a fluorescent dye structure as a light-harvesting antenna moiety and an N-nitrosoaminophenol structure as an NO-releasing moiety. Here, we aimed to construct an NO-generating system employing an intermolecular photoredox reaction between the two separate components, since this would simplify chemical synthesis and make it easier to examine various dyes as antennae. For this purpose, we constructed polymer nanoparticles doped with both N-methyl-N-nitroso-4-aminophenol (NAP, 1) and an Ir(III) antenna complex (2, 3 or 4) in order to dissolve in aqueous solution without a co-solvent. These polymer nanoparticles released NO upon photoirradiation in vitro in the purple (400-430 nm) or blue (400-460 nm) wavelength region to activate the doped Ir(III) complex.


Assuntos
Óxido Nítrico , Polímeros , Humanos , Óxido Nítrico/química , Polímeros/química , Aminofenóis/química , Corantes Fluorescentes/química
3.
Molecules ; 27(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209141

RESUMO

In the present study, five 4-aminophenol derivatives (4-chloro-2-(((4-hydroxyphenyl)imino)methyl)phenol(S-1), 4-((4-(dimethylamino)benzylidene)amino)phenol(S-2), 4-((3-nitrobenzylidene)amino)phenol(S-3), 4-((thiophen-2-ylmethylene)amino)phenol(S-4) and 4-(((E)-3-phenylallylidene)amino)phenol(S-5)) were synthesized and characterized by FT-IR, 1H-NMR, 13C-NMR and elemental analyses. The synthesized compounds were tested for their antimicrobial (Gram-positive and Gram-negative bacteria and Saccharomyces cervesea fungus) and antidiabetic (α-amylase and α-glucosidase inhibitory) activities. All the compounds showed broad-spectrum activities against the Staphylococcus aureus (ATCC 6538), Micrococcus luteus (ATCC 4698), Staphylococcus epidermidis (ATCC 12228), Bacillus subtilis sub. sp spizizenii (ATCC 6633), Bordetella bronchiseptica (ATCC 4617) and Saccharomyces cerevisiae (ATCC 9763) strains. The newly synthesized compounds showed a significant inhibition of amylase (93.2%) and glucosidase (73.7%) in a concentration-dependent manner. Interaction studies of Human DNA with the synthesized Schiff bases were also performed. The spectral bands of S-1, S-2, S-3 and S-5 all showed hyperchromism, whereas the spectral band of S-4 showed a hypochromic effect. Moreover, the spectral bands of the S-2, S-3 and S-4 compounds were also found to exhibit a bathochromic shift (red shift). The present studies delineate broad-spectrum antimicrobial and antidiabetic activities of the synthesized compounds. Additionally, DNA interaction studies highlight the potential of synthetic compounds as anticancer agents. The DNA interaction studies, as well as the antidiabetic activities articulated by the molecular docking methods, showed the promising aspects of synthetic compounds.


Assuntos
Aminofenóis/síntese química , Aminofenóis/farmacologia , DNA/química , Aminofenóis/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Sítios de Ligação , Técnicas de Química Sintética , DNA/metabolismo , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Testes de Sensibilidade Microbiana , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Bases de Schiff/química , Análise Espectral , Relação Estrutura-Atividade
4.
Chem Commun (Camb) ; 58(17): 2842-2845, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35129192

RESUMO

We report aminophenol (A)-modified gold nanoparticles (AGNPs), which have potent antibacterial effects against multidrug-resistant bacteria with a broad antibacterial spectrum. Moreover, a series of in vitro and in vivo models indicate that AGNPs are much less ototoxic than aminoglycosides. AGNPs thus have the potential to replace aminoglycosides as novel antibacterial agents for clinical applications.


