948 resultados para hydroxy-sodalite


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T-cell mediated immune response (CMI) hasbeen widely studied in relation to individual andfitness components in birds. However, few studieshave simultaneously examined individual and socialfactors and habitat-mediated variance in theimmunity of chicks and adults from the samepopulation and in the same breeding season. Weinvestigated ecological and physiological variancein CMI of male and female nestlings and adults in abreeding population of Cory's Shearwaters(Calonectrisdiomedea) in theMediterranean Sea. Explanatory variables includedindividual traits (body condition, carbon andnitrogen stable isotope ratios, plasma totalproteins, triglycerides, uric acid, osmolarity,β-hydroxy-butyrate, erythrocyte meancorpuscular diameter, hematocrit, andhemoglobin) and burrow traits(temperature, isolation, and physicalstructure). During incubation, immune responseof adult males was significantly greater than thatof females. Nestlings exhibited a lower immuneresponse than adults. Ecological and physiologicalfactors affecting immune response differed betweenadults and nestlings. General linear models showedthat immune response in adult males was positivelyassociated with burrow isolation, suggesting thatmales breeding at higher densities suffer immunesystem suppression. In contrast, immune response inchicks was positively associated with bodycondition and plasma triglyceride levels.Therefore, adult immune response appears to beassociated with social stress, whereas a trade-offbetween immune function and fasting capability mayexist for nestlings. Our results, and those fromprevious studies, provide support for anasymmetrical influence of ecological andphysiological factors on the health of differentage and sex groups within a population, and for theimportance of simultaneously considering individualand population characteristics in intraspecificstudies of immune response.

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T-cell mediated immune response (CMI) hasbeen widely studied in relation to individual andfitness components in birds. However, few studieshave simultaneously examined individual and socialfactors and habitat-mediated variance in theimmunity of chicks and adults from the samepopulation and in the same breeding season. Weinvestigated ecological and physiological variancein CMI of male and female nestlings and adults in abreeding population of Cory's Shearwaters(Calonectrisdiomedea) in theMediterranean Sea. Explanatory variables includedindividual traits (body condition, carbon andnitrogen stable isotope ratios, plasma totalproteins, triglycerides, uric acid, osmolarity,β-hydroxy-butyrate, erythrocyte meancorpuscular diameter, hematocrit, andhemoglobin) and burrow traits(temperature, isolation, and physicalstructure). During incubation, immune responseof adult males was significantly greater than thatof females. Nestlings exhibited a lower immuneresponse than adults. Ecological and physiologicalfactors affecting immune response differed betweenadults and nestlings. General linear models showedthat immune response in adult males was positivelyassociated with burrow isolation, suggesting thatmales breeding at higher densities suffer immunesystem suppression. In contrast, immune response inchicks was positively associated with bodycondition and plasma triglyceride levels.Therefore, adult immune response appears to beassociated with social stress, whereas a trade-offbetween immune function and fasting capability mayexist for nestlings. Our results, and those fromprevious studies, provide support for anasymmetrical influence of ecological andphysiological factors on the health of differentage and sex groups within a population, and for theimportance of simultaneously considering individualand population characteristics in intraspecificstudies of immune response.

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Four naphthoquinones, lapachol, a-lapachone, dehydro-a-lapachone and 4-hydroxy-a-lapachone were isolated from the ethanol extract of Zeyheria montana M. roots (Bignoniaceae) and were identified by spectroscopic methods. These naphthoquinones, except 4-hydroxy-a-lapachone, were quantified by HPLC, in the crude ethanol extracts of Z. montana roots. The separation of lapachol, a-lapachone and dehydro-a-lapachone was achieved and these compounds were identified in the chromatograms by their retention times and by their on line UV-spectra. The quantification of the three naphthoquinones, in four different samples showed medium contents of 11,0 mg of lapachol, 6,1 mg of a-lapachone and 4,3 mg of dehydro-a-lapachone, in 100 mg of Z.montana roots.

