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1.
Sci Rep ; 13(1): 20421, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37989862

RESUMEN

The physicochemical properties of materials change significantly in nanometer dimensions. Therefore, several methods have been proposed for the synthesis of nanoparticles. Plant extracts and essential oils are applied as natural and economic resources to prepare nanomaterials especially metal nanoparticles. In this project, a green, simple and efficient method has been designed for the synthesis of Cu nanoparticles using Purple cabbage extract as a reducing and stabilizing agent. They were successfully loaded onto a new Ag complex containing 1,3,5-triazine Schiff base as ligand to form Cu@Ag-CPX nanocomposite. Phytochemical contents of extract were identified by standard qualitative analyses. The chemical structure of all synthesized compounds was characterized using spectral data. In FT-IR, coordination of C=N bond of Schiff base ligand to Ag+ ions shifted the absorption band from 1641 to 1632 cm-1. The UV-Vis spectrum of Cu@Ag-CPX nanocomposite shown the peak related to Cu nanoparticles in the region of around 251 nm. 5:7 molar ratio of Cu to Ag in Cu@Ag-CPX was determined using ICP-OES. The FESEM, TEM, and DLS techniques provided valuable insights into the morphology and size distribution of the nanocomposite, revealing the presence of rods and monodispersed particles with specific diameter ranges. These analyses of the nanocomposite displayed rods with diameters from 40 to 62 nm as well as monodispersed and uniform particles with average diameter of 45 nm, respectively. The presence of elements including carbon, nitrogen, oxygen, Cu and Ag was proved by EDX-EDS analysis. The XRD pattern of Cu@Ag-CPX shown the diffraction peaks of Cu and Ag particles at 2θ values of 10°-80°, and confirmed its crystalline nature. The inhibitory properties of the synthesized compounds were evaluated in vitro against four Gram-negative and two Gram-positive bacteria, as well as two fungal strains. The MIC, MBC and MFC values obtained from microdilution and streak plate sensitivity tests were ranged from 128 to 4096 µg ml-1. While Cu nanoparticles and Ag complexes were effective against some pathogens, they were not effective against all them. However, the growth of all tested microbial strains was inhibited by Cu@Ag-CPX nanocomposite, and makes it as a new promising antimicrobial agent. Modification of nanocomposite in terms of nanoparticle and complex can improve its blocking activities.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Espectroscopía Infrarroja por Transformada de Fourier , Bases de Schiff/química , Ligandos , Antiinfecciosos/farmacología , Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Antibacterianos/química , Pruebas de Sensibilidad Microbiana
2.
Helicobacter ; 28(5): e13004, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37391943

RESUMEN

Nano-structure Cu(II) complex [Cu(AMAB)2 ]Cl2 with Schiff base (AMAB) derived from the condensation between 4-(dimethylamino)benzaldehyde and amoxicillin trihydrate was prepared. (AMAB) Schiff base and its Cu(II) complex were identified and confirmed by different physicochemical techniques. The Schiff base (AMAB) was coordinated to copper ion through carbonyl oxygen and imine nitrogen donor sites. X-ray powder diffraction shows a cubic crystal system of the Cu(II) complex. The density functional theory was used to optimize the structure geometries of the investigated compounds. The molecular docking of the active amino acids of the investigated proteins' interactions with the tested compounds was evaluated. The bactericidal or bacteriostatic effect of the compounds was screened against some bacterial strains. The activity of Cu-chelate against Gram-negative bacteria was mainly more effective than its (AMAB) ligand and vice versa in the case of Gram-positive bacteria. The biological activity of the prepared compounds with biomolecules calf thymus DNA (CT-DNA) was determined by electronic absorption spectra and DNA gel electrophoresis technique. All studies revealed that the Cu-chelate derivative exhibited better binding affinity to both CT-DNA than the AMAB and amoxicillin itself. The anti-inflammatory effect of the designed compounds was determined by testing their protein denaturation inhibitory activity spectrophotometrically. All obtained data supported that the designed nano-Cu(II) complex with Schiff base (AMAB) is a potent bactericide against H. pylori, and exhibits anti-inflammatory activity. The dual inhibition effects of the designed compound represent a modern therapeutic approach with extended spectrum of action. Therefore, it can act as good drug target in antimicrobial and anti-inflammtory therapies. Finally, H. pylori resistance to amoxicillin is absent or rare in many countries, thus amoxicillin nanoparticles may be beneficial for countries where amoxicillin resistance is reported.


