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141.
Kiran Y. B. Rambabu G. Vijayakumar V. Barbosa L. C. A. 《Russian Journal of Organic Chemistry》2021,57(7):1158-1166
Russian Journal of Organic Chemistry - A green acetic acid-mediated synthesis of kojic acid derivatives through a multicomponent reaction (MCR) has been developed. This new protocol is simple and... 相似文献
142.
Gomes Antonio Taylon Aguiar Pereira Rayanne Rocha Duarte Junior Anivaldo Pereira da Cruz Rodrigues Antonio Manoel Remédios Claudio Marcio Rocha Brasil Davi do Socorro Barros Morais Luiz Roberto Barbosa Silva-Júnior José Otávio Carréra Ribeiro-Costa Roseane Maria 《Journal of Thermal Analysis and Calorimetry》2022,147(1):355-365
Journal of Thermal Analysis and Calorimetry - Native Amazon palm trees have been target of research and product development especially because of their oil and fat. Tucumã-do-Pará... 相似文献
143.
Luis Fernando B. Duarte Eduardo S. Barbosa Renata L. Oliveira Mikaela P. Pinz Benhur Godoi Ricardo F. Schumacher Cristiane Luchese Ethel A. Wilhelm Diego Alves 《Tetrahedron letters》2017,58(33):3319-3322
We described here an alternative method for the synthesis of 4-arylselanyl-7-chloroquinolines through reactions of 4,7-dichloroquinoline with organylselenols, generated in situ by the reaction of diorganyl diselenides with H3PO2 (50 wt% in H2O). These reactions proceeded efficiently at 60 °C under N2 atmosphere and are suitable to a range of diorganyl diselenides containing electron-donating and electron-withdrawing groups, affording the corresponding 4-aryl-7-chloroquinolines in high yields. The synthesized compounds were screened for their in vitro acetylcholinesterase (AChE) activity and our results demonstrated that the 7-chloro-4-[(4-fluorophenyl)selanyl]quinoline inhibited the AChE activity and improved memory in mice, making this compound is a potential therapeutic agent for the treatment of Alzheimer disease and other neurodegenerative disorders. 相似文献
144.
E. M. Araújo Renata Barbosa Crislene R. S. Morais L. E. B. Soledade A. G. Souza Moema Q. Vieira 《Journal of Thermal Analysis and Calorimetry》2007,90(3):841-848
Nanocomposites containing both polyethylene and montmorillonite clay organically modified with four different types of quaternary
ammonium salts were obtained via direct melt intercalation. Thus, the main purpose of this work was to evaluate the effect
of the organoclay on the thermal stability of polyethylene. The organoclays were characterized by XRD, FTIR, DSC and TG. The
polyethylene/organoclay nanocomposites were studied by XRD, TEM, TG, besides an evaluation of their mechanical properties.
The results showed that the salts were incorporated by intercalation between the layers of the organoclay and, apparently
that the nanocomposites were more thermally stable than pure polyethylene. 相似文献
145.
Barbosa S Cheema MA Taboada P Mosquera V 《The journal of physical chemistry. B》2007,111(37):10920-10928
The micellar properties and solubilization capacity of poorly water soluble drugs of several micellar and gel solutions of diblock and triblock copolymers of styrene oxide/ethylene oxide have been measured and compared with block copolymers of butylene oxide/ethylene oxide, showing that the solubilization capacity of the styrene oxide block is approximately four times that of a butylenes oxide block for dilute solutions. To continue establishing the correlation between micellar characteristics and solubilization capacity, we have found it interesting to compare the micellar and gelation properties of the diblock and triblock copolymers PSO10PEO135 and PEO69PSO8PEO69 (subindexes are the number-average block lengths), with different architecture but similar average block lengths. Surface tension measurements allowed the determination of the critical micelle concentrations at several temperatures and, so, to calculate standard enthalpies of micellization. Static and dynamic light scattering data permitted us to determine micellar parameters and to obtain qualitatively the extent of hydration of the copolymer micelle. A tube inversion method was used to define the mobile-immobile (soft-hard gel) phase boundary. To refine the phase diagram and observe the existence of additional phases, rheological measurements were done. The results are in good agreement with previous values published for PSOnPEOm and PEOmPSOnPEOm copolymers. 相似文献
146.
147.
Priscilla Augusta de Sousa Fernandes Raimundo Luiz Silva Pereira Antonia Thassya Lucas dos Santos Henrique Douglas Melo Coutinho Maria Flaviana Bezerra Morais-Braga Viviane Bezerra da Silva Adrielle Rodrigues Costa Maria Elizete Machado Generino Maraiza Gregorio de Oliveira Saulo Almeida de Menezes Luciano Temoteo dos Santos Abolghasem Siyadatpanah Polrat Wilairatana Tain Machado Aguiar Portela Ma Aparecida Barbosa Ferreira Gonalo Jos Weverton Almeida-Bezerra 《Molecules (Basel, Switzerland)》2022,27(10)
One of the main global problems that affect human health is the development of bacterial resistance to different drugs. As a result, the growing number of multidrug-resistant pathogens has contributed to an increase in resistant infections and represents a public health problem. The present work seeks to investigate the chemical composition and antibacterial activity of the essential oil of Syzygium cumini leaves. To identify its chemical composition, gas chromatography coupled to mass spectrometry was used. The antibacterial activity test was performed with the standard strains Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 25853 and Staphylococcus aureus ATCC 25923 and multidrug-resistant clinical isolates E. coli 06, P. aeruginosa 24 and S. aureus 10. The minimum inhibitory concentration (MIC) was determined by serial microdilution as well as the verification of the modulating effect of the antibiotic effect. In this test, the oil was used in a subinhibitory concentration. The test reading was performed after 24 h of incubation at 37 °C. The results show that the major chemical constituent is α-pinene (53.21%). The oil showed moderate activity against E. coli ATCC 25922, with the MIC of 512 µg/mL; there was no activity against the other strains. The oil potentiated the effect of antibiotics demonstrating possible synergism when associated with gentamicin, erythromycin and norfloxacin against E. coli 06 and S. aureus 10. 相似文献
148.
Estitxu Echenique-Errandonea Sara Rojas Víctor Karim Abdelkader-Fernndez Manuel Prez-Mendoza Ricardo F. Mendes Paula Barbosa Filipe Figueiredo Flvio Figueira Filipe A. Almeida Paz Jos Manuel Delgado-Lpez Antonio Rodríguez-Diguez Jos Manuel Seco 《Molecules (Basel, Switzerland)》2022,27(22)
Due to the fast, emerging development of antibiotic-resistant bacteria, the need for novel, efficient routes to battle these pathogens is crucial; in this scenario, metal-organic frameworks (MOFs) are promising materials for combating them effectively. Herein, a novel Cu-MOF—namely 1—that displays the formula [Cu3L2(DMF)2]n (DMF = N,N-dimethylformamide) is described, synthesized by the combination of copper(II) and 3,4-dihydroxybenzoic acid (H3L)—both having well-known antibacterial properties. The resulting three-dimensional structure motivated us to study the antibacterial activity, adsorptive capacity and processability of the MOF in the form of pellets and membranes as a proof-of-concept to evaluate its future application in devices. 相似文献
149.
Oberdan Oliveira Ferreira Jorddy Neves Cruz ngelo Antnio Barbosa de Moraes Celeste de Jesus Pereira Franco Rafael Rodrigues Lima Taina Oliveira dos Anjos Giovanna Moraes Siqueira Lidiane Diniz do Nascimento Mrcia Moraes Cascaes Mozaniel Santana de Oliveira Eloisa Helena de Aguiar Andrade 《Molecules (Basel, Switzerland)》2022,27(14)
Essential oils are biosynthesized in the secondary metabolism of plants, and in their chemical composition, they can be identified different classes of compounds with potential antioxidant and biological applications. Over the years in the Amazon, several species of aromatic plants were discovered and used in traditional medicine. The literature has shown that essential oils extracted from amazon species have several biological activities, such as antioxidant, antibacterial, antifungal, cytotoxic, and antiprotozoal activities. These activities are related to the diversified chemical composition found in essential oils that, by synergism, favors its pharmacological action. In light of this vital importance, this study aimed at performing a review of the literature with particular emphasis on the chemical composition and biological activities in studies conducted with species collected in the Amazon, taking into consideration in particular the last 10 years of collection and research. 相似文献
150.
Metabolic profiling for the identification of Huntington biomarkers by on‐line solid‐phase extraction capillary electrophoresis mass spectrometry combined with advanced data analysis tools 下载免费PDF全文
Laura Pont Fernando Benavente Joaquim Jaumot Romà Tauler Jordi Alberch Silvia Ginés José Barbosa Victoria Sanz‐Nebot 《Electrophoresis》2016,37(5-6):795-808
In this work, an untargeted metabolomic approach based on sensitive analysis by on‐line solid‐phase extraction capillary electrophoresis mass spectrometry (SPE‐CE‐MS) in combination with multivariate data analysis is proposed as an efficient method for the identification of biomarkers of Huntington's disease (HD) progression in plasma. For this purpose, plasma samples from wild‐type (wt) and HD (R6/1) mice of different ages (8, 12, and 30 weeks), were analyzed by C18‐SPE‐CE‐MS in order to obtain the characteristic electrophoretic profiles of low molecular mass compounds. Then, multivariate curve resolution alternating least squares (MCR‐ALS) was applied to the multiple full scan MS datasets. This strategy permitted the resolution of a large number of metabolites being characterized by their electrophoretic peaks and their corresponding mass spectra. A total number of 29 compounds were relevant to discriminate between wt and HD plasma samples, as well as to follow‐up the HD progression. The intracellular signaling was found to be the most affected metabolic pathway in HD mice after 12 weeks of birth, when mice already showed motor coordination deficiencies and cognitive decline. This fact agreed with the atrophy and dysfunction of specific neurons, loss of several types of receptors, and changed expression of neurotransmitters. 相似文献