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1.
Inorg Chem ; 63(1): 576-592, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38110302

RESUMEN

Herein, we describe the solid-state fusion of rod-shaped to honeycomb-shaped cadmium oxide particles (CdO NPs) caused by the process of repeated exposure to acoustic shock waves. Significant changes have been observed in structurally and morphologically dependent properties. For instance, at the 200-shocked condition, the high-pressure CdO-B2 phase is present as a secondary phase wherein all of the rod-shaped particles have been transformed into honeycomb-shaped CdO particles which possess comparatively higher specific-capacitance than CdO nanorods (NRs). The computed specific capacitance values for the 0, 100, and 200 shocked samples at a scan rate of 100 m V s-1 are computed to be 433, 415, and 583 F g-1, respectively. The second-stage decomposition temperature points of the CdO NPs have significantly increased in accordance with the morphological changes from rod to honeycomb patterns such that the values are 343, 526, and 534 °C, respectively, for 0, 100, and 200 shocked conditions. Note that such honeycomb nanostructured CdO particles by shock-wave processing have never been observed, to date. Due to the superior energy storage abilities as well as the spectacular high thermal stability of the honeycomb CdO nanostructures compared to CdO NRs, shocked CdO with honeycomb nanostructures can be considered as energy storage materials.

2.
J Phys Chem A ; 128(16): 3095-3107, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38600671

RESUMEN

In this context, we have reexamined the acoustical shock wave-induced amorphous-glassy-crystalline-amorphous phase transitions in the Li2SO4 sample under 0, 1, 2, and 3 shocked conditions by implementing the detailed Raman spectroscopic approach. The recorded Raman spectroscopic data clearly reveal that the transition from the amorphous-glassy-crystalline state occurs because of a significant reduction of the translational disorder of lithium cations, particularly [Li (2)] ions wherein a slight reduction of the librational disorder of SO4 anions takes place, whereas the crystalline to amorphous transition occurs only at the third shocked condition because of the librational disorder of SO4 anions. The double degenerate υ2 and υ4 Raman modes provide a clear indication of the occurrence of the librational disorder of SO4 anions at the third shocked condition. Followed by the internal Raman modes, a detailed discussion is provided on the external Raman modes of the Li ions and SO4 ions with respect to the observed phase transitions, wherein it is found that the regions of lattice modes are significantly altered at each and every point of phase transition. Furthermore, the thermal and magnetic measurements have been performed for the above-mentioned state of Li2SO4 samples, whereby the obtained results of the magnetic loops and the thermal property resemble the observed structural transitions with respect to the number of shock pulses such that the inter-relationship of the structure-electrical-magnetic-thermal properties of Li2SO4 could be explored.

3.
Environ Res ; 251(Pt 1): 118666, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38462087

RESUMEN

In the present scenario, food security is of major concern due to exponentially increasing population and depleted crop production. The fungal diseases have contributed majorly to the scarcity of staple food products and economic loss worldwide. This problem could be tackled by preventing the crop loss during both pre and post-harvest seasons. During the current investigation, the bioactive compound eicosane was extracted from Streptomyces sp. KF15, subjected to purification and identified based on mass spectrometry and NMR analysis. The evaluation of in-vitro antifungal activity was done by poisoned food method, SEM analysis and growth pattern analysis. The bioactive compound eicosane with molecular weight of 282.5475 g/mol was purified by column chromatography and the straight chain hydrocarbon structure of CH3CH2(18)CH3 was elucidated by NMR analysis. In poisoned food assay, eicosane effectively inhibited the radial growth of all tested fungal pathogens; F. oxysporum was found to be the most sensitive with 24.2%, 33.3%, 42.4%, and 63.6% inhibition at 25-100 µg/ml concentrations. The SEM micrograph established clear differences in the morphology of eicosane treated fungi with damaged hyphae, flaccid mycelium and collapsed spores as compared to the tubular, turgid and entire fungi in control sample. Finally, the growth curve assay depicted the right side shift in the pattern of eicosane treated fungi indicating the delay in adapting to the conditions of growth and multiplication. The findings of this study encourage further research and development towards the novel antifungal drugs that can act against major phytopathogens.