Assuntos
Aminofenóis/química , Bactérias/efeitos dos fármacos , Ouro/química , Nanopartículas Metálicas/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cães , Escherichia coli/efeitos dos fármacos , Humanos , Larva/efeitos dos fármacos , Larva/fisiologia , Nanopartículas Metálicas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peixe-Zebra/crescimento & desenvolvimento
5.
Mikrochim Acta ; 189(1): 1, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34855022

RESUMO

Mo5N6 nanosheets were synthesized by a nickel-induced growth method and were found to possess peroxidase-like activity in acidic condition and catalase-like activity in weak basic condition. In acidic condition, Mo5N6 nanosheets can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 to form a blue color product (TMBOX). At the co-existence of 4-aminophenol (4-AP), 4-AP can react with H2O2 and TMBOX, resulting in the decrease of TMBOX and the fading of blue color. Therefore, a facile, sensitive colorimetric method for the quantitative detection of 4-AP was developed. The linear range for 4-AP was 1.0 to 80.0 µmol⋅L‒1 (R2 = 0.999), and the detection limit was 0.56 µmol⋅L‒1 based on 3σ/k. Resorcinol, aniline, humic acid, and common ions and anions in surface water did not interfere the determination of 4-AP. This colorimetric method was applied to measure the 4-AP in real water sample from Wulong River in Fujian Province of China. The relative standard deviation for the determination of 4-AP was ranged from 0.03 to 1.88%, and the recoveries from spiked samples were ranged between 99.2 and 107.6%. The determination results were consistent with those obtained by HPLC.


Assuntos
Aminofenóis/análise , Colorimetria/métodos , Nanoestruturas/química , Poluentes da Água/análise , Aminofenóis/química , Benzidinas/química , Catálise , Compostos Cromogênicos/química , Peróxido de Hidrogênio/química , Limite de Detecção , Oxirredução , Rios/química , Poluentes da Água/química
6.
Mikrochim Acta ; 189(1): 2, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34855037

RESUMO

ZnSe nanodisks:Ti3C2 MXene complex was prepared for the first time. Based on its remarkable photoelectrochemical performance, combined with the enzyme-free toehold-mediated strand displacement reaction, a photoelectrochemical biosensor for the detection of the non-small-cell cancer biomarker ctDNA KRAS G12D was developed. ZnSe nanodisks were in situ grown on Ti3C2 MXene surface by two-step hydrothermal method. The high conductivity and adjustable band gap of MXene significantly enhanced the photoelectric response of ZnSe. Subsequently, the photoelectrochemical biosensor was prepared by combining with the signal amplification function of p-aminophenol and the enzyme-free toehold-mediated strand displacement reaction on the modified ITO electrode surface. Under the optimized conditions, the linear detection range is 0.5 ~ 100.0 fM, and the detection limit is 0.2 fM, which realizes the sensitive detection of KRAS G12D. The photoelectrochemical biosensor constructed opens up a new pathway for the preparation of new Mxene-based composite materials and the research of photoelectrochemical biosensor. Nucleic acid liquid biopsy with ZnSe nanodisks:Ti3C2 MXene photoelectroactive modified electrode.


Assuntos
Técnicas Biossensoriais/métodos , DNA Tumoral Circulante/sangue , Nanoestruturas/química , Compostos de Selênio/química , Titânio/química , Compostos de Zinco/química , Aminofenóis/química , Técnicas Biossensoriais/instrumentação , DNA Tumoral Circulante/genética , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Humanos , Limite de Detecção , Mutação , Oxirredução , Proteínas Proto-Oncogênicas p21(ras)/genética , Reprodutibilidade dos Testes
7.
ACS Appl Mater Interfaces ; 13(51): 60878-60893, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34920668

RESUMO

In the quest for designing affordable diagnostic devices with high performance, precisely functionalized carbon-based materials with high accuracy and selectivity are required. Every material has its own unique ability to interact with the analyte, and its performance can be enhanced by probing the interaction mechanism. Herein, p-aminophenol (PAP)-functionalized reduced graphene oxide (rGO) nanoscale material is developed by a one-step synthetic route as an all-organic-based sensor. As the PAP molecules are precisely covalently interacted with the rGO at the basal plane and form a wrinkled-paper-like structure, the functionalized material exhibits an outstanding sensing ability (7.5 nM neurotransmitter dopamine (DA) at a wide linear range, 0.01-100 µM) with fast electrical transduction (<3 s) and good recyclability (∼10 cycles) in a real sample. Combining various analytical and density functional theory (DFT) calculation methods, physicochemical properties and the interaction mechanism of analyte-materials transduction are discussed exclusively. Besides, the potential application of the well-dispersed rGO-PAP gravure ink in flexible-printed electronics fields is explored. This study not only provides new insights into the surface/interface chemistry and working principle of this unique anchoring of PAP on rGO but also offers a new pathway for developing other forms of metal-free/organic functionalized biosensors with high efficiency.


