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Souza F.B.,University of Sao Paulo | Pimenta D.C.,Instituto Butanta | Stefani H.A.,University of Sao Paulo
Tetrahedron Letters | Year: 2016

A general and efficient methodology for the synthesis of novel triazoles has been developed based on a microwave-assisted multicomponent reaction involving α-thio aldehyde and propargylamine, with the formation of an imine that in situ reacts with organoazides by copper-catalyzed [3+2] azides-alkyne cycloaddition (CuAAC). The reaction results in a small library of imine 1,4-disubstituted 1,2,3-triazoles. © 2016 Elsevier Ltd.


Goncalves-Souza T.,São Paulo State University | Brescovit A.D.,Instituto Butanta | Rossa-Feres D.D.C.,São Paulo State University | Romero G.Q.,São Paulo State University
Journal of Arachnology | Year: 2010

Although bromeliads can be important in the organization of invertebrate communities in Neotropical forests, few studies support this assumption. Bromeliads possess a three-dimensional architecture and rosette grouped leaves that provide associated animals with a good place for foraging, reproduction and egg laying, as well as shelter against desiccation and natural enemies. We collected spiders from an area of the Atlantic Rainforest, southeastern Brazil, through manual inspection in bromeliads, beating trays in herbaceousshrubby vegetation and pitfall traps in the soil, to test if: 1) species subsets that make up the Neotropical forest spider community are compartmentalized into different habitat types (i.e., bromeliads, vegetation and ground), and 2) bromeliads are important elements that structure spider communities because they generate different patterns of abundance distributions and species composition, and thus amplify spider beta diversity. Subsets of spider species were compartmentalized into three habitat types. The presence of bromeliads represented 41 of the increase in total spider richness, and contributed most to explaining the high beta diversity values among habitats. Patterns of abundance distribution of the spider community differed among habitats. These results indicate that bromeliads are key elements in structuring the spider community and highlight the importance of Bromeliaceae as biodiversity amplifiers in Neotropical ecosystems. © 2010 The American Arachnological Society.


Ali B.,University of Sao Paulo | Zukerman-Schpector J.,Federal University of São Carlos | Ferreira F.P.,University of Sao Paulo | Shamim A.,University of Sao Paulo | And 2 more authors.
Tetrahedron Letters | Year: 2015

The cyclodimerization reaction of N-substituted-5-hydroxy-pyrrolydinones promoted by BF3·Et2O and HCl to obtain symmetrical 1,4-dioxane derivatives was achieved in moderate to good yields, mild conditions, and short reaction times. These transformations render a promising alternative route that provides access to diverse 1,4-dioxane derivatives with a wide structural diversity. © 2015 Elsevier Ltd.


Souza F.B.,University of Sao Paulo | Shamim A.,University of Sao Paulo | Argomedo L.M.Z.,University of Sao Paulo | Pimenta D.C.,Instituto Butanta | Stefani H.A.,University of Sao Paulo
Molecular Diversity | Year: 2015

An efficient methodology for the synthesis of aryl-substituted vinyl sulfoxides through direct substitution of aryl-substituted alkynyl grignard reagents on menthyl-p-toluenesulfinate followed by Suzuki–Miyaura cross-coupling reaction has been developed. It has also been described that the reaction of alkyl-substituted and cycloalkyl-substituted alkynyl grignard reagents with menthyl-p-toluenesulfinate led to two products, i.e., alkynyl sulfoxide derivatives, as a result of substitution, and enyne sulfoxide derivatives, which resulted from substitution followed by Michael type addition. It was possible to selectively synthesize the enyne sulfoxide derivatives by changing the concentration of the grignard reagent. These alkenyl sulfoxides were transformed into the corresponding (Formula presented.)-thio aldehydes in high yields via additive Pummerer rearrangement. © 2015 Springer International Publishing Switzerland


Lula I.,Federal University of Minas Gerais | De Sousa F.B.,Federal University of Minas Gerais | Denadai A.M.L.,Federal University of Minas Gerais | Ianzer D.,Federal University of Minas Gerais | And 4 more authors.
Journal of the Brazilian Chemical Society | Year: 2011

The BPP7a heptapeptide, p-Glu1Asp2Gly 3Pro4Ile5Pro6Pro7, forms an association complex with β-cyclodextrin in a 1:1 molar ratio. The peptide and its complex were characterized by circular dichroism (CD) and isothermal titration calorimetry (ITC), which showed a very weak interaction between the ?-cyclodextrin and the peptide. Assignments of all hydrogen resonances of the peptide alone and as a complex were made using 1H nuclear magnetic resonance (NMR) experiments at 400 and 600 MHz. High resolution diffusion ordered spectroscopy (HR-DOSY) experiments were carried out to establish the self-aggregation state of BPP7a. It was also shown that the β-cyclodextrin breaks the molecular clusters leading to complex formation. In addition, the anti-hypertensive activity of the BPP7a/β-cyclodextrin complex was evaluated in spontaneous hypertensive rats (SHR), showing increased activity compared to that of pure BPP7a. ©2011 Sociedade Brasileira de Química.


Vizzotto-Martino R.M.B.,University of West Paulista | Bonancea C.C.A.V.,University of West Paulista | De Souza Geroti T.C.,Discente de Medicina Veterinaria | Frazati-Gallina N.M.,Instituto Butanta | And 2 more authors.
Semina:Ciencias Agrarias | Year: 2016

This study evaluated the effects of supplementation with a combination of probiotic microorganisms, added at