Asunto(s)
Antifúngicos , Streptomyces , Streptomyces/química , Antifúngicos/farmacología , Antifúngicos/química , Productos Agrícolas/microbiología , Fungicidas Industriales/farmacología , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología , Hongos/efectos de los fármacos
4.
Environ Res ; 257: 119288, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38823619

RESUMEN

The study aimed to analyze the pharmacological properties of medicinal plant Indigofera hochstetteri Baker extracts. Preliminary phytochemical analysis revealed a diverse range of secondary metabolites present in it. TLC analysis detected numerous phytochemicals with varying Rf values, aiding in different solvent systems. GC-MS analysis revealed the presence of 29 bioactive compounds with diverse pharmacological activities, including anti-inflammatory, antioxidant, analgesic and antimicrobial properties. Antimicrobial effect of I. hochstetteri Baker methanolic extract showed significant inhibitory effects against E. coli, E. aerogenes, S. flexneri, P. aeruginosa, S. aureus, E. faecalis, B. cereus, and fungal strain C. albicans. The methanol extract also showed significant antifungal activity by inhibiting the growth of Sclerotium rolfsii in food poisoning method. MTT assays revealed significant cytotoxic activity of methanolic extract against human leukemia HL-60 cancer cells with IC50 of 116.01 µg/mL. In apoptotic study, I. hochstetteri Baker methanolic extract showed 28.84% viable cells, 30.2% early apoptosis, 35.54% late apoptosis, and 5.86% necrosis comparatively similar with standard used. The extract showed significant anti-inflammatory effect on HRBC stabilization, and protein denaturation of BSA and egg albumin denaturation with IC50 of 193.62 µg/mL, 113.94 µg/mL respectively. In anti-diabetic assays like α-amylase, α-glucosidase, and Glucose uptake assay, I. hochstetteri extract showed good anti-diabetic effect with IC50 of 60.64 µg/mL, 169.34 µg/mL, and 205.63 µg/mL respectively. In conclusion I. hochstetteri Baker have promising bioactive metabolites with significant biological activities, it can be good substitute for the chemical drugs after successful clinical studies.

5.
Molecules ; 29(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38474443

RESUMEN

Employing naturally extracted dyes and their derivatives as photosensitizers towards the construction of dye-sensitized solar cells (DSSCs) has been recently emerging for establishing sustainable energy conversion devices. In this present work, Rhodobacter Sphaeroides Photobacteria (Rh. Sphaeroides) was used as a natural source from which Bacteriopheophytine-a (Bhcl) dye was extracted. Further, two cationic derivatives of Bhcl, viz., Guanidino-bacteriopheophorbide-a (Gua-Bhcl) and (2-aminoethyl)triphenylphosphono-bacteriopheophorbide-a (2AETPPh-Bhcl) were synthesized. The thus obtained Bhcl, Gua-Bhcl and 2AETPPh-Bhcl were characterized using liquid chromatography-mass spectrometry (LC-MS) and their photophysical properties were investigated using excitation and emission studies. All three near-infrared (NIR) responsive dyes were employed as natural sensitizers towards the construction of DSSC devices, using platinum as a photocathode, dye-sensitized P25-TiO2 as a photoanode and I-/I3- as an electrolyte. DSSCs fabricated using all three dyes have shown reasonably good photovoltaic performance, among which 2AETPPh-Bhcl dye has shown a relatively higher power conversion efficiency (η) of 0.38% with a short circuit photocurrent density (JSC) of 1.03 mA cm-2. This could be attributed to the dye's natural optimal light absorption in the visible and NIR region and uniform dispersion through the electrostatic interaction of the cationic derivatives on the TiO2 photoanode. Furthermore, the atomic force microscopy studies and electrochemical investigations using cyclic voltammetry, electrochemical impedance spectroscopy and Bode's plot also supported the enhancement in performance attained with 2AETPPh-Bhcl dye.