Asunto(s)
Antiinfecciosos , Infecciones por Helicobacter , Helicobacter pylori , Humanos , Helicobacter pylori/metabolismo , Bases de Schiff/farmacología , Bases de Schiff/química , Cobre/farmacología , Cobre/química , Amoxicilina/farmacología , Simulación del Acoplamiento Molecular , Infecciones por Helicobacter/tratamiento farmacológico , Antiinfecciosos/farmacología , Antibacterianos/farmacología , Antibacterianos/química , ADN/química , ADN/metabolismo , Pruebas de Sensibilidad Microbiana
3.
J Enzyme Inhib Med Chem ; 38(1): 2232125, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37403517

RESUMEN

Nanotechnology-based strategies can overcome the limitations of conventional cancer therapies. Hence, novel series of pyrimidine Schiff bases (4-9) were employed in the synthesis of selenium nanoparticle forms (4NPs-9NPs). All selenium nano-sized forms exerted greater inhibitions than normal-sized compounds, far exceeding 5-fluorouracil activity. Compound 4 showed effective anti-proliferative activity against MCF-7(IC50 3.14 ± 0.04 µM), HepG-2(IC50 1.07 ± 0.03 µM), and A549(IC50 1.53 ± 0.01 µM) cell lines, while its selenium nanoform 4NPs showed excellent inhibitory effects, with efficacy increased by 96.52%, 96.45%, and 93.86%, respectively. Additionally, 4NPs outperformed 4 in selectivity against the Vero cell line by 4.5-fold. Furthermore, 4NPs exhibited strong inhibition of CDK1(IC50 0.47 ± 0.3 µM) and tubulin polymerase(IC50 0.61 ± 0.04 µM), outperforming 4 and being comparable to roscovitine (IC50 0.27 ± 0.03 µM) and combretastatin-A4(IC50 0.25 ± 0.01 µM), respectively. Moreover, both 4 and 4NPs arrested the cell cycle at G0/G1 phase and significantly forced the cells towards apoptosis. Molecular docking demonstrated that 4 and 4NPs were able to inhibit CDK1 and tubulin polymerase binding sites.


Asunto(s)
Antineoplásicos , Selenio , Relación Estructura-Actividad , Antineoplásicos/química , Selenio/farmacología , Tubulina (Proteína)/metabolismo , Simulación del Acoplamiento Molecular , Proliferación Celular , Bases de Schiff/química , Línea Celular Tumoral , Pirimidinas/química , Ensayos de Selección de Medicamentos Antitumorales , Estructura Molecular
4.
Environ Sci Pollut Res Int ; 30(49): 106790-106811, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36334198

RESUMEN

Three new cross-linked chitosan derivatives were yielded through intensification of chitosan with diverse types of bis-aldehydes. The prepared cross-linked chitosan was characterized by FTIR, 1H NMR, XRD, and TGA techniques. TGA indicated an improvement in thermal stability of the cross-linked chitosan compared with pure chitosan. Batch adsorption experiments showed that the three novel cross-linked chitosan bis-aldehyde derivatives possessed good adsorption capacity against U(VI) in the order of BFPA > BFB > BODB (adsorption capacity of the three adsorbents for U(VI) reaches 142, 124, and 114 mg/g respectively) and the adsorption isotherm and kinetic were well described by the Langmuir and the pseudo-second-order kinetic model, respectively. In addition, the prepared cross-linked chitosan bis-aldehyde derivatives were examined as U(VI) catcher from waste solutions.