Assuntos
Materiais Biocompatíveis/química , Técnicas Biossensoriais , Dopamina/análise , Técnicas Eletroquímicas , Grafite/química , Neurotransmissores/análise , Aminofenóis/química , Humanos , Teste de Materiais
8.
Int J Biol Macromol ; 193(Pt B): 1645-1652, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34742553

RESUMO

The catalytic reduction reaction is one of the most commonly used solutions to convert high-risk contaminants into safe or low-risk materials. Today, with the increasing water pollution, the urgent need for efficient and effective catalysts is felt more than ever. For this purpose, for the first time, a green catalyst composed of silver nanoparticles anchored on itaconic acid-modified Ca-Al layered double hydroxide/gellan gum nanocomposite (Ag/LDH-ITA-GG NC) was prepared from a green approach without the use of any toxic organic solvents. To gain an in-depth insight into the physicochemical properties of the catalyst, different techniques including nitrogen adsorption-desorption isotherms, FESEM/mapping, FTIR, TGA, and XRD were used. The catalytic performance of the Ag/LDH-ITA-GG NC toward 4-nitrophenol reduction by NaBH4 was investigated. The calculated values of the apparent rate constant for this reaction are 0.2142 min-1 (for 1.0 mg of the catalyst), 0.2375 min-1 (for 3.0 mg of the catalyst), and 0.2550 min-1 (for 5.0 mg of the catalyst), indicating that the catalytic conversion of 4-nitrophenol to 4-aminophenol on the Ag/LDH-ITA-GG NC catalyst follows the pseudo-first-order kinetics and is comparable to the previous findings in the literature. The results of this study indicated that Ag/LDH-ITA-GG NC can potentially be utilized as an auspicious high efficient green catalyst for the reduction of pollutants like 4-nitrophenol.


Assuntos
Hidróxidos/química , Nanopartículas Metálicas/química , Nanocompostos/química , Polissacarídeos Bacterianos/química , Prata/química , Aminofenóis/química , Catálise , Cinética , Nitrofenóis , Succinatos/química
9.
Int J Biol Macromol ; 190: 159-169, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34480903

RESUMO

Bimetallic nanoparticles (BNPs) constitute two different metal elements and exhibit relatively superior mechanistic and catalytic efficacies owing to their synergistic functions over monometallic nanoparticles. In the present study various bimetallic Ag-Au, Ag-Pd, Au-Pd nanoparticles were synthesized using a natural biopolymer gum kondagogu (GK) as a reducing and capping agent, by a simple and cost-effective method. The synthesized BNPs when characterized using UV-vis spectroscopy revealed a specific surface plasmon resonance band (SPR) of each nanocomposite. The average particle size of Ag-Au, Ag-Pd, and Au-Pd BNPs was found to be 23 ± 10.3, 21 ± 7.6, and 23 ± 9.4 nm respectively based on transmission electron microscopy analysis. Surface morphology and functional groups on the gum matrix of GK-BNPs were analyzed by XRD and FT-IR respectively. The bimetallic nanocomposites were evaluated for their catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol in the presence of NaBH4. The kinetic studies performed, depicted rate constants for Ag-Au, Ag-Pd, and Au-PdNPs as 0.31, 0.39, and 0.28 min-1 respectively. The catalytic efficiencies of three bimetallic nanocomposites were of the following order Ag-Pd > Ag-Au > Au-Pd. This study establishes the catalytic potentials of the three different bimetallic nanocomposites in the reduction of 4-NP an environmental pollutant, and the impact of their synergistic property.