6.
Arch Microbiol ; 205(2): 77, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36720740

RESUMEN

In the present work, Amycolatopsis sp. SND-1 (SND-1) was isolated from Cleome chellidonii Linn. (C. chellidonii) was performed as biocontrol and resistance elicitor in Vigna radiata (L.) R. Wilczek (mung bean) plants against Cercospora leaf spot causing pathogen Cercospora canescens (C. canescens). The SND-1 isolate showed 74% of inhibition against C. canescens in dual culture and GC-MS analysis revealed the presence of antifungal compounds. Molecular characterization through 16S rRNA showed that the isolated SND-1 belongs to Amycolatopsis sp. The in vitro plant growth trials exhibited production of indole acetic acid, gibberellic acid, cytokinin, ammonia, hydrogen cyanide, and siderophore and phosphate solubilization. In vivo study with talcum formulation of SND-1 revealed a significant increase in plant root length, shoots length, root and shoot fresh weight, and reduced the disease severity in treated mung bean plants. Triggering of resistance by SND-1 formulation was studied by histochemical depositions and biochemical defense enzymes that resulted in the acceleration in defense response in comparison with control plants. The bioactive endophytic Amycolatopsis sp. SND-1 enhanced the defense against C. canescens infection; hence, it can be used as a biological control agent in mung bean cultivars.


Asunto(s)
Vigna , Amycolatopsis , Endófitos , Cercospora , ARN Ribosómico 16S
7.
Environ Res ; 231(Pt 3): 116212, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37244496

RESUMEN

Anthracnose is a devastating disease caused by the fungus Colletotrichum lindemuthianum (CL) in Vigna radiata (L.) R. Wilczek (mung bean). In the present study, an eco-friendly approach to control anthracnose infection, growth promotion and enhancement of defense response in mung bean plants using endophytic actinomycetes was performed. Among the 24 actinomycetes isolates from the Cleome rutidosperma plant, the isolate SND-2 exhibited a broad spectrum of antagonistic activity with 63.27% of inhibition against CL in the dual culture method. Further, the isolate SND-2 was identified as Streptomyces sp. strain SND-2 (SND-2) through the 16S rRNA gene sequence. In-vitro screening of plant growth trials confirmed that SND-2 has the potential to produce indole acetic acid, hydrogen cyanide, ammonia, phosphate solubilization, and siderophore. The in-vivo biocontrol study was performed with exogenous application of wettable talcum-based formulation of SND-2 strain to mitigate CL infection in mung bean seedlings. The results displayed maximum seed germination, vigor index, increased growth parameters, and lowest disease severity (43.63 ± 0.73) in formulation treated and pathogen challenged mung bean plants. Further, the application of SND-2 formulation with pathogen witnessed increased cellular defense through the maximum accumulation of lignin, hydrogen peroxide and phenol deposition in mung bean leaves compared with control treatments. Biochemical defense response exhibited upregulation of antioxidant enzymes such as phenylalanine ammonia-lyase, ß-1,-3-Glucanase, and peroxidase enzymes activities with increased phenolic (3.64 ± 0.11 mg/g fresh weight) and flavonoid (1.14 ± 0.05 mg/g fresh weight) contents in comparison with other treatments at 0, 4, 12, 24, 36, and 72 h post pathogen inoculation. This study demonstrated that formulation of Streptomyces sp. strain SND-2 is a potential source as a suppressive agent and plant growth promoter in mung bean plants upon C. lindemuthianum infestation and witnesses the elevation in cellular and biochemical defense against anthracnose disease.


Asunto(s)
Fabaceae , Streptomyces , Vigna , Vigna/química , Vigna/genética , Streptomyces/genética , ARN Ribosómico 16S/genética , Fabaceae/genética , Antioxidantes
8.
Environ Res ; 229: 116008, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37121347