Asunto(s)
Quitosano , Uranio , Contaminantes Químicos del Agua , Quitosano/química , Uranio/química , Bases de Schiff/química , Agua , Adsorción , Cinética , Contaminantes Químicos del Agua/química , Aldehídos , Concentración de Iones de Hidrógeno , Soluciones
5.
Int J Biol Macromol ; 194: 611-618, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34822818

RESUMEN

In this work, a novel sustained released system (VCSB-Zn(II)) for zinc supplements was built by vanillin-chitosan Schiff base (VCSB) chelated with Zn2+ to improve the zinc trace element utilization ratio. Samples were characterized by FT-IR, 1H NMR, XRD, SEM, and TGA. The results showed that VCSB exhibited a more excellent chelation capacity of Zn2+ than chitosan. The chelation capacity of VCSB was about 1.7 times more than that of chitosan, corresponding to 50.96 mg/g and 29.91 mg/g, respectively. Furthermore, VCSB-Zn(II) showed excellent sustained released performance at simulated gastric fluid because of the acid slow-dissolving ability. And the higher the CN content of VCSB, the higher the cumulative release rate (Ri) of Zn2+, the highest Ri reached 77.81%. The sustained released curves were described by the first-order and Korsmeyer-Peppas equation, which described the Zn2+ sustained released performance caused by the dissolution of VCSB-Zn(II) and Fick diffusion. This Zn2+ sustained released system shows great potential in the application in the field of trace elements supplements for animals.


Asunto(s)
Benzaldehídos/química , Quitosano/química , Zinc/química , Liberación de Fármacos , Bases de Schiff/química
6.
Molecules ; 26(11)2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34071327

RESUMEN

Chitosan is the only cationic polysaccharide in nature. It is a type of renewable resource and is abundant. It has good biocompatibility, biodegradability and biological activity. The amino and hydroxyl groups in its molecules can be modified, which enables chitosan to contain a variety of functional groups, giving it a variety of properties. In recent years, researchers have used different strategies to synthesize a variety of chitosan derivatives with novel structure and unique activity. Structure combination is one of the main strategies. Therefore, we will evaluate the synthesis and agricultural antimicrobial applications of the active chitosan derivatives structure combinations, which have not been well-summarized. In addition, the advantages, challenges and developmental prospects of agricultural antimicrobial chitosan derivatives will be discussed.


Asunto(s)
Antiinfecciosos/química , Materiales Biocompatibles/química , Quitosano/química , Productos Agrícolas , Polisacáridos/química , Aldehídos/química , Antifúngicos/química , Protección de Cultivos , Iones , Cetonas/química , Fósforo/química , Enfermedades de las Plantas/prevención & control , Bases de Schiff/química , Azufre/química
7.
ACS Appl Bio Mater ; 4(1): 428-440, 2021 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35014294

RESUMEN

A layer-by-layer (L-B-L) bacterial cellulose (BC)-based transdermal patch has been prepared via a Schiff base reaction. The L-B-L assembly consisting of covalently cross-linked ethylene diamine-modified carboxymethylated BC isolated from the Glucanoacetobacter xylinus (MTCC7795) bacterial strain and aldehyde-modified pectin formed via a Schiff base reaction. The presence of the imine bond assists the self-healing process after being scratched in the presence of a pH 7.4 buffer solution monitored via optical microscopy, atomic force microscopy, and tensile strength analyses. The formation of the L-B-L assembly was confirmed using field-emission scanning electron microscopy (FESEM) analysis. Simultaneously, water swelling and deswelling studies were carried out to test its water retention efficiency. The presence of silver nanoparticles (AgNPs) has been confirmed by ultraviolet-visible spectroscopy and FESEM analyses. The antimicrobial activity of the AgNPs-incorporated transdermal patch has been examined over Staphylococcus aureus and Escherichia coli using the zone of inhibition method. Additionally, the cell viability assay was performed using the fluorescent dyes 4',6-diamidino-2-phenylindole and propidium iodide. The AgNPs in the L-B-L assembly showed antimicrobial property against both types of bacteria. The cytotoxicity and wound healing property of the patch system have been studied over NIH 3T3 fibroblast and A549 epithelial cell lines. The L-B-L film also influenced the wound healing process of these two cell lines.


