99 research outputs found

    Estudios de acoplamiento molecular de nuevos análogos de quinolonas a la ADN girasa de Escherichia coli

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    Indexación: Scopus.Chemicals and CAS Registry Numbers: amino acid, 65072-01-7; ciprofloxacin, 85721-33-1; DNA topoisomerase (ATP hydrolysing); gatifloxacin, 112811-59-3, 180200-66-2; levofloxacin, 100986-85-4, 138199-71-0; lomefloxacin, 98079-51-7; moxifloxacin, 151096-09-2; nalidixic acid, 389-08-2; oxolinic acid, 14698-29-4; pipemidic acid, 51940-44-4; rufloxacin, 101363-10-4; sitafloxacin, 127254-12-0, 163253-35-8Context: Bacterial resistance to antibiotics is the inevitable consequence of the use of antimicrobial agents. Thus, quinolones are an important class of antibacterials; these agents generally consist of a 1-subtituted-1,4-dihydro-4-oxopyridine-3-carboxylic acid moiety combined with an aromatic or heteroaromatic ring fused at the 5- and 6-position. Aims: To determine the binding of quinolones to DNA gyrase of Escherichia coli. Methods: An analysis was performed using an in silico approach to determine, by docking calculations and energy descriptors, the conformer of 4‐oxo‐1,4‐dihydroquinoline skeleton that forms the most stable complex with DNA gyrase of E. coli. Results: The complex shows that the pose of the quinolones coincides with the amino acid residues Asp87, Thr88, Arg91 and Met92, which is expected to be critical in the binding of quinolones to DNA gyrase of E. coli. A series of quinolones were computationally designed, and the interactions between the quinolones and the amino acid residues of the DNA gyrase were calculated. Conclusions: Among the designed compounds, compounds 105 and 115 exhibit higher binding energy values and interact with amino acids Asp87, Thr88, Arg91 and Met92. © 2018 Journal of Pharmacy & Pharmacognosy Research.http://jppres.com/jppres/pdf/vol6/jppres18.368_6.5.386.pd

    NEW PHOSPHORUS COMPOUNDS K[PCL3(X)] (X= SCN, CN): PREPARATION AND DFT AND SPECTROSCOPIC STUDIES

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    Indexación: Web of Science. Scielo.Two new phosphorus complexes, potassium trichlorothiocyanophosphate (III) (PTCTCP; K[PCl3(SCN)]) and potassium trichlorocyanophosphate (III) (PTCCP; K[PCl3(CN)]) were synthesized from the reaction of KSCN and KCN, respectively, with PC^. The chemical formulas and compositions of these compounds were determined by elemental analysis and spectroscopic methods, such as phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy (31P-NMR), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy and mass spectrophotometry. All of the theoretical calculations and determinations of the properties of these compounds were performed as part of the Amsterdam Density Functional (ADF) program. Excitation energies were assessed using time-dependent perturbation density functional theory (TD-DFT). In addition, the molecular geometry was optimized and the frequencies and excitation energies were calculated using standard Slater-type orbital (STO) basis sets with triple-zeta quality double plus polarization functions (TZ2P) for all of the atoms. The assignment of the principal transitions and total densities of state (TDOS) for orbital analysis were performed using the GaussSum 2.2 program.http://www.scielo.cl/pdf/jcchems/v61n1/art15.pd

    A Multiwavelength View of a Mass Outflow from the Galactic Center

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    The Galactic center (GC) lobe is a degree-tall shell of gas that spans the central degree of our Galaxy. It has been cited as evidence for a mass outflow from our GC region, which has inspired diverse models for its origin. However, most work has focused on the morphology of the GC lobe, which has made it difficult to draw strong conclusions about its nature. Here, I present a coherent, multiwavelength analysis of new and archival observations of the GC lobe. Radio continuum emission shows that the GC lobe has a magnetized layer with a diameter of 110 pc and an equipartition field strength ranging from 40 to 100 μ\muG. Recombination line emission traces an ionized shell nested within the radio continuum with diameter of 80 pc and height 165 pc. Mid-infrared maps at 8 and 15 μ\mum show that the GC lobe has a third layer of warm dust and PAH-emission that surrounds the radio continuum shell with a diameter of 130 pc. Assuming adiabatic expansion of the gas in the GC lobe, its formation required an energy input of about 5×10525\times10^{52} ergs. I compare the physical conditions of the GC lobe to several models and find best agreement with the canonical starburst outflow model. The formation of the GC lobe is consistent with the currently observed pressure and star formation rate in the central tens of parsecs of our Galaxy. Outflows of this scale are more typical of dwarf galaxies and would not be easily detected in nearby spiral galaxies. Thus, the existence of such an outflow in our own Galaxy may indicate that it is relatively common phenomenon in the nuclei of spiral galaxies. (Abridged)Comment: Accepted to ApJ. 15 pages, 8 (compressed) figure

    Madia sativa (Asteraceae), una planta araucana

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    Madia sativa remains important to the traditional culture of many first peoples of Chile and is being studied for its biological abilities by medical researchers. The used of this specie in Chile is researched through a series of retrospective analysis. This research indicated the use this plant populations mapuche a long time ago.Madia sativa sigue siendo importante para la cultura tradicional de muchos pueblos originarios de Chile y está siendo estudiada por sus capacidades biológicas por investigadores médicas. El uso de esta especie en Chile se investiga a través de una serie de análisis retrospectivos. Esta investigación indica el uso de esta planta en poblaciones mapuche desde hace mucho tiempo