RESUMEN

Nowadays, the increased number of multidrug-resistant strains among pathogens is a severe public health concern and cancer is posing a great threat for humans. These problems should be tackled with the development of novel and broad-spectrum antimicrobials from microbial origin. During the present study, the bioactive secondary metabolites from Aspergillus niger CJ6 were extracted, characterized; their biological properties were evaluated by subjecting them for antimicrobial, antifungal and anticancer activities. The potent isolate Aspergillus niger CJ6 with nucleotide sequence of 959 base pairs showed antagonistic activity against fungal pathogens in dual culture. The chemical profiling of crude ethyl acetate extract indicated the presence of various bioactive molecules belonging to phenolic, hydrocarbons, and phthalate derivative classes. In antimicrobial activity, the crude extract displayed increasing activity with increased concentration; the highest activity observed against Shigella flexneri with 15 ± 1.0, 19 ± 0.5, 20 ± 1.0 and 24 ± 1.0 mm zones of inhibition at 25, 50, 75 and 100 µl concentrations. The MTT assay illustrated deformed cells of MIA PaCa-2 cell line in in-vitro cytotoxic activity; outflow of cell matrix and membrane rupture; the IC50 of 90.78 µg/ml suggested moderate potential of extract to prevent cancer cell growth. The apoptosis/necrosis study by flow cytometer exhibited 8.98 ± 0.85% early and 73 ± 0.7% of late apoptotic population with 3.8 ± 1.1% necrotic cells; only 14.22 ± 0.6% of healthy cells suggested the increased apoptosis inducing capacity of Aspergillus niger CJ6 crude extract. The outcomes of this study persuade further exploration on the identification, purification and development of novel bioactive agents that could help battle fatal diseases in humans.


Asunto(s)
Antiinfecciosos , Aspergillus niger , Humanos , Extractos Vegetales/farmacología , Antiinfecciosos/farmacología , Línea Celular , Apoptosis
9.
Environ Res ; 225: 115614, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36889569

RESUMEN

Biosynthesized silver nanoparticles (AgNPs) are gaining popularity due to their distinctive biological applications. In this research work, an eco-friendly method of synthesizing AgNPs from the leaf polysaccharide (PS) of Acalypha indica L. ( A. indica) was carried out. Synthesis of polysaccharide-AgNPs (PS-AgNPs) was indicated by visual detection of colour change from pale yellow to light brown. The PS-AgNPs were characterized with different techniques and further evaluated for biological activities. The Ultra violet-visible (UV-Vis.) spectroscopy expressed a sharp absorption peak at 415 nm confirmed the synthesis. Atomic force microscopy (AFM) analysis revealed the size range of particles from 14 nm to 85 nm. Fourier transform infrared (FTIR) analysis detected the presence of various functional groups. The cubic crystalline structure of PS-AgNPs was confirmed by X-ray diffraction (XRD) and the particles were found to be oval to polymorphic shaped through transmission electron microscopy (TEM) with sizes from 7.25 nm to 92.51 nm. Energy dispersive X-ray (EDX) determined the presence of silver in PS-AgNPs. The zeta potential was -28.0 mV, which confirmed the stability and an average particle size of 62.2 nm was calculated through dynamic light scattering (DLS). Lastly, the thermo gravimetric analysis (TGA) showed the PS-AgNPs were resistant to high temperature. The PS-AgNPs exhibited significant free radical scavenging activity with an IC50 value of 112.91 µg/ml. They were highly capable of inhibiting the growth of different bacterial and plant fungal pathogens and also active to reduce the cell viability of prostate cancer (PC-3) cell line. The IC50 value was 101.43 µg/ml. The flow cytometric apoptosis analysis revealed the percentage of viable, apoptotic and necrotic cells of PC-3 cell line. According to this evaluation, it can be concluded that these biosynthesized and environmentally friendly PS-AgNPs are helpful to improve therapeutics because of significant antibacterial, antifungal, antioxidant, and cytotoxic properties to open up new possibilities for euthenics.


Asunto(s)
Acalypha , Nanopartículas del Metal , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/química , Plata/farmacología , Plata/química , Antioxidantes/farmacología , Bacterias/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Antibacterianos/farmacología
10.
Arch Microbiol ; 204(9): 540, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35927484

RESUMEN

During the investigation, soil actinomycetes were isolated from Kathlekanu swamp forest and the crude ethyl acetate extract from the potent isolate KF15 was analysed with GC-MS and HPTLC to identify bioactive metabolites. The crude extract was examined for in-vitro antifungal activity on pathogens of chilli; MTT cytotoxicity assay was performed against HeLa cell line to determine the anticancer potential. The isolate Streptomyces sp. strain KF15 exhibited antagonistic activity against fungal pathogens by inhibiting growth and altering growth pattern with increased antimicrobial activity in dose-dependent manner. GC-MS revealed many bioactive compounds and HPTLC depicted metabolite fingerprint. The IC50 of 99.85 µg/ml indicated the high potential of KF15 extract to prevent proliferation of HeLa cells. Therefore, the findings of this study indicate that the crude extract from Streptomyces sp. strain KF15 contains antifungal and anticancer metabolites; further study on purification could help in controlling many fungal diseases as well as cervical cancer in humans.


