Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
1.
Molecules ; 28(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37894604

RESUMO

In continuation of our research programs for the discovery, production, and development of the pharmacological activities of molecules for various disease treatments, Schiff bases and pyrazole scaffold have a broad spectrum of activities in biological applications. In this context, this manuscript aims to evaluate and study Schiff base-pyrazole molecules as a new class of antioxidant (total antioxidant capacity, iron-reducing power, scavenging activity against DPPH, and ABTS radicals), anti-diabetic (α-amylase% inhibition), anti-Alzheimer's (acetylcholinesterase% inhibition), and anti-arthritic (protein denaturation% and proteinase enzyme% inhibitions) therapeutics. Therefore, the Schiff bases bearing pyrazole scaffold (22a, b and 23a, b) were designed and synthesized for evaluation of their antioxidant, anti-diabetic, anti-Alzheimer's, and anti-arthritic properties. The results for compound 22b demonstrated significant antioxidant, anti-diabetic (α-amylase% inhibition), and anti-Alzheimer's (ACE%) activities, while compound 23a demonstrated significant anti-arthritic activity. Prediction of in silico bioinformatics analysis (physicochemical properties, bioavailability radar, drug-likeness, and medicinal chemistry) of the target derivatives (22a, b and 23a, b) was performed. The molecular lipophilicity potential (MLP) of the derivatives 22a, b and 23a, b was measured to determine which parts of the surface are hydrophobic and which are hydrophilic. In addition, the molecular polar surface area (PSA) was measured to determine the polar surface area and the non-polar surface area of the derivatives 22a, b and 23a, b. This study could be useful to help pharmaceutical researchers discover a new series of potent agents that may act as an antioxidant, anti-diabetic, anti-Alzheimer, and anti-arthritic.


Assuntos
Antioxidantes , Bases de Schiff , Antioxidantes/farmacologia , Antioxidantes/química , Bases de Schiff/química , Acetilcolinesterase/metabolismo , Pirazóis , alfa-Amilases , Estrutura Molecular , Simulação de Acoplamento Molecular
2.
Molecules ; 28(15)2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37570881

RESUMO

Isoflavenes have received the greatest research attention among the many groups of phytoestrogens. In this study, various isoflavene-based Mannich bases were selected for their theoretical studies. The purpose of this research was to discover the binding potential of all the designated Mannich bases acting as inhibitors against cancerous proteins EGFR, cMet, hTrkA, and HER2 (PDB codes: 5GTY, 3RHK, 6PL2, and 7JXH, respectively). For their virtual screening, DFT calculations and molecular docking studies were undertaken using in silico software. Docking studies predicted that ligands 5 and 15 exhibited the highest docking score by forming hydrogen bonds within the active pocket of protein 6PL2, ligands 1 and 15 both with protein 3RHK, and 7JXH, 12, and 17 with protein 5GTY. Rendering to the trends in polarizability and dipole moment, the energy gap values (0.2175 eV, 0.2106 eV) for the firm conformers of Mannich bases (1 and 4) replicate the increase in bioactivity and chemical reactivity. The energy gap values (0.2214 eV and 0.2172 eV) of benzoxazine-substituted isoflavene-based Mannich bases (9 and 10) reflect the increase in chemical potential due to the most stable conformational arrangements. The energy gap values (0.2188 eV and 0.2181 eV) of isoflavenes with tertiary amine-based Mannich bases (14 and 17) reflect the increase in chemical reactivity and bioactivity due to the most stable conformational arrangements. ADME was also employed to explore the pharmacokinetic properties of targeted moieties. This study revealed that these ligands have a strong potential to be used as drugs for cancer treatment.


Assuntos
Bases de Mannich , Fitoestrógenos , Simulação de Acoplamento Molecular , Fitoestrógenos/farmacologia , Bases de Mannich/farmacologia , Bases de Mannich/química , Ligantes
3.
Molecules ; 28(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37049960