Asunto(s)
Antiinfecciosos/química , Celulosa/química , Nanopartículas del Metal/química , Bases de Schiff/química , Plata/química , Animales , Antiinfecciosos/farmacología , Vendajes , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Gluconacetobacter xylinus/metabolismo , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Pectinas/química , Staphylococcus aureus/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos
8.
Molecules ; 25(24)2020 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-33339433

RESUMEN

Herein, we report the synthesis and characterization of a new Schiff base ligand 3-[[(E)-(3-hydroxyphenyl)-methylidene]amino]-2-methyl-quinazolin-4(3H)-one (HAMQ) and its Cd(II), Ni(II), Zn(II), and Cu(II) complexes (C1-C4). The ligand HAMQ was synthesized by reacting 3-hydroxybenzaldehyde and 3-amino-2-methyl-4(3H)-quinazolinone in a 1:1 molar ratio. The structure of the ligand and its complexes (C1-C4) were evaluated using ultraviolet (UV)-visible (Vis) light spectroscopy, 1H-NMR, Fourier-transform infrared (FT-IR) spectroscopy, MS, elemental analysis, conductance data, and thermogravimetric analysis (TGA). The characterization results suggested that the bidentate ligand, HAMQ, coordinated to the metal center through the lactum oxygen and the azomethine nitrogen. Moreover, all the metal complexes were analyzed using powder X-ray diffraction studies, which revealed that all of them belong to a triclinic crystal system. The research was supplemented by density functional theory (DFT) studies on the IR and UV-Vis spectra, as well as the chemical reactivity of the HAMQ and its four metallic derivatives making use of conceptual density functional theory (CDFT) by means of KID (Koopmans in DFT) methodology. The synthesized complexes displayed significant in vitro anticancer activity against human cancer cell lines (HeLa and HCT-115).


Asunto(s)
Antineoplásicos/química , Complejos de Coordinación/química , Quinazolinonas/química , Bases de Schiff/química , Antineoplásicos/farmacología , Cadmio/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Complejos de Coordinación/farmacología , Cobre/química , Teoría Funcional de la Densidad , Humanos , Ligandos , Níquel/química , Espectrofotometría , Espectroscopía Infrarroja por Transformada de Fourier , Zinc/química
9.
Food Chem ; 302: 125336, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31419772

RESUMEN

This study reports a stepwise optimization of switchable liquid-liquid microextraction (SLLME) for cobalt determination by flame atomic absorption spectrometry (FAAS) coupled with a slotted quartz tube (SQT). The main purpose of this study was to develop an accurate and sensitive analytical method for cobalt. Extraction method was used to separate and preconcentrate cobalt from sage tea and vitamin B12 samples after complexing with a Schiff base ligand. 107.7 folds enhancement in detection power under the optimum conditions was recorded with respect to direct FAAS. This enhancement correlated to 3.1 µg/L limit of detection and 10 µg/L limit of quantification. The SLLME-SQT-FAAS method was linear over a broad concentration range and low %RSD values established high precision for the method. Appreciable percent recovery results (94-108%) obtained from spiked sage sample and from cobalamin also validated the accuracy of the method.


Asunto(s)
Cobalto/análisis , Microextracción en Fase Líquida/métodos , Espectrofotometría Atómica/métodos , Tés de Hierbas/análisis , Vitamina B 12/análisis , Límite de Detección , Cuarzo , Reproducibilidad de los Resultados , Salvia officinalis/química , Bases de Schiff/química , Espectrofotometría Atómica/instrumentación , Vitamina B 12/química
10.
Biopolymers ; 111(3): e23338, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31696516