Asunto(s)
Streptomyces , Antifúngicos , Mezclas Complejas/metabolismo , Bosques , Células HeLa , Humanos , Humedales
11.
J Org Chem ; 87(14): 8956-8969, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35765119

RESUMEN

A highly efficient microwave-assisted copper(II)-catalyzed cyclization cascade was established starting from readily accessible O/N-propargylated 2-hydroxy or 2-aminobenzaldehydes and o-phenylenediamines to synthesize densely functionalized imidazo[1,2-d][1,4]oxazepines and imidazo[1,2-d][1,4]diazepines in high yields (up to 93%). This one-pot two-step process was found to be highly atom economical (-H2O, -H2) and operationally simple and enabled the generation of two new heterocycle rings (seven- and five-membered) and three new C-N bonds in a single synthetic operation. These reactions well tolerated a variety of substituents including electron-donating and electron-withdrawing groups and furnished the desired fused heterocycles in high yields under microwave irradiation in a very short reaction time. The mechanism of the established protocol involves sequential imine formation-intramolecular cyclization-air oxidation followed by 7-exo-dig cyclization steps. A comparative study between the microwave-assisted approach and conventional heating was also performed to demonstrate the advantages of the microwave-assisted protocol in terms of high yield and shorter reaction time.


Asunto(s)
Cobre , Oxazepinas , Azepinas , Catálisis , Ciclización , Microondas , Fenilendiaminas
12.
Environ Res ; 214(Pt 1): 113743, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35772503

RESUMEN

The RGO-supported HoVO4-ZnO nanocomposite was synthesized using the ultra sonication process. X-ray diffraction patterns, Field emission scanning electron microscopy, high resolution transmission electron microscopy, Diffractive Reflectance spectroscopy, and photoluminescence spectroscopy were employed to examine the heterostructured photocatalyst in this research study. The photocatalytic efficiency of the RGO-supported HoVO4-ZnO nanoparticles, under UV light irradiation, in the degradation of Rhodamine-B dye was investigated. Undoped ZnO, bare HoVO4, and HoVO4 -ZnO, degraded at 55.6, 57.5, and 74.33 percent in 45 min, respectively. This new RGO coupled HoVO4-ZnO exhibits enhanced photocatalytic efficiency compared to the bare ZnO and HoVO4-ZnO nanocomposite.


Asunto(s)
Óxido de Zinc , Catálisis , Grafito , Rodaminas , Ultrasonido
13.
Bioorg Chem ; 110: 104798, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33735710

RESUMEN

Novel spirooxindolopyrrolidine embedded indandione heterocyclic hybrids were obtained in excellent yields via a regio- and stereoselective one-pot three component reaction between Baylis-Hillman adduct and non-stabilized azomethine ylides. The structure of newly synthesized compounds was elucidated through 1D and 2D spectroscopic data and the stereochemistry was determined by single crystal X-ray diffraction analysis. In vitro tubercular activity against Mycobacterium tuberculosis H37Rv using MABA assay reveals that the compound bearing chlorine substituted on the oxindole ring displayed the most potent activity with MIC 0.78 µg/mL and is two-fold active than the standard drug, ethambutol (MIC 1.56 µg/mL).


Asunto(s)
Antibacterianos/farmacología , Indanos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Oxindoles/farmacología , Pirrolidinas/farmacología , Compuestos de Espiro/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Indanos/síntesis química , Indanos/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oxindoles/síntesis química , Oxindoles/química , Pirrolidinas/síntesis química , Pirrolidinas/química , Compuestos de Espiro/síntesis química , Compuestos de Espiro/química , Estereoisomerismo , Relación Estructura-Actividad
14.
Mikrochim Acta ; 188(12): 414, 2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34751825