RESUMO

5-bromopyridine-2,3-diamine reacted with benzaldehyde to afford the corresponding 6-Bromo-2-phenyl-3H-imidazo[4,5-b]pyridine (1). The reaction of the latter compound (1) with a series of halogenated derivatives under conditions of phase transfer catalysis solid-liquid (CTP) allows the isolation of the expected regioisomers compounds (2-8). The alkylation reaction of (1) gives, each time, two regioisomers, N3 and N4; in the case of ethyl bromoactate, the reaction gives, at the same time, the three N1, N3 and N4 regioisomers. The structures of synthesized compounds were elucidated on the basis of different spectral data (1H NMR, 13C NMR), X-Ray diffraction and theoretical study using the DFT method, and confirmed for each compound. Hirshfeld surface analysis was used to determine the intermolecular interactions responsible for the stabilization of the molecule. Density functional theory was used to optimize the compounds, and the HOMO-LUMO energy gap was calculated, which was used to examine the inter/intra molecular charge transfer. The molecular electrostatic potential map was calculated to investigate the reactive sites that were present in the molecule. In order to determine the potential mode of interactions with DHFR active sites, the three N1, N3 and N4 regioisomers were further subjected to molecular docking study. The results confirmed that these analogs adopted numerous important interactions, with the amino acid of the enzyme being targeted. Thus, the most docking efficient molecules, 2 and 4, were tested in vitro for their antibacterial activity against Gram-positive bacteria (Bacillus cereus) and Gram-negative bacteria (Escherichia coli). Gram-positive bacteria were more sensitive to the action of these compounds compared to the Gram-negative, which were much more resistant.


Assuntos
Anti-Infecciosos , Simulação de Acoplamento Molecular , Conformação Molecular , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias Gram-Positivas , Piridinas/farmacologia , Piridinas/química
4.
J Enzyme Inhib Med Chem ; 35(1): 921-934, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32238055

RESUMO

A new series of N'-(substituted phenyl)-2-(1-(4-(methylsulfinyl) benzylidene)-5-fluoro-2-methyl-1H-inden-3-yl) acetohydrazide derivatives (1 - 25) were prepared in good yields in an efficient manner. All the compounds were fully characterised by the elemental analysis and spectral data. Synthesised compounds were evaluated for antioxidant activity by DPPH method. Compounds 7 (R = 3-methoxyphenyl), 3 (R = 4-dimethylaminophenyl) and 23 (R = 2,4,5-trimethoxy phenyl) substitutions were found to be having highly potent antioxidant activity. Compound 3, with para dimethylaminophenyl substitution was found to be having highest antioxidant activity. It was further evaluated in vivo for various analgesic, anti-inflammatory, ulcerogenic and COX-2 inhibitory activity in different animal models. Lead compound 3 was found to be significant anti-inflammatory and analgesic agent. It was also evaluated for ulcerogenic activity and demonstrated significant ulcerogenic reduction activity in ethanol and indomethacin model. The LD50 of compound 3 was found to be 131 mg/kg. The animals treated with compound 3 prior to cisplatin treatment resulted in a significant reduction in COX-2 protein expression when compared to cisplatin-treated group. Sulindac derivative with para dimethylaminophenyl substitution was found to be the most potent antioxidant, anti-inflammatory and analgesic agent as well as with significant gastric sparing activity as compared to standard drug sulindac. Compound 3 significantly downregulated liver tissue COX-2 gene expression.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Sulindaco/farmacologia , Ácido Acético , Analgésicos/síntese química , Analgésicos/química , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antiulcerosos/síntese química , Antiulcerosos/química , Antioxidantes/síntese química , Antioxidantes/química , Comportamento Animal/efeitos dos fármacos , Compostos de Bifenilo/antagonistas & inibidores , Carragenina , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/síntese química , Inibidores de Ciclo-Oxigenase 2/química , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Etanol , Masculino , Estrutura Molecular , Dor/induzido quimicamente , Dor/tratamento farmacológico , Picratos/antagonistas & inibidores , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Sulindaco/síntese química , Sulindaco/química , Úlcera/induzido quimicamente , Úlcera/tratamento farmacológico
5.
J Enzyme Inhib Med Chem ; 35(1): 1491-1502, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32668994