    Docking studies on novel analogs of quinolones against DNA gyrase of Escherichia coli

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    Context: Bacterial resistance to antibiotics is the inevitable consequence of the use of antimicrobial agents. Thus, quinolones are an important class of antibacterials; these agents generally consist of a 1-subtituted-1,4-dihydro-4-oxopyridine-3-carboxylic acid moiety combined with an aromatic or heteroaromatic ring fused at the 5- and 6-position. Aims: To determine the binding of quinolones to DNA gyrase of Escherichia coli. Methods: An analysis was performed using an in silico approach to determine, by docking calculations and energy descriptors, the conformer of 4‐oxo‐1,4‐dihydroquinoline skeleton that forms the most stable complex with DNA gyrase of E. coli. Results: The complex shows that the pose of the quinolones coincides with the amino acid residues Asp87, Thr88, Arg91 and Met92, which is expected to be critical in the binding of quinolones to DNA gyrase of E. coli. A series of quinolones were computationally designed, and the interactions between the quinolones and the amino acid residues of the DNA gyrase were calculated. Conclusions: Among the designed compounds, compounds 105 and 115 exhibit higher binding energy values and interact with amino acids Asp87, Thr88, Arg91 and Met92

    Perspectiva teòrica sobre les activitats estructurals i els objectius dels glucòsids de Kaempferol

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    Metabolite profile always hold important place for flavonoids as they are the major promoters of secondary metabolism in human body. For decades numerous flavonoids are explored for their structural activities which in turn helped them to meet various health promoting applications such as radical scavenging activity. Apart from conventional flavonoids their derivatives are also tend to exhibit similar kind of structural activity. Therefore, in the present work afzelin and juglanin – the glycosyl derivatives of kaemepferol an established flavonoid are subjected to structural activity relationship analysis using density functional theory. The structures of the two kaempferol glycosides are optimized and the optimized geometry is simulated to obtain frontier orbitals, electrostatic potential energy and molecular descriptors. The obtained results suggest that maximum amount of charge is accumulated over B-ring of two flavonoids, thus prefers to act as better electron donating region. Target predicted for two flavonoids over homosapien class reveal that the flavonoid highly prefers lyase and enzymatic targets for inhibition purpose

    Relationships between the structural characteristic of curcumins that affect cell proliferation of hepatocarcinoma cells

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    Relationships between the structural characteristic of curcumin and dimethoxycurcumin and their antitumoral activity were studied. Treatment of HepG2 cells for 24 h with the curcumin and dimethoxycurcumin resulted in apoptosis induction and dose-dependent inhibition of cell proliferation. The calculated docking and the DFT method, suggest a structure-activity relationship between the activities of dimethoxycurcumin and curcumin structure and the apoptosis in HepG2 cell

    Academic intervention in northern Guanajuato. A university proposal contribution to local development

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    Este trabajo aborda una experiencia de intervención académica desde una universidad pública a una región considerada de bajo desarrollo humano: el norte de Guanajuato. Se partió de una evaluación diagnóstica de la situación de vulnerabilidad económica, social y política, y se extendió a un marco de recomendaciones de políticas públicas que pretenden incidir en los llamados ‘tres vértices del desarrollo local’: calidad del gobierno local, desarrollo social y desarrollo económico. Todo ello como una forma de colaborar en la construcción de posibilidades de cambio y superación de la mano de la población y gobierno localThis paper deals with an experience of academic intervention from a public university to a region considered low human development: northern Guanajuato. It began with a diagnostic assessment of situation of economic, social and political vulnerability, and spread to a framework of policy policies recommendations intended to influence the so-called ‘three vertices of local development’: quality of local government, social development and economic development. All as a way to collaborate in the construction of possibilities for change and improvement of labor population and local government

    Synthesis, chemical identification, drug release and docking studies of the Amlodipine–Chitosan nanobiopolymer composite

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    A new amlodipine-chitosan nanocomposite was built using amlodipine nanoparticles as primary scaffolds by spontaneous emulsification, and its complete elucidation was performed by using several spectrometric techniques. Our results indicate that the amlodipine-chitosan nanocomposite has better solubility than amlodipine at pH 7.4 with a nearly all the drug substance dissolved (97%) by the final time-point measured. The docking study support the existence of intermolecular interactions are established between amlodipine and chitosa

    Octahedral molybdenum cluster complexes with aromatic sulfonate ligands

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    This article describes the synthesis, structures and systematic study of the spectroscopic and redox properties of a series of octahedral molybdenum metal cluster complexes with aromatic sulfonate ligands (nBu4N)2[{Mo6X8}(OTs)6] and (nBu4N)2[{Mo6X8}(PhSO3)6] (where X- is Cl-, Br- or I-; OTs- is p-toluenesulfonate and PhSO3 - is benzenesulfonate). All the complexes demonstrated photoluminescence in the red region and an ability to generate singlet oxygen. Notably, the highest quantum yields (>0.6) and narrowest emission bands were found for complexes with a {Mo6I8}4+ cluster core. Moreover, cyclic voltammetric studies revealed that (nBu4N)2[{Mo6X8}(OTs)6] and (nBu4N)2[{Mo6X8}(PhSO3)6] confer enhanced stability towards electrochemical oxidation relative to corresponding starting complexes (nBu4N)2[{Mo6X8}X6]
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