Assuntos
Aminofenóis/química , Biopolímeros/química , Bixaceae/química , Metais/química , Nanocompostos/química , Gomas Vegetais/química , Catálise , Difusão , Cinética , Nanocompostos/ultraestrutura , Tamanho da Partícula , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802614

RESUMO

In this study, dense gold-assembled SiO2 nanostructure (SiO2@Au) was successfully developed using the Au seed-mediated growth. First, SiO2 (150 nm) was prepared, modified by amino groups, and incubated by gold nanoparticles (ca. 3 nm Au metal nanoparticles (NPs)) to immobilize Au NPs to SiO2 surface. Then, Au NPs were grown on the prepared SiO2@Au seed by reducing chloroauric acid (HAuCl4) by ascorbic acid (AA) in the presence of polyvinylpyrrolidone (PVP). The presence of bigger (ca. 20 nm) Au NPs on the SiO2 surface was confirmed by transmittance electronic microscopy (TEM) images, color changes to dark blue, and UV-vis spectra broadening in the range of 450 to 750 nm. The SiO2@Au nanostructure showed several advantages compared to the hydrofluoric acid (HF)-treated SiO2@Au, such as easy separation, surface modification stability by 11-mercaptopundecanoic acid (R-COOH), 11-mercapto-1-undecanol (R-OH), and 1-undecanethiol (R-CH3), and a better peroxidase-like catalysis activity for 5,5'-Tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) reaction. The catalytic activity of SiO2@Au was two times better than that of HF-treated SiO2@Au. When SiO2@Au nanostructure was used as a surface enhanced Raman scattering (SERS) substrate, the signal of 4-aminophenol (4-ATP) on the surface of SiO2@Au was also stronger than that of HF-treated SiO2@Au. This study provides a potential method for nanoparticle preparation which can be replaced for Au NPs in further research and development.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Dióxido de Silício/química , Aminofenóis/química , Benzidinas/química , Técnicas Biossensoriais/métodos , Catálise , Ácido Fluorídrico/química , Peróxido de Hidrogênio/química , Limite de Detecção , Povidona/química , Prata/química , Compostos de Sulfidrila/química
11.
Org Biomol Chem ; 19(12): 2784-2793, 2021 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-33704342

RESUMO

Unlike the closely related and widely investigated amidino-substituted benzimidazoles and benzothiazoles with a range of demonstrated biological activities, the matching benzoxazole analogues still remain a largely understudied and not systematically evaluated class of compounds. To address this challenge, we utilized the Pinner reaction to convert isomeric cyano-substituted 2-aminophenols into their amidine derivatives, which were isolated as hydrochlorides and/or zwitterions, and whose structure was confirmed by single crystal X-ray diffraction. The key step during the Pinner synthesis of the crucial carboximidate intermediates was characterized through mechanistic DFT calculations, with the obtained kinetic and thermodynamic parameters indicating full agreement with the experimental observations. The obtained amidines were subjected to a condensation reaction with aryl carboxylic acids that allowed the synthesis of a new library of 5- and 6-amidino substituted 2-arylbenzoxazoles. Their antiproliferative features against four human tumour cell lines (SW620, HepG2, CFPAC-1, HeLa) revealed sub-micromolar activities on SW620 for several cyclic amidino 2-naphthyl benzoxazoles, thus demonstrating the usefulness of the proposed synthetic strategy and promoting amidino substituted 2-aminophenols as important building blocks towards biologically active systems.


Assuntos
Amidinas/farmacologia , Aminofenóis/farmacologia , Antineoplásicos/farmacologia , Benzoxazóis/farmacologia , Amidinas/química , Aminofenóis/química , Antineoplásicos/síntese química , Antineoplásicos/química , Benzoxazóis/síntese química , Benzoxazóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Teoria da Densidade Funcional , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular
12.
J Nat Prod ; 84(3): 814-823, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33523676

RESUMO

Natural product congeners serve a useful role in the understanding of natural product biosynthesis and structure-activity relationships. A minor congener with superior activity, selectivity, and modifiable functional groups could serve as a more effective lead structure and replace even the original lead molecule that was used for medicinal chemistry modifications. Currently, no effective method exists to discover targeted congeners rapidly, specifically, and selectively from producing sources. Herein, a new method based on liquid-chromatography tandem-mass spectrometry combination is evaluated for targeted discovery of congeners of platensimycin and platencin from the extracts of Streptomyces platensis. By utilizing a precursor-ion searching protocol, tandem mass spectrometry not only confirmed the presence of known congeners but also provided unambiguous detection of many previously unknown congeners of platensimycin and platencin. This high-throughput and quantitative method can be rapidly and broadly applied for dereplication and congener discovery from a variety of producing sources, even when the targeted compounds are obscured by the presence of unrelated natural products.