RESUMO

A novel series of pyrazole analogues including hydrazones, pyrazolo[4,3-c]-pyridazines, pyrazolo[3,4-e][1,2,4]triazine and pyrazolo[3,4-d][1,2,3]triazoles was designed, synthesised and screened for their in vitro antimicrobial and DHFR inhibition activity. Compounds bearing benzenesulphonamide moiety incorporated with 3-methyl-5-oxo-1H-pyrazol-4(5H)-ylidene) hydrazine 3a or 6-amino-7-cyano-3-methyl-5H-pyrazolo[4,3-c]pyridazine 6a revealed excellent and broad spectrum antimicrobial activity comparable to ciprofloxacin and amphotericin B as positive antibiotic and antifungal controls, respectively. Furthermore, these derivatives proved to be the most active DHFR inhibitors with IC50 values 0.11 ± 1.05 and 0.09 ± 0.91 µM, in comparison with methotrexate (IC50 = 0.14 ± 1.25 µM). The in silico studies were done to calculate the drug-likeness and toxicity risk parameters of the newly synthesised derivatives. Additionally, the high potency of the pyrazole derivatives bearing sulphonamide against DHFR was confirmed with molecular docking and might be used as an optimum lead for further modification.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antagonistas do Ácido Fólico/farmacologia , Compostos Heterocíclicos/farmacologia , Pirazóis/farmacologia , Tetra-Hidrofolato Desidrogenase/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Aspergillus/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Antagonistas do Ácido Fólico/síntese química , Antagonistas do Ácido Fólico/química , Compostos Heterocíclicos/química , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Pirazóis/química , Streptococcus pneumoniae/efeitos dos fármacos , Relação Estrutura-Atividade
6.
Molecules ; 25(16)2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32781534

RESUMO

A search for potent antitubercular agents prompted us to design and synthesize sulfamethaoxazole incorporated 4-thiazolidinone hybrids (7a-l) by using a cyclocondensation reaction between 4-amino-N-(5-methylisoxazol-3-yl)benzenesulfonamide (4), aryl aldehyde (5a-l), and mercapto acetic acid (6) resulting in good to excellent yields. All the newly synthesized 4-thiazolidinone derivatives were screened for their in vitro antitubercular activity against M. Bovis BCG and M. tuberculosis H37Ra (MTB) strains. The compounds 7d, 7g, 7i, 7k, and 7l revealed promising antimycobacterial activity against M. Bovis and MTB strains with IC90 values in the range of 0.058-0.22 and 0.43-5.31 µg/mL, respectively. The most active compounds were also evaluated for their cytotoxicity against MCF-7, HCT 116, and A549 cell lines and were found to be non-cytotoxic. Moreover, the synthesized compounds were also analyzed for ADME (absorption, distribution, metabolism, and excretion) properties and showed potential as good oral drug candidates.


Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Oxazóis/síntese química , Oxazóis/farmacologia , Tiazolidinas/química , Antituberculosos/química , Antituberculosos/toxicidade , Linhagem Celular Tumoral , Técnicas de Química Sintética , Humanos , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Oxazóis/química , Oxazóis/toxicidade , Relação Estrutura-Atividade
7.
Molecules ; 25(6)2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32245177

RESUMO

Pyrazolo[1,5-a]pyrimidines 5a-c, 9a-c and 13a-i were synthesized for evaluation of their in vitro antimicrobial properties against some microorganisms and their immunomodulatory activity. The biological activities of pyrazolo[1,5-a]pyrimidines showed that the pyrazolo[1,5-a]pyrimidines (5c, 9a, 9c, 13a, 13c, 13d, 13e and 13h) displayed promising antimicrobial and immunomodulatory activities. Studying the in silico predicted physicochemical, pharmacokinetic, ADMET and drug-likeness properties for the pyrazolo[1,5-a]pyrimidines 5a-c, 9a-c and 13a-i confirmed that most of the compounds (i) were within the range set by Lipinski's rule of five, (ii) show higher gastrointestinal absorption and inhibition of some CYP isoforms, and (iii) have a carcinogenicity test that was predicted as negative and hERG test that presented medium risk. Moreover, the molecular docking study demonstrated that the compounds 5c, 9a, 9c, 13a, 13c, 13d, 13e and 13h are potent inhibitors of 14-alpha demethylase, transpeptidase and alkaline phosphatase enzymes. This study could be valuable in the discovery of a new series of drugs.