RESUMEN

A chitosan Schiff base with an aromatic aldehyde was synthesized and characterized by FTIR and NMR spectroscopies. Furthermore, the degree of substitution was calculated based on the ratios of the area of the proton of the imine (Aimine ) and the area of the peak of the proton of the pyranose ring (AH-2 ). The antimicrobial activities were determined against bacterial and fungal strains, as well as multiple drug-resistant (MDR) bacteria. The chitosan Schiff base was also tagged with medicinal plants, for example, Curcuma longa, Peganum harmala, Lepidium sativam, and cruciferous vegetables, and the biological activities determined against pathogenic bacterial and fungal strains. The chitosan Schiff base showed maximum zone of inhibition of 22 mm against Staphylococcus aureus with a minimum zone of inhibition of 15 mm against Bacillus cereus. The chitosan Schiff base was fused with C longa, isothiocyanates and a combined mixture of P harmala and L sativam that has shown activities against Escherichia coli with a zone of inhibition of 28, 24, and 30 mm, respectively. The Schiff base of chitosan fused with medicinal plants also showed significant inhibitory activities against MDR bacteria.


Asunto(s)
Antiinfecciosos/química , Quitosano/química , Extractos Vegetales/química , Plantas Medicinales/química , Bases de Schiff/química , Antiinfecciosos/farmacología , Bacillus cereus/efectos de los fármacos , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana/efectos de los fármacos , Hongos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Modelos Químicos , Estructura Molecular , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos
11.
Int J Biol Macromol ; 140: 588-599, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31442510

RESUMEN

A novel superoleophilic-hydrophobic nonanyl chitosan-poly (butyl acrylate) grafted copolymer was fabricated as a low-cost oil-adsorbent. Chitosan (CS) was coupled with a hydrophobic nonanal (N) to form nonanyl chitosan (NCS) schiff base, and followed by grafting with butyl acrylate monomers (ButA). The grafted copolymer was characterized by FTIR, TGA and SEM tools. The grafting percent was augmented and reached 88.5% with increasing ButA concentration up to 156 mM. Moreover, measurements of contact angle proved the superoleophilic character of NCS-g-poly (ButA) copolymer with an oil-contact angle 31°. Factors affecting the removal process such as contact time, oil type, oil dose, adsorbent dose, temperature and agitation speed were optimized. An increment in the oil removal (%) was observed with increasing the oil viscosity in the order of gasoil < mobil-1 oil < light crude oil < heavy crude oil. Besides, the adsorption process followed the pseudo-second order model and the equilibrium data were sufficiently fitted with the Langmuir model with a maximum adsorption capacity 108.79 g/g at 25 °C. Thermodynamic parameters computed from Van't Hoff plot confirmed the process to be exothermic, favorable and spontaneous. The results nominate the superoleophilic adsorbent as a potential oil- adsorbent for petroleum oil spills removal.


Asunto(s)
Acrilatos/química , Quitosano/química , Contaminación por Petróleo/efectos adversos , Petróleo/análisis , Polímeros/química , Adsorción , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Bases de Schiff/química , Temperatura , Termodinámica
12.
Pak J Pharm Sci ; 32(3): 963-967, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31278707

RESUMEN

A new series of copper (II), cobalt (II), zinc (II), nickel (II), manganese (II), iron (II) complexes with a novel Schiff base were synthesized by the condensation of sulphadizine and thiophene-2-carbaldehyde.The ligand and its complexes were characterized by using diverse instrumental procedures like microanalysis, thermo gravimetric examination and spectroscopy. The integrated ligand and its metal complexes were subjected to antibacterial studies. These studies demonstrated the enhanced activity of metal complexes against reported microbes with respect to the Schiff base.


Asunto(s)
Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacología , Metales/química , Antiinfecciosos/química , Bacillus pumilus/efectos de los fármacos , Clostridium butyricum/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Enterobacter aerogenes/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Klebsiella oxytoca/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Bases de Schiff/química , Staphylococcus aureus/efectos de los fármacos , Tiofenos/química
13.
Chem Commun (Camb) ; 55(44): 6269-6272, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31086908

RESUMEN

Porphyrin-based covalent organic polymer nanoparticles were synthesized via a Schiff base reaction at room temperature. The resulting product showed a good photodynamic effect and a high photothermal conversion efficiency (34.88%). Both in vitro and in vivo experiments demonstrated the enhanced antitumor efficacy via synergistic photodynamic and photothermal therapy.