Assuntos
Adamantano/química , Aminobenzoatos/química , Aminofenóis/química , Anilidas/química , Ensaios de Triagem em Larga Escala/métodos , Compostos Policíclicos/química , Streptomyces/química , Adamantano/isolamento & purificação , Aminobenzoatos/isolamento & purificação , Aminofenóis/isolamento & purificação , Anilidas/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Cromatografia Líquida , Estrutura Molecular , Compostos Policíclicos/isolamento & purificação , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem
13.
Bioorg Med Chem ; 35: 116059, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33611014

RESUMO

α,ß-Unsaturated carbonyls are reactive group often found in bioactive small molecules. Their non-specific reaction with biomolecules can be the cause of the low efficacy and unexpected side-effects of the molecule. Accordingly, unprotected α,ß-unsaturated carbonyls are not often found in drugs. Here, we report that o-aminophenol is a new masking group of α,ß-unsaturated ketone, which is inspired by natural products saccharothriolides. o-Aminophenol adduct of α,ß-unsaturated ketone, but not those of α,ß-unsaturated amide or ester, undergoes a retro-Michael reaction to yield o-aminophenol and the Michael acceptor. This reaction was observed only in protic solvents, such as MeOH and aqueous MeOH. In contrast, o-anisidine was not eliminated from its Michael adduct. o-Aminophenol may be a promising masking tool of highly-reactive bioactive α,ß-unsaturated carbonyl compounds.


Assuntos
Aminofenóis/química , Compostos Aza/química , Produtos Biológicos/química , Cetonas/química , Macrolídeos/química , Estrutura Molecular , Solventes/química
14.
Eur J Med Chem ; 213: 113195, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33524685

RESUMO

Cystic fibrosis (CF) is the most frequent life-limiting autosomal recessive disorder in the Caucasian population. It is due to mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. Current symptomatic CF therapies, which treat the downstream consequences of CFTR mutations, have increased survival. Better knowledge of the CFTR protein has enabled pharmacologic therapy aiming to restore mutated CFTR expression and function. These CFTR "modulators" have revolutionised the CF therapeutic landscape, with the potential to transform prognosis for a considerable number of patients. This review provides a brief summary of their mechanism of action and presents a thorough review of the results obtained from clinical trials of CFTR modulators.


Assuntos
Aminofenóis/farmacologia , Aminopiridinas/farmacologia , Benzodioxóis/farmacologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/tratamento farmacológico , Desenvolvimento de Medicamentos , Indóis/farmacologia , Quinolonas/farmacologia , Aminofenóis/síntese química , Aminofenóis/química , Aminopiridinas/síntese química , Benzodioxóis/síntese química , Ensaios Clínicos como Assunto , Fibrose Cística/diagnóstico , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Humanos , Indóis/síntese química , Quinolonas/síntese química , Quinolonas/química
15.
Molecules ; 26(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466934

RESUMO

Using the GUSAR 2013 program, the quantitative structure-antioxidant activity relationship has been studied for 74 phenols, aminophenols, aromatic amines and uracils having lgk7 = 0.01-6.65 (where k7 is the rate constant for the reaction of antioxidants with peroxyl radicals generated upon oxidation). Based on the atomic descriptors (Quantitative Neighborhood of Atoms (QNA) and Multilevel Neighborhoods of Atoms (MNA)) and molecular (topological length, topological volume and lipophilicity) descriptors, we have developed 9 statistically significant QSAR consensus models that demonstrate high accuracy in predicting the lgk7 values for the compounds of training sets and appropriately predict lgk7 for the test samples. Moderate predictive power of these models is demonstrated using metrics of two categories: (1) based on the determination coefficients R2 (R2TSi, R20, Q2(F1), Q2(F2), RmTSi2¯) and based on the concordance correlation coefficient (CCC)); or (2) based on the prediction lgk7 errors (root mean square error (RMSEP), mean absolute error (MAE) and standard deviation (S.D.)) The RBF-SCR method has been used for selecting the descriptors. Our theoretical prognosis of the lgk7 for 8-PPDA, a known antioxidant, based on the consensus models well agrees with the experimental value measure in the present work. Thus, the algorithms for calculating the descriptors implemented in the GUSAR 2013 program allow simulating kinetic parameters of the reactions underling the liquid-phase oxidation of hydrocarbons.