Assuntos
Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Pirazóis/farmacologia , Pirimidinas/farmacologia , Inibidores de 14-alfa Desmetilase/farmacologia , Fosfatase Alcalina/antagonistas & inibidores , Aspergillus/efeitos dos fármacos , Células CACO-2 , Candida albicans/efeitos dos fármacos , Testes de Carcinogenicidade/efeitos adversos , Simulação por Computador , Desenho de Fármacos , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Peptidil Transferases/antagonistas & inibidores , Pseudomonas aeruginosa/efeitos dos fármacos , Pirazóis/química , Pirazóis/farmacocinética , Pirazóis/toxicidade , Pirimidinas/química , Pirimidinas/farmacocinética , Pirimidinas/toxicidade , Salmonella typhi/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
8.
Molecules ; 25(16)2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32784576

RESUMO

Within a series of dipeptide derivatives (5-11), compound 4 was refluxed with d-glucose, d-xylose, acetylacetone, diethylmalonate, carbon disulfide, ethyl cyanoacetate, and ethyl acetoacetate which yielded 5-11, respectively. The candidates 5-11 were characterized and their biological activities were evaluated where they showed different anti-microbial inhibitory activities based on the type of pathogenic microorganisms. Moreover, to understand modes of binding, molecular docking was used of Nicotinoylglycine derivatives with the active site of the penicillin-binding protein 3 (PBP3) and sterol 14-alpha demethylase's (CYP51), and the results, which were achieved via covalent and non-covalent docking, were harmonized with the biological activity results. Therefore, it was extrapolated that compounds 4, 7, 8, 9, and 10 had good potential to inhibit sterol 14-alpha demethylase and penicillin-binding protein 3; consequently, these compounds are possibly suitable for the development of a novel antibacterial and antifungal therapeutic drug. In addition, in silico properties of absorption, distribution, metabolism, and excretion (ADME) indicated drug likeness with low to very low oral absorption in most compounds, and undefined blood-brain barrier permeability in all compounds. Furthermore, toxicity (TOPKAT) prediction showed probability values for all carcinogenicity models were medium to pretty low for all compounds.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Desenho de Fármacos , Glicilglicina/síntese química , Glicilglicina/farmacologia , Simulação de Acoplamento Molecular , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Domínio Catalítico , Técnicas de Química Sintética , Família 51 do Citocromo P450/química , Família 51 do Citocromo P450/metabolismo , Glicilglicina/química , Glicilglicina/metabolismo , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Termodinâmica
9.
Molecules ; 25(3)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32023970

RESUMO

Screen-printed membrane sensors based on the use of paper and ceramic substrates are fabricated, characterized, and used for rapid batch and continuous monitoring of CrIII in the form of CrO42- in some industrial products and wastewater samples. Strips of paper and ceramic platforms (15 × 5 mm) were covered with conductive carbon paint and then modified with polyaniline (PANI) film, to act as an ion-to-electron transducer, followed by a drop casting of plasticized poly (vinyl chloride) (PVC) Rhodamine-B chromate membrane as a recognition sensing material. In a 5.0 mmol L-1 Trizma buffer solution of pH ~8, the fabricated paper and ceramic based membrane sensors exhibited a near Nernstian response for CrVI ion with slopes of -29.7 ± 0.5 and -28.6 ± 0.3 mV decade-1, limit of detection 2.5 × 10-5 and 2.4 × 10-6 mol L-1 (1.3-0.12 µg mL-1), and linear concentration range 7.5 × 10-3-5.0 × 10-5 and 7.5 × 10-3-1.0 × 10-5 mol L-1 (390-0.5 µg mL-1), respectively. Both sensors exhibited fast and stable potentiometric response, excellent reproducibility, and good selectivity with respect to a number of common foreign inorganic species. Impedance spectroscopy and chronopotentiometry data revealed a small resistance and a larger double layer capacitance due to the presence of the intermediate polyaniline (PAN) conductive layer. Furthermore, the formation of a water layer between the ion selective membrane (ISM) and the underlying conductor polymer and between the conducting polymer and the carbon conducting surface was greatly reduced. The developed disposable solid-contact potentiometric sensors offer the advantages of simple design, long term potential stability, flexibility, miniaturization ability, short conditioning time, and cost effectiveness that enable mass production. The sensors were successfully used for static and hydrodynamic measurements of total chromium in some leather tanning wastewater and nickel-chrome alloy samples. The results compare favorably with data obtained by atomic absorption spectrometry.