Asunto(s)
Antineoplásicos/farmacología , Nanopartículas , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Fototerapia/métodos , Polietilenglicoles/farmacología , Porfirinas/farmacología , Animales , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Células HeLa , Humanos , Ratones , Microscopía Electrónica de Rastreo , Fármacos Fotosensibilizantes/química , Porfirinas/química , Difracción de Polvo , Bases de Schiff/química , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Int J Biol Macromol ; 127: 232-239, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30641193

RESUMEN

One of the most important problems in catalytic systems is metal leaching due to weak interactions between the supporting material and the metal ions. It adversely affects the reusability and catalytic performance of catalysts. In this study, a novel support material, which is a composed Schiff base functionalized pectin bio-polymer with good coordination performance against palladium ions, was designed and characterized to overcome the afore-mentioned problems. Then the catalytic activity of the designed pectin supported palladium catalyst (Pct-Pd) was evaluated in Suzuki-Miyaura coupling reactions. Pct-Pd catalyst provided excellent conversion yields in the reactions within 8 min. Additionally, Pct-Pd catalyst displayed superior reproducibility by giving 91% of conversion yield after 12 successive runs. Leaching test revealed that leaching of palladium ions from prepared support was negligible even after 12 runs. This study shows that the designed Pct-Pd catalyst can be transferred from academic laboratory to industrial applications due to its excellent reusability and catalytic activity.


Asunto(s)
Microondas , Paladio/química , Pectinas/química , Bases de Schiff/química
15.
J Inorg Biochem ; 191: 183-193, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30530179

RESUMEN

Alzheimer's disease (AD) is one of the most common age-related neurodegenerative disorders. Aggregation of amyloid-ß peptide into extracellular plaques with incorporation of metal ions, such as Cu2+, and reduction of the neurotransmitter acetylcholine levels are among the factors associated to the AD brain. Hence, a series of 7-chloro-4-aminoquinoline Schiff bases (HLa-e) were synthesized and their cytotoxicity and anti-cholinesterase activity, assessed for Alzheimer's disease. The intrinsic relationship between Cu2+ and the amyloidogenic plaques encouraged us to investigate the chelating ability of HLa-e. Dimeric tetracationic compounds, [Cu2(NHLa-e)4]Cl4, containing quinoline protonated ligands were isolated from the reactions with CuCl2·2H2O and fully characterized in the solid state, including an X ray diffraction study, whereas EPR data showed that the complexes exist as monomers in DMSO solution. The inhibitory activity of all compounds was evaluated by Ellman's spectrophotometric method in acetylcholinesterase (AChE) from Electrophorus electricus and butyrylcholinesterase (BChE) from equine serum. HLa-e and [Cu(NHLd)2]Cl2 were selective for AChE (IC50 = 4.61-9.31 µM) and were not neurotoxic in primary brain cultures. Docking and molecular dynamics studies of HLa-e inside AChE were performed and the results suggested that these compounds are able to bind inside AChE similarly to other AChE inhibitors, such as donepezil. Studies of the affinity of HLd for Cu2+ in DMSO/HEPES at pH 6.6 and pH 7.4 in µM concentrations showed formation of analogous 1:2 Cu2+/ligand complexes, which may suggest that in the AD-affected brain HLd may scavenge Cu2+ and the complex, also inhibit AChE.


Asunto(s)
Aminoquinolinas/química , Inhibidores de la Colinesterasa/farmacología , Complejos de Coordinación/farmacología , Cobre/química , Bases de Schiff/química , Animales , Células Cultivadas , Inhibidores de la Colinesterasa/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacocinética , Evaluación Preclínica de Medicamentos , Técnicas In Vitro , Ratones , Simulación del Acoplamiento Molecular , Análisis Espectral/métodos
16.
Acta Chim Slov ; 65(2): 416-428, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29993095