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The hexane extract of leaves of B. microphylla afforded a mixture of triterpenes esterified with fatty acids. Analyses of spectral data of the mixture and of the derivatives obtained by a transesterification reaction with NaOMe/MeOH permitted to identify the composition of the mixtures as being 24-hydroxy-urs-12-enyl 3b-eicosanate, estearate and palmitate as well as of the 24-hydroxy-olean-12-enyl 3b-eicosanate, estearate and palmitate. From the choroform and ethyl acetate extracts were isolated the oleanolic and 3b,24-dihydroxy-urs-12-en-28-oic acids, quercetin and methyl galic ester, respectively. The compounds were identified through analysis of their spectral data.

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gamma-Hydroxy-alpha-diazo-beta-ketoesters are key intermediates in the chemistry of penicilin-based antibiotics and natural products. The method developed here for the synthesis of ethyl 2-diazo-4-hydroxy-3-oxo-butanoate 17 (in two steps from the diazo mercurial 2) compares very favorably with those reported in the literature for similar compounds. The Rh2(OAc)4-mediated intramolecular OH-insertion reaction of the diazo hydroxy ester 17 was investigated, furnishing the oxetan-3-one-2-carboxilate 18 in good yield. When the diazo ester lacks a free hydroxyl group as in the case of the phenoxy diazo ester 11 an intramolecular CH-insertion takes place, affording the 2H-chromene 20 in almost quantitative yield. The behavior of other functionalized diazo esters towards Rh2(OAc)4 was also investigated.

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Eight triterpenes, maniladiol, breine, ursa-9(11):12-dien-3beta-ol, oleana-9(11):12-dien-3beta-ol, 3alpha-hydroxy-tirucalla-8,24-dien-21-oic acid, 3alpha-hydroxy-tirucalla-7,24-dien-21-oic, alpha and beta amyrines were isolated as binary mixtures obtained from the chloroform extract of the oil-resin of Protium heptaphyllum March. The identification of the compounds was based mainly in 13C NMR data and mass spectra. The diene and the tetracyclic acid triterpenes were not reported before in the literature as constituents of the studied resin.

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A monoterpene, 3beta,6beta-dihydroxy-p-menth-1-ene has been isolated from the seeds of Xylopia sericea along with four kaurane, one beyerene, one atisene and four trachylobane diterpenoids, including the trachyloban-18- and 19-methyl esters. The X-ray crystal structure of methyl ent-trachyloban-18-oate was determined in order to make an unambiguous distinction between the 18- and 19-esters. The 13C NMR data for ent-15alpha-hydroxy-trachyloban-19-oic acid has been revised.

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From the hexane extract of leaves, stem and roots, of Vellozia aff. carunculares, fourteen cleistanthane diterpenoids were detected by HRGC-MS, through the analysis of their fragmentation patterns. Comparison of their MS spectra with those of authentic standards previously isolated from other species of the family Velloziaceae allowed the identification, with a high degree of confidence, of eigth known cleistanthane diterpenoids. Of these, four were isolated and identified from their MS, IR and ¹H and 13C NMR spectra, as the known cleistantha-8,11,13-trien-7-one, cleistantha-8,11,13-trien-3,7-dione, cleistantha-1,8,11,13-tetraen-3,7-dione and the first reported 6-alpha-hydroxy-cleistantha-8,11,13-trien-7-one. The triterpenoid beta-amyrin was also isolated.

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In the Brazilian Complete Spacial Mission, the research of Vehicle Satellite Launcher is important. The solid propellant composite used in this vehicle is made with ammonium perchlorate, aluminiun powder and hydroxy terminated polibutadiene resin. In the propellant the bonding agent has a function to promote the interaction between solids and polimeric matrix, improving mechanical properties as stress, strain, aging characteristics and moisture embrittlement. Due its importance in propellant, bonding agent is consider as industrial secret and the literature about it is generic, without greater informations.