Assuntos
Compostos de Anilina/química , Técnicas Biossensoriais/métodos , Cerâmica/química , Cromo/análise , Acidentes de Trabalho , Hidrodinâmica , Concentração de Íons de Hidrogênio , Nanopartículas , Papel , Plastificantes/química , Polímeros/química , Potenciometria , Espectrofotometria Atômica
10.
Molecules ; 25(12)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545457

RESUMO

Copper ferrite nano-particles (CuFe2O4) were synthesized, characterized, modified with polyaniline to form CuFe2O4/PANI nano-composite. They were used as new adsorbents for the removal of the hazardous mercuric ions from aqueous solutions. High resolution transmission electron microscope (HR-TEM), X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) and Brunauer-Emmett-Teller (BET) were used for the characterization of the synthesized CuFe2O4 nano-particles (NPs) in presence and absence of PANI nano-composite. The synthesized CuFe2O4NPs were of spherical shape with an average size of 10.8 nm. XRD analysis displayed crystal peaks for CuFe2O4NPs and amorphous peaks CuFe2O4/PANI nano-composite due to the existence of polyaniline layer. Contact time, adsorbent dose, solution pH, adsorption kinetics, adsorption isotherm and recyclability were studied. The method at the optimum conditions exhibited high performance with high mercury removal percentage of up to 99% with a maximum adsorption capacity 12.5 and 157.1 mg/g for CuFe2O4 and CuFe2O4/PANI, respectively. The adsorption processes were fitted to Langmuir isotherms. The adsorption behavior of CuFe2O4@PANI composite towards Hg2+ ions is attributed to the soft acid-soft base strong interaction between PANI and Hg(II) ions. High stability and enhanced re-usability are offered using CuFe2O4@PANI composite due to its enhanced removal efficiency. No significant removal decrease was noticed after five adsorption-desorption cycles. In addition, it possesses an easy removal from aqueous solutions by external magnetic field after adsorption experiments. These indicated the enhancement of polyaniline to the surface of CuFe2O4 toward the adsorption of mercury from aqueous solutions.


Assuntos
Compostos de Anilina/química , Cobre/química , Compostos Ferrosos/química , Mercúrio/química , Adsorção , Compostos Férricos , Concentração de Íons de Hidrogênio , Íons , Cinética , Mercúrio/toxicidade , Intoxicação por Mercúrio/prevenção & controle , Microscopia Eletrônica de Transmissão/métodos , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Termodinâmica , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Difração de Raios X/métodos
11.
Molecules ; 25(13)2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640703

RESUMO

A simple potentiometric sensor is described for accurate, precise, and rapid determination of sulfite additives in beverages. The sensor is based on the use of cobalt phthalocyanine as a recognition material, dispersed in a plasticized poly(vinyl chloride) matrix membrane. o-Nitrophenyl octyl ether (o-NPOE) as a membrane solvent and tri-dodecylmethyl- ammonium chloride (TDMAC) as ion discriminators are used as membrane additives. Under the optimized conditions, sulfite ion is accurately and precisely measured under batch and flow injection modes of analysis. The sensor exhibits fast and linear response for 1.0 × 10-2-1.0 × 10-6 M (800-0.08 µg/mL) and 1.0 × 10-1-5.0 × 10-5 M (8000-4 µg/mL) sulfite with Nernstian slopes of -27.4 ± 0.3 and -23.7 ± 0.6 mV/concentration decade under static and hydrodynamic modes of operation, respectively. Results in good agreement with the standard iodometric method are obtained.Validation of the assay method is examined in details including precision, accuracy, bias, trueness, repeatability, reproducibility, and uncertainty and good performance characteristics of the method are obtained. The sensor response is stable over the pH range of 5 to 7 without any significant interference from most common anions. The advantages offered by the proposed sensor (i.e., wide range of assay, high accuracy and precision, low detection limit, reasonable selectivity, long term response stability, fast response, and long life span and absence of any sample pretreatment steps) suggest its use in the quality control/quality assurance routine tests in beverages industries, toxicological laboratories and by inspection authorities.


Assuntos
Bebidas/análise , Técnicas de Química Analítica/métodos , Indóis/química , Compostos Organometálicos/química , Sulfitos/análise , Ânions , Éteres/química , Hidrodinâmica , Concentração de Íons de Hidrogênio , Limite de Detecção , Membranas Artificiais , Plastificantes/química , Potenciometria/métodos , Compostos de Amônio Quaternário/química , Reprodutibilidade dos Testes , Sulfitos/química
12.
Sensors (Basel) ; 19(18)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505891