RESUMEN

Graphene oxide-rhodamine B hydrazide (GO-RhB) nanocomposite was prepared by a simple chemical method and characterized by various spectroscopic and analytical techniques. GO-RhB nanocomposite potentially detects Cr3+ ion (excitation/emission = 550 nm/572 nm) via fluorescence turn "on-off" approach. This composite showed high binding affinity (106 M-1) with Cr3+ and a+ limit of detection (LOD) down to picomolar concentration (LOD = 85.6 pM). As far as we know, this is the first report for the sensing of Cr3+ ion at picomolar concentration. GO-RhB selectively senses Cr3+ ion without any interference of other coexisting metal ions. In addition, this composite exhibited the dynamic nature of quenching in the presence of Cr3+ ion, which is confirmed by the Stern-Volmer plot, fluorescence temperature profiles, and decay time experiments. The GO-RhB nanocomposite-based fluorescent probe was successfully applied to the quantitative detection of Cr3+ ion in milk sample (linear range = 2 to 10 nM) with better performance than other existing methods. Besides, this GO-RhB composite showed better antibiofilm activity against Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus (MRSA) by using the Congo red agar and tube method.


Asunto(s)
Biopelículas/efectos de los fármacos , Cromo/química , Fluorometría/métodos , Grafito/química , Nanocompuestos/química , Rodaminas/química , Acinetobacter baumannii/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Contaminantes Ambientales/química , Fluorescencia , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos
15.
Molecules ; 27(1)2021 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-35011374

RESUMEN

Quinoline Schiff bases display potential applications in optoelectronics and laser fields because of their unique optical properties that arise from extensive delocalization of the electron cloud, and a high order of non-linearity. In this context, a new class of conjugated quinoline-derivative viz. N-(quinolin-3-ylmethylene)anilines were synthesized from 2-hydroxyquinoline-3-carbaldehyde in two good yielding steps. The ability of these imines to accept an electron from a donor is denoted by their electron acceptor number and sites, which is calculated using density functional theory (DFT). The optical properties such as FT-IR, Raman, UV-VIS, and EDS spectra were calculated using TD-DFT, which also provided the energy gap, HOMO-LUMO structure. The optical properties of the synthesized imino quinolines were experimentally studied using photoluminescence and absorption spectroscopy. The properties such as Stokes shift and quantum yield were calculated using experimental data. Furthermore, the compound bearing a methyl group on the aryl ring and ZnO nanoparticles (hydrothermally synthesized) were dissolved in toluene, and optically excited with a 355 nm nanosecond laser, which produced a random laser.

16.
Bioorg Med Chem Lett ; 30(2): 126789, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31753696

RESUMEN

A small library of structurally fascinating spiropyrrolidine tethered imidazole heterocylic hybrids has been synthesized regioselectively in good yields employing [bmim]Br mediated 1,3-diplar cycloaddition strategy. The new class of azomethine ylide generated in situ from l-histidine and 11H-indeno[1,2-b]quinoxalin-11-one reacts with various substituted ß-nitrostyrenes affording the spiropyrrolidine tethered imidazole heterocylic hybrids. Compounds thus synthesized were assessed for their in vitro cholinesterase (ChEs) inhibitory activities, among them compounds possessing 4-methyl and 4-methoxy substituents on the aryl ring showed potent activities with IC50 values of 2.02 ±â€¯0.05 and 2.05 ±â€¯0.06 µM against AChE and 12.40 ±â€¯0.14 and 11.45 ±â€¯0.28 µM against BChE enzyme, respectively. In addition, the most active compounds were performed for their molecular docking simulation and the results revealed interesting binding templates to the active site channel of cholinesterase enzymes.


Asunto(s)
Acetilcolinesterasa/metabolismo , Butirilcolinesterasa/metabolismo , Diseño de Fármacos , Imidazoles/química , Pirrolidinas/química , Compuestos de Espiro/química , Acetilcolinesterasa/química , Sitios de Unión , Butirilcolinesterasa/química , Dominio Catalítico , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/metabolismo , Reacción de Cicloadición , Humanos , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad
17.
Molecules ; 25(20)2020 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-33080968

RESUMEN

Our synthetic approach for the assembly of structurally complex spirooxindole heterocyclic hybrids was based on an ionic liquid, [bmim]Br mediated one-pot three-component cascade reaction strategy involving 1,3-dipolar cycloaddition reaction of N-1-(2-pyridinylmethyl)-3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones and azomethine ylide generated in situ from isatin and L-phenyl alanine, affording a series of spirooxindole-pyrrolidine heterocyclic hybrids in good-to-excellent yields. In addition to serving as the reaction medium, [bmim]Br also functioned as a catalyst in this cycloaddition reaction and hence accelerated the reaction rate affording the cycloadducts in short reaction time.