RESUMEN

Two novel copper(II) Schiff base complexes were synthesized and characterized by various physico-chemical and spectroscopic methods, revealing a distorted square planar geometry around the copper atom. The analytical data confirmed the 1:1 metal to ligand stoichiometry of the complexes. B3LYP/(LANL2DZ/6-311G**) density functional theory (DFT) were used to investigate structural and electronic properties of the synthesized compounds in gas phase. The computational results support the conclusion obtained by the experimental studies. Thermodynamic study of complex formation in solution was carried out spectrophotometrically at 25 °C. These compounds were also subjected to study in vitro antibacterial screening against some bacteria. Also, click reaction was investigated for its catalytic properties. The synthesized Schiff base copper complexes catalyzed 1,3-dipolar Huisgen cycloaddition of different functionalized ?-azido alcohols and alkynes in the presence of ascorbic acid in a solution of THF/H2O (2:1, V/V) at room temperature.


Asunto(s)
Antibacterianos/química , Complejos de Coordinación/química , Cobre/química , Bases de Schiff/química , Catálisis , Evaluación Preclínica de Medicamentos/métodos , Escherichia coli/efectos de los fármacos , Ligandos , Modelos Moleculares , Estructura Molecular , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Termodinámica
17.
Anal Chem ; 90(6): 4119-4125, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29466857

RESUMEN

Selenocysteine (Sec) is a primary kind of reactive selenium species in cells, and its vital roles in physiological processes have been featured. Thus, the development of highly sensitive and selective methods for the sensing of Sec is of great significance. This work reports a turn-on fluorescent probe for selenol based on the unique fluorescence OFF-ON switching between the Schiff base (SB) and its complementary protonated Schiff base (PSB) form of merocyanine dyes. The probe consists of a merocyanine Schiff base fluorophore and a 2,4-dinitrobenzenesulfonamide moiety that reacts especially with selenol. The fluorescence turn-on response of MC-Sec is realized via the selective removal of the strongly electron withdrawing 2,4-dinitrobenzenesulfonyl group by Sec, leading to a shift in the p Ka of the imine nitrogen of the probe from 6.40 to 9.04 and thus significantly increasing the population of the fluorescent PSB form of the dye at physiological pH. MC-Sec shows good selectivity and sensitivity for Sec and has been applied in the imaging of exogenous and endogenous selenol in living cells by confocal fluorescence microscopy. The proposed mechanism should be useful for developing future probes directed to other target molecules by employing this simple but effective p Ka shift strategy.


Asunto(s)
Benzopiranos/química , Colorantes Fluorescentes/química , Indoles/química , Imagen Óptica/métodos , Compuestos de Selenio/análisis , Línea Celular , Fluorescencia , Humanos , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Bases de Schiff/química , Espectrometría de Fluorescencia/métodos
18.
Comb Chem High Throughput Screen ; 21(3): 194-203, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29436997

RESUMEN

BACKGROUND: Malaria is one of the most vital infectious diseases caused by protozoan parasites of the Plasmodium genus. As P. falciparum, the cause of most of the severe cases of malaria, is increasingly resistant to available drugs such as amodioquine, chloroquine, artemisinin, and antifolates, there is an urgent need to identify new targets for chemotherapy. OBJECTIVE: This study screened novel pyrazole derivatives carrying iminium & benzothiazole group for antimalarial potential against P. falciparum chloroquine sensitive (3D7) strain. MATERIALS & METHODS: Several pyrazole schiff base hybrids with a wide range of substitution have been synthesized via condensation of substituted aniline with substituted 4-formylpyrazole and evaluated for their in vitro antimalarial activity against asexual blood stages of human malaria parasite, Plasmodium falciparum. The interaction of these conjugate hybrids was also investigated by molecular docking studies in the binding site of P. falciparum cystein protease falcipain-2. The pharmacokinetic properties were also studied using ADME prediction. RESULTS: Among all compounds, 6bf and 6bd were found to be potential molecules with EC50 1.95µg/ml and 1.98µg/ml respectively. Docking study results reveal that the pyrazole schiff base derivatives occupy the PfFP binding sites and they show good interactions with significant values of binding energies. CONCLUSION: We provide evidence which implicates pyrazole Schiff base hybrids as potential prototypes for the development of antimalarial agents.