RESUMO

Possible improvement of the performance characteristics, reliability and selectivity of solid-contact nitrate ion-selective electrodes (ISE) (SC/NO3--ISE) is attained by the application of a nitron-nitrate (Nit+/NO3-) ion association complex and inserting multi-walled carbon nanotubes (MWCNTs) as an ion-to-electron transducer between the ion sensing membrane (ISM) and the electronic conductor glassy carbon (GC) substrate. The potentiometric performance of the proposed electrode revealed a Nernstian slope -55.1 ± 2.1 (r² = 0.997) mV/decade in the range from 8.0 × 10-8-1 × 10-2 M with a detection limit of 2.8 × 10-8 (1.7 ng/mL). Selectivity, repeatability and reproducibility of the proposed sensors were considerably improved as compared to the coated disc electrode (GC/NO3--ISE) without insertion of a MWCNT layer. Short-term potential stability and capacitance of the proposed sensors were tested using a current-reversal chronopotentiometric technique. The potential drift in presence of a MWCNT layer decreased from 167 µVs-1 (i.e., in absence of MWCNTs) to 16.6 µVs-1. In addition, the capacitance was enhanced from 5.99 µF (in absence of MWCNTs) to 60.3 µF (in the presence of MWCNTs). The presented electrodes were successfully applied for nitrate determination in real samples with good accuracy.

13.
Molecules ; 24(5)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845715

RESUMO

Herein, a facile route leading to good single-walled carbon nanotubes (SWCNT) dispersion or poly (3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) based single-piece nanocomposite membrane is proposed for trace determination of Cu2+ ions. The single-piece solid contact Cu2+-selective electrodes were prepared after drop casting the membrane mixture on the glassy-carbon substrates. The prepared potentiometric sensors revealed a Nernstian response slope of 27.8 ± 0.3 and 28.1 ± 0.4 mV/decade over the linearity range 1.0 × 10-3 to 2.0 × 10-9 and 1.0 × 10-3 to 1.0 × 10-9 M with detection limits of 5.4 × 10-10 and 5.0 × 10-10 M for sensors based on SWCNTs and PEDOT/PSS, respectively. Excellent long-term potential stability and high hydrophobicity of the nanocomposite membrane are recorded for the prepared sensors due to the inherent high capacitance of SWCNT used as a solid contact material. The sensors exhibited high selectivity for Cu2+ ions at pH 4.5 over other common ions. The sensors were applied for Cu2+ assessment in tap water and different tea samples. The proposed sensors were robust, reliable and considered as appealing sensors for copper (II) detection in different complex matrices.


Assuntos
Calixarenos/química , Cobre/química , Ionóforos/química , Fenóis/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Cátions Bivalentes/química , Técnicas Eletroquímicas/métodos , Eletrodos , Concentração de Íons de Hidrogênio , Limite de Detecção , Membranas Artificiais , Estrutura Molecular , Nanocompostos/química , Nanotubos de Carbono/química , Polímeros/química , Poliestirenos/química , Sensibilidade e Especificidade
14.
Molecules ; 24(17)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466322

RESUMO

A series of Schiff bases 14-25 were designed and synthesized for evaluation of their antibacterial properties against multi-drug resistant bacteria (MDRB). The antibacterial activities of Schiff bases 14-25 showed that most of the synthesized compounds displayed a significant antibacterial activity. Assessment of in silico ADMET properties (absorption, distribution, metabolism, excretion and toxicity) of Schiff bases illustrates that all derivatives showed agreement to the Lipinski's rule of five. Further enzymatic assay aided by molecular docking study demonstrated that compound 18 is a potent inhibitor of staphylococcus aureus DNA gyrase and dihydrofolate reductase kinases. This study could be valuable in the discovery of new potent antimicrobial agents.


Assuntos
Antibacterianos/síntese química , Pirazóis/química , Bases de Schiff/síntese química , Staphylococcus aureus/enzimologia , Antibacterianos/química , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Simulação por Computador , DNA Girase/metabolismo , Antagonistas do Ácido Fólico/síntese química , Antagonistas do Ácido Fólico/química , Antagonistas do Ácido Fólico/farmacologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Bases de Schiff/química , Bases de Schiff/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Tetra-Hidrofolato Desidrogenase/metabolismo , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia
15.
Molecules ; 24(8)2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31003551