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The reaction between hydroxy-terminated polybutadiene and isophorone diisocyanate constitutes the base of the curing process of the most composite solid propellant used in the propulsion of solid rocket propellant. In this work, differential scanning calorimetry and viscosity measurements were used to evaluate the effect of the ferric acetylacetonate catalyst concentration on the reaction between HTBR and IPDI. These analyses show one exotherm, which shifts to lower temperatures as the catalyst concentration increases. The viscosity analyses show that the increase of temperature causes, at first, a reduction in the mixture viscosity, reaching a minimum range called gelification region (increasing the crosslinking density).

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Chemical investigation of the leaves of Styrax camporum (Styracaceae) resulted in the isolation of the lignan lariciresinol and six triterpenes: ursolic acid, 2alpha,3alpha-dihydroxy-urs-12-en-28-oic acid and mixtures of uvaol and erythrodiol, as well as 3beta-O-trans-p-coumaroyl-2alpha-hydroxy-urs-12-en-28-oic acid and 3b-O-trans-p-coumaroylmaslinic acid. The structures of these compounds were established by spectroscopic analysis. This paper deals with the first report of these compounds in S. camporum.

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A rapid, expedient and enantioselective method for the synthesis of beta-hydroxy amines and monosubstituted aziridines in up to 99% e.e., via asymmetric transfer hydrogenation of a-amino ketones and cyclisation through treatment with tosyl chloride and base, is described. (1R,2R)-N-(para-toluenesulfonyl)-1,2-ethylenediamine with formic acid has been utilised as a ligand for the Ruthenium (II) catalysed enantioselective transfer hydrogenation of the ketones.The chiral 2-methyl aziridine, which is a potentially more efficient bonding agent for Rocket Solid Propellant has been successfully achieved.

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In an ethanolic extract of leaves of Ottonia corcovadensis (Piperaceae) were identified sixteen terpenoids of essential oil and the three flavonoids 3',4',5,5',7-pentamethoxyflavone (1), 3',4',5,7-tetramethoxyflavone (2) and 5-hydroxy-3',4',5',7-tetramethoxyflavone (3) and cafeic acid (4). Two amides (5 and 6) were isolated from an ethanolic extract of the roots. The structures were established by spectral analysis, meanly NMR (1D and 2D) and mass spectra. Extensive NMR analysis was also used to complete ¹H and 13C chemical shift assignments of the flavonoids and amides. The components of the essential oil were identified by computer library search, retention indices and visual interpretation of mass spectra.

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The essential oils from leaves, root bark and root wood of Cochlospermum vitifolium were investigated for the first time. The oils were obtained by hydrodistillation and analyzed by GC/MS. The main volatile constituents were beta-caryophyllene (8.2 - 46.5%), beta-bisabolene (11.5 - 29.3%), gamma-muurolene (28.4%), alpha-humulene (26.0%), 1-hydroxy-3-hexadecanone (16.2 - 19.5%) and beta-pinene (10.6%). Phytochemical analysis of the root bark and root wood extracts yielded excelsin, pinoresinol, narigenin, aromadendrin, galic acid and a triacylbenzene, along with beta-sitosterol and stigmasterol and their D-glucosides. The structures of all compounds were determined by analyses of the spectroscopic data (NMR and MS), and comparison with the literature.

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Memora peregrina (local name: 'ciganinha' - Bignoniaceae) is a weed that often invades pastures in the Brazilian state of Mato Grosso do Sul. From its leaves and subterranean parts, the following compounds were isolated: allantoin (20.7 w/w in subterranean parts), the iridoid 6beta-hydroxyipolamiide, hyperin, 3'-O-methylhyperin, 4-hydroxy-N-methylproline, beta-sitosterol, alpha-amirin and beta-amirin, and lupeol. Allantoin exhibited an activity of inducing germination in seeds of Lactuca sativa used as a biological model, and the iridoid showed moderate activity in the larval development of Anagasta kuehniella. These results, associated with this plant's behavior, are suggestive of the occurrence of adaptive and competitive strategies in relation to other plant species.