Asunto(s)
Antimaláricos/síntesis química , Pirazoles/uso terapéutico , Bases de Schiff/uso terapéutico , Antimaláricos/metabolismo , Benzotiazoles/química , Biología Computacional , Cisteína Endopeptidasas/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Iminas/química , Simulación del Acoplamiento Molecular , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/enzimología , Pirazoles/química , Bases de Schiff/química
19.
Int J Biol Macromol ; 110: 215-226, 2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29169947

RESUMEN

O-Carboxymethyl chitosan (OCMC) Schiff's base was utilized for a new class of organic-inorganic hybrid material by grafting it on nano-silica-silane and further metallated with Cu (II). Here (3-Aminopropyl) triethoxysilane (APTES) was used as a linker and 2-hydroxy-1-naphthaldehyde (HN) for Schiff's base formation. The hybrid was characterized by FTIR, TGA, powder XRD, SEM, CHN, DLS, ICP-AES, diffuse reflectance UV-vis and EDX spectroscopic techniques. Magnetization measurements were carried out by VSM at room temperature. This study explored the possible synergic effect of unique properties of carboxymethyl chitosan, Schiff's base Cu (II) complex and nano-silica towards antibacterial activity and in dye degradation studies. The antibacterial performance of nano-hybrid material was examined against both Gram-positive (Escherichia coli) and Gram-negative (Bacillus subtilis) bacteria. The catalytic activity of the hybrid was tested for degradation of reactive black 5 (RB5) through advanced oxidation processes using H2O2 as oxidant. The results show a high dye degradation efficiency of 93% in 130min by the hybrid catalyst with reusability. As per published reports, Chitosan-Schiff's bases show strong antimicrobial activity and their Cu complexes exhibit good catalytic and anticancer activities. Therefore, it is expected that the new organic-inorganic hybrid would be highly applicable in environmental as well as biomedical fields.


Asunto(s)
Antibacterianos , Bacillus subtilis/crecimiento & desarrollo , Bisfenol A Glicidil Metacrilato , Cobre , Medicamentos Herbarios Chinos , Escherichia coli/crecimiento & desarrollo , Nanopartículas/química , Dióxido de Silicio , Antibacterianos/química , Antibacterianos/farmacología , Bisfenol A Glicidil Metacrilato/química , Bisfenol A Glicidil Metacrilato/farmacología , Cobre/química , Cobre/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Bases de Schiff/química , Bases de Schiff/farmacología , Dióxido de Silicio/química , Dióxido de Silicio/farmacología
20.
J Agric Food Chem ; 65(40): 8773-8778, 2017 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-28942637

RESUMEN

2-Hydroxy-4-methoxybenzaldehyde (HMBA) is a nontoxic phenolic flavor from dietary source Decalipus hamiltonii and Hemidesmus indicus. HMBA is an excellent antimicrobial agent with additional antiaflatoxigenic potency. On the other hand, cinnamaldehyde from cinnamon is a widely employed flavor with significant antiaflatoxigenic activity. We have attempted the enhancement of antiaflatoxigenic and antimicrobial properties of HMBA, cinnamaldehyde, and similar molecules via Schiff base formation accomplished from condensation reaction with amino sugar (d-glucamine). HMBA derived Schiff bases exhibited commendable antiaflatoxigenic activity at the concentration 0.1 mg/mL resulting in 9.6 ± 1.9% growth of Aspergillus flavus and subsequent 91.4 ± 3.9% reduction of aflatoxin B1 with respect to control.


Asunto(s)
Acroleína/análogos & derivados , Antifúngicos/farmacología , Apocynaceae/química , Aspergillus flavus/efectos de los fármacos , Benzaldehídos/farmacología , Cinnamomum zeylanicum/química , Hemidesmus/química , Extractos Vegetales/farmacología , Acroleína/química , Acroleína/farmacología , Aflatoxina B1/metabolismo , Aldehídos/química , Aldehídos/farmacología , Antifúngicos/química , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/metabolismo , Benzaldehídos/química , Estructura Molecular , Extractos Vegetales/química , Bases de Schiff/química , Bases de Schiff/farmacología
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