RESUMO

New reliable and robust potentiometric ion-selective electrodes were fabricated using poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) as the solid contact between the sensing membrane and electrical substrate for an acetylcholine (ACh) bioassay. A film of PEDOT/PSS was deposited on a solid carbon screen-printed platform made from ceramic substrate. The selective materials used in the ion-selective electrode (ISE) sensor membrane were acetylcholinium tetraphenylborate (ACh/TPB/PEDOT/PSS-ISE) (sensor I) and triacetyl-ß-cyclodextrin (ß-CD/PEDOT/PSS-ISE) (sensor II). The sensors revealed clear enhanced Nernstian response with a cationic slope 56.4 ± 0.6 and 55.3 ± 1.1 mV/decade toward (ACh+) ions over the dynamic linear range 1.0 × 10-6-1 × 10-3 and 2.0 × 10-6-1.0 × 10-3 M at pH 5 with limits of detection 2.0 × 10-7 and 3.2 × 10-7 M for sensors I and II, respectively. The selectivity behavior of both sensors was also tested and the sensors showed a significant high selectivity toward ACh+ over different common organic and inorganic cations. The stability of the potential response for the solid-contact (SC)/ISEs was evaluated using a chronopotentiometric method and compared with that of electrodes prepared without adding the solid-contact material (PEDOT/PSS). Enhanced accuracy, excellent repeatability, good reproducibility, potential stability, and high selectivity and sensitivity were introduced by these cost-effective sensors. The sensors were also used to measure the activity of acetylcholinesterase (AChE). A linear plot between the initial rate of the hydrolysis of ACh+ substrate and enzyme activity held 5.0 × 10-3-5.2 IU∙L-1 of AChE enzyme. Application to acetylcholine determination in human serum was done and the results were compared with the standard colorimetric method.


Assuntos
Acetilcolina/sangue , Acetilcolinesterase/sangue , Técnicas Biossensoriais/métodos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Carbono/química , Neurotransmissores/sangue , Polímeros/química , Poliestirenos/química , Impressão , Análise de Injeção de Fluxo , Humanos , Hidrodinâmica , Hidrólise , Cinética , Potenciometria , Água/química
16.
Molecules ; 24(13)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261939

RESUMO

Breast cancer is considered the most common and deadly cancer among women worldwide. Nanomedicine has become extremely attractive in the field of cancer treatment. Due to the high surface to volume ratio and other unique properties, nanomaterials can be specifically targeted to certain cells and tissues to interact with the living systems. The strategic planning of this study is based on using the nanoprecipitation method to prepare nanoparticles BZP-NPs (3.8-5.7 nm) of the previously prepared benzofuran-pyrazole compound (IV) BZP which showed promising cytotoxic activity. The capacity of BZP and BZP-NPs to suppress the growth of human breast tumor MCF-7 and MDA-MB-231 cells was evaluated using MTT assay. The IC50 doses of BZP and BZP-NPs targeting normal breast cells MCF-12A exceeded those targeting the cancer cells by >1000-fold, demonstrating their reasonable safety profiles in normal cells. Furthermore, cell cycle analysis, apoptosis induction detection, assessment of p53, Bcl-2, caspase-3, and PARP-1 levels of BZP and its nano-sized-BZP-NPs particles were also evaluated. Although the obtained results were in the favor of compound IV in its normal-sized particles, BZP-NPs appeared as a hit compound which showed improved cytotoxicity against the tested human breast cancer cells associated with the induction of pre-G1 apoptosis as well as cell cycle arrest at G2/M phase. The increase in caspase-3 level, upregulation of p53, and downregulation of Bcl-2 protein expression levels confirmed apoptosis. Furthermore, ELISA results exhibited that BZP-NPs produced a more favorable impact as a PARP-1 enzyme inhibitor than the parent BZP.


Assuntos
Benzofuranos/síntese química , Neoplasias da Mama/enzimologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/síntese química , Pirazóis/síntese química , Benzofuranos/química , Benzofuranos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Feminino , Humanos , Células MCF-7 , Microscopia Eletrônica de Transmissão , Nanopartículas , Tamanho da Partícula , Inibidores de Poli(ADP-Ribose) Polimerases/química , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Pirazóis/química , Pirazóis/farmacologia
17.
Molecules ; 24(11)2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31146483