Asunto(s)
Compuestos Heterocíclicos/química , Líquidos Iónicos/química , Isatina/química , Piridonas/química , Compuestos de Espiro/química , Compuestos Azo/química , Reacción de Cicloadición , Compuestos Heterocíclicos/síntesis química , Indoles/química , Estructura Molecular , Oxindoles/química , Pirrolidinas/química , Tiosemicarbazonas/química
18.
Molecules ; 25(23)2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33261115

RESUMEN

With an aim to develop more effective and affordable anticancer agents possessing a unique mechanism of action, we designed and synthesized derivatives of spirooxindole-pyrrolidine heterocyclic hybrids in good yields through a one-pot three-component (3+2) cycloaddition strategy. The synthesized compounds were characterized thoroughly for the physicochemical properties by making use of FT-IR, NMR spectroscopy, and mass spectrometry. Further, these compounds have been evaluated for the influence of anticancer activity against HepG2 cells up to 200 µg/mL concentration. The highly active molecular scaffold was tested for the in-depth mechanistic studies, and it was found that the major pathway of cell death is apoptosis which occurs through the induction of reactive oxygen species followed by the involvement of caspases.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Compuestos Heterocíclicos/química , Pirrolidinas/química , Compuestos de Espiro/química , Apoptosis , Proliferación Celular , Reacción de Cicloadición , Células Hep G2 , Humanos , Técnicas In Vitro , Estructura Molecular , Relación Estructura-Actividad
19.
Bioorg Med Chem ; 27(12): 2487-2498, 2019 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-30853330

RESUMEN

A small library of spirooxindole-pyrrolidine hybrids have been synthesized for the first time in an ionic liquid, [bmim]Br in good to excellent yields employing a new class of non-stabilized azomethine ylides derived from isatin and tyrosine, a combination that has been rarely employed for the in situ generation of azomethine ylides using [3+2] cycloaddition strategy. Following the synthesis and characterization of the spirooxindole-pyrrolidine heterocyclic hybrids, they were tested for their anticancer activity as against the changes in the concentrations and time periods with different in vitro cell cultures containing cancer and non-cancer cells, where the results revealed for a potential therapeutic activity. Further analysis for the mechanism of cell death by the cancer cells indicated for the caspase-dependent apoptotic pathway, specifically mediated by caspase-3. Based on these results, it can be demonstrated that the synthesized spirooxindole-pyrrolidine hybrids may serve as one of the better therapeutic agents used for the treatment of malignant tumors.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Indoles/química , Pirrolidinas/química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Reacción de Cicloadición , Humanos , Compuestos de Espiro/química , Relación Estructura-Actividad
20.
Bioorg Med Chem ; 27(12): 2621-2628, 2019 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-30952387

RESUMEN

A small library of new class of dispiropyrrolidinyl-piperidone tethered indono[1,2-b]quinoxaline heterocyclic hybrids 7a-j were synthesized employing multicomponent 1,3-dipolar cycloaddition strategy in [bmim]Br. The azomethine ylide employed is first of its kind and generated in situ from indenoquinoxalinone and l-tryptophan, a combination that has not been employed previously for the in situ generation of azomethine ylides. The synthesized heterocyclic hybrids 7a-j were evaluated for their in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities, therein compounds 7h and 7j displayed more potent AChE and BChE enzyme inhibition than the standard drug with IC50 values of 3.22, 2.01, 12.40 and 10.45 mM, respectively. Molecular docking studies have also been investigated for most active compounds that disclosed interesting binding templates to the active site channel of cholinesterase enzyme.


Asunto(s)
Acetilcolinesterasa/metabolismo , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/síntesis química , Simulación del Acoplamiento Molecular , Piperidonas/química , Quinoxalinas/química , Acetilcolinesterasa/química , Sitios de Unión , Butirilcolinesterasa/química , Dominio Catalítico , Inhibidores de la Colinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacocinética , Semivida , Humanos , Concentración 50 Inhibidora , Solubilidad
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