Assuntos
Algoritmos , Aminas/farmacologia , Aminofenóis/farmacologia , Antioxidantes/farmacologia , Fenóis/farmacologia , Uracila/farmacologia , Aminas/química , Aminofenóis/química , Antioxidantes/química , Modelos Moleculares , Oxirredução , Fenóis/química , Relação Quantitativa Estrutura-Atividade , Uracila/química
16.
J Forensic Sci ; 66(1): 285-294, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32956496

RESUMO

The analysis of cannabis plant material submitted to seized-drug laboratories was significantly affected by the signing of the Agricultural Improvement Act of 2018, which defined hemp and removed it from the definition of marijuana in the Controlled Substances Act. As a result, field law enforcement personnel and forensic laboratories now are in need of implementing new protocols that can distinguish between marijuana-type and hemp-type cannabis. Colorimetric tests provide a cost-effective and efficient manner to presumptively identify materials prior to submission to a laboratory for analysis. This work presents the validation of the 4-aminophenol (4-AP) color test and demonstrates its utility for discriminating between marijuana-type and hemp-type cannabis (i.e., typification). Validation studies included the testing of numerous cannabinoid reference materials, household herbs, previously characterized cannabis plant samples, and real-case samples. The 4-AP test reliably produces a pink result when the level of Δ9 -tetrahydrocannabinol (THC) is approximately three times lower than the level of cannabidiol (CBD). A blue result is generated when the level of THC is approximately three times higher than that of CBD. Inconclusive results are observed when the levels of THC and CBD are within a factor of three from each other, demonstrating the limitations of the test under those scenarios.


Assuntos
Aminofenóis/química , Cannabis/química , Colorimetria , Canabinoides/análise , Dronabinol/análise , Humanos
17.
Eur J Med Chem ; 213: 113042, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33257173

RESUMO

Paracetamol, one of the most widely used pain-relieving drugs, is deacetylated to 4-aminophenol (4-AP) that undergoes fatty acid amide hydrolase (FAAH)-dependent biotransformation into N-arachidonoylphenolamine (AM404), which mediates TRPV1-dependent antinociception in the brain of rodents. However, paracetamol is also converted to the liver-toxic metabolite N-acetyl-p-benzoquinone imine already at therapeutic doses, urging for safer paracetamol analogues. Primary amine analogues with chemical structures similar to paracetamol were evaluated for their propensity to undergo FAAH-dependent N-arachidonoyl conjugation into TRPV1 activators both in vitro and in vivo in rodents. The antinociceptive and antipyretic activity of paracetamol and primary amine analogues was examined with regard to FAAH and TRPV1 as well as if these analogues produced acute liver toxicity. 5-Amino-2-methoxyphenol (2) and 5-aminoindazole (3) displayed efficient target protein interactions with a dose-dependent antinociceptive effect in the mice formalin test, which in the second phase was dependent on FAAH and TRPV1. No hepatotoxicity of the FAAH substrates transformed into TRPV1 activators was observed. While paracetamol attenuates pyrexia via inhibition of brain cyclooxygenase, its antinociceptive FAAH substrate 4-AP was not antipyretic, suggesting separate mechanisms for the antipyretic and antinociceptive effect of paracetamol. Furthermore, compound 3 reduced fever without a brain cyclooxygenase inhibitory action. The data support our view that analgesics and antipyretics without liver toxicity can be derived from paracetamol. Thus, research into the molecular actions of paracetamol could pave the way for the discovery of analgesics and antipyretics with a better benefit-to-risk ratio.


Assuntos
Acetaminofen/química , Amidoidrolases/metabolismo , Analgésicos/química , Antipiréticos/química , Canais de Cátion TRPV/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Acetaminofen/farmacologia , Aminofenóis/química , Analgésicos/farmacologia , Animais , Antipiréticos/farmacologia , Ácidos Araquidônicos/química , Encéfalo , Feminino , Humanos , Indazóis/química , Fígado , Masculino , Camundongos Endogâmicos C57BL , Modelos Moleculares , Dor/tratamento farmacológico , Medição da Dor , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos Wistar , Relação Estrutura-Atividade
18.
Chem Asian J ; 16(3): 237-246, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33146945

RESUMO

Silver nanoparticles (AgNPs) are widely sought after for a variety of biomedical and environmental applications due to their antimicrobial and catalytic properties. We present here a green and simple synthesis of AgNPs utilizing traditional Chinese medicinal herbs. The screening of 20 aqueous herb extracts shows that Sheng Di Huang (Rehmannia glutinosa) had the most promising potential in producing AgNPs of 30±6 nm, with narrow size distribution and high crystallinity. The antimicrobial activities of these AgNPs conducted on E. coli cells were found to be superior in comparison to poly(vinylpyrrolidone)-capped AgNPs synthesized using common chemical method. Additionally, the AgNPs obtained possess excellent catalytic performance in the reduction of 4-nitrophenol to 4-aminophenol. We compared the phytochemical and FTIR spectral analyses of the herb extract before and after synthesis, in order to elucidate the phytochemicals responsible for the reduction of Ag+ ions and the capping of the AgNPs produced.


Assuntos
Anti-Infecciosos/síntese química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Rehmannia/química , Prata/química , Aminofenóis/química , Anti-Infecciosos/química , Catálise , Química Verde , Nitrofenóis/química , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Rehmannia/metabolismo
19.
Molecules ; 25(21)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142775

RESUMO

In this work, the cytotoxic behavior of six ruthenium(II) complexes of stoichiometry [(η6-p-cymene)RuCl2L] (I-VI), L = 4-cyanopyridine (I), 2-aminophenol (II), 4-aminophenol (III), pyridazine (IV), and [(η6-p-cymene)RuClL2]PF6; L = cyanopyridine (V), L = 2-aminophenol(VI) towards three cell lines was studied. Two of them, HeLa and MCF-7, are human carcinogenic cells from cervical carcinoma and human breast cancer, respectively. A comparison with healthy cells was carried out with BGM cells which are monkey epithelial cells of renal origin. The behavior of complex II exhibits selectivity towards healthy cells, which is a promising feature for use in cancer treatment since it might reduce the side effects of most current therapies.


Assuntos
Antineoplásicos/síntese química , Complexos de Coordenação/síntese química , Cimenos/química , Rutênio/química , Aminofenóis/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Células MCF-7 , Nitrilas/química , Piridazinas/química , Piridinas/química
20.
Int J Mol Sci ; 21(12)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599772

RESUMO

Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein is expressed at the apical plasma membrane (PM) of different epithelial cells. The most common mutation responsible for the onset of cystic fibrosis (CF), F508del, inhibits the biosynthesis and transport of the protein at PM, and also presents gating and stability defects of the membrane anion channel upon its rescue by the use of correctors and potentiators. This prompted a multiple drug strategy for F508delCFTR aimed simultaneously at its rescue, functional potentiation and PM stabilization. Since ganglioside GM1 is involved in the functional stabilization of transmembrane proteins, we investigated its role as an adjuvant to increase the effectiveness of CFTR modulators. According to our results, we found that GM1 resides in the same PM microenvironment as CFTR. In CF cells, the expression of the mutated channel is accompanied by a decrease in the PM GM1 content. Interestingly, by the exogenous administration of GM1, it becomes a component of the PM, reducing the destabilizing effect of the potentiator VX-770 on rescued CFTR protein expression/function and improving its stabilization. This evidence could represent a starting point for developing innovative therapeutic strategies based on the co-administration of GM1, correctors and potentiators, with the aim of improving F508del CFTR function.


Assuntos
Adjuvantes Imunológicos/farmacologia , Aminofenóis/farmacologia , Aminopiridinas/farmacologia , Benzodioxóis/farmacologia , Fibrose Cística/tratamento farmacológico , Gangliosídeo G(M1)/farmacologia , Quinolonas/farmacologia , Adjuvantes Imunológicos/química , Aminofenóis/química , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/patologia , Agonistas dos Canais de Cloreto/química , Agonistas dos Canais de Cloreto/farmacologia , Fibrose Cística/genética , Fibrose Cística/patologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Gangliosídeo G(M1)/química , Humanos , Mutação , Quinolonas/química , Terapias em Estudo
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