RESUMO

A series of 16-(α-alkoxyalkane)-17-hydrazino-estra-1(10),2,4-trien[17,16-c]-3-ol (3a-l) and estra-1(10),2,4-trien-[17,16-c]pyrazoline-3-ol derivatives (4a-d) were synthesized from corresponding arylidines 2a,b which was prepared from estrone 1 as starting material. Condensation of 1 with aldehydes gave the corresponding arylidine derivatives 2a,b which were treated with hydrazine derivatives in alcohols to give the corresponding derivatives 3a-l, respectively. Additionally, treatment of 2a,b with methyl- or phenylhydrazine in ethanolic potassium hydroxide afforded the corresponding N-substituted pyrazoline derivatives 4a-d, respectively. All these derivatives showed potent anti-ovarian cancer both in vitro and in vivo. The mechanism of anti-ovarian cancer was suggested to process via topoisomerase II and V600EBRAF inhibition.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Estrona/química , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Modelos Animais de Doenças , Estrona/análogos & derivados , Feminino , Humanos , Camundongos , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Inibidores da Topoisomerase II/química , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Molecules ; 24(6)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30889918

RESUMO

A new series of 5-(3,5-dinitrophenyl)-1,3,4-thiadiazole derivatives were prepared and evaluated for their in vitro antimicrobial, antitumor, and DHFR inhibition activity. Compounds 9, 10, 13, and 16 showed strong and broad-spectrum antimicrobial activity comparable to Amoxicillin and Fluconazole as positive antibiotic and antifungal controls, respectively. Compounds 6, 14, and 15 exhibited antitumor activity against four human cancer cell lines, CCRF-CEM leukemia, HCT-15 colon, PC-3 prostate, and UACC-257 melanoma cell lines using Doxorubicin as a reference drug. Compounds 10, 13, 14, and 15 proved to be the most active DHFR inhibitors with an IC50 range of 0.04 ± 0.82⁻1.00 ± 0.85 µM, in comparison with Methotrexate (IC50 = 0.14 ± 1.38 µM). The highly potent DHFR inhibitors shared a similar molecular docking mode and made a critical hydrogen bond and arene‒arene interactions via Ser59 and Phe31 amino acid residues, respectively.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Desenho de Fármacos , Simulação de Acoplamento Molecular , Tiadiazóis/química , Anti-Infecciosos/química , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
19.
Molecules ; 24(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30678347

RESUMO

A series of estrone derivatives 3⁻8 was designed and synthesized using estrone arylmethylenes 2a,b as starting materials and their structures were confirmed by different spectral data and elemental analyses. All the newly synthesized compounds exhibited potent in vitro and in vivo cytotoxic activities against breast cancer cell lines. In addition, all compounds were subjected to in vitro and in vivo inhibition assays for EGFR and VEGFR-2 kinases as well as p53 ubiquitination activity to obtain more details about their mechanism of action. Based on the promising results, a molecular docking study was investigated for the most representative compound 5a against the two targets, EGFR and VEGFR-2 kinases, to assess its binding affinity, hoping to rationalize and obtain potent anticancer agents in the future.


Assuntos
Antineoplásicos Hormonais/química , Antineoplásicos Hormonais/farmacologia , Desenho de Fármacos , Estrogênios/química , Estrogênios/farmacologia , Modelos Moleculares , Animais , Antineoplásicos Hormonais/síntese química , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Estrogênios/análogos & derivados , Estrogênios/síntese química , Feminino , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Relação Quantitativa Estrutura-Atividade , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
J Enzyme Inhib Med Chem ; 33(1): 978-988, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29792357

RESUMO

Dihydropyrimidinone derivatives containing piperidine moiety were synthesised in a good yield. All the compounds were confirmed by elemental analysis and spectral data. Anti-ulcer activity of novel dihydropyrimidinone-piperidine hybrids (1-18) was evaluated. Among them, four compounds (3, 8, 11 and 15) were found to be most active in 80% ethanol-induced ulcer experimental animal model. All the potent compounds were further evaluated for anti-ulcer activity by different in vivo anti-ulcer models to study the effect of compounds on anti-secretory and cytoprotective activities. All the active compounds inhibited the formation of gastric ulcers and increased the formation of gastric mucin secretion. Compound 15 was found to be the most potent compound of the series as anti-ulcer agent. Additional experimental studies on lead compound 15 will result in a new class of orally active molecule for anti-ulcer activity.


Assuntos
Antiulcerosos/síntese química , Antiulcerosos/uso terapêutico , Piperidinas/uso terapêutico , Pirimidinonas/uso terapêutico , Úlcera Gástrica/tratamento farmacológico , Animais , Antiulcerosos/química , Cristalografia por Raios X , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Etanol/administração & dosagem , Modelos Moleculares , Estrutura Molecular , Piperidinas/química , Pirimidinonas/síntese química , Pirimidinonas/química , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Relação Estrutura-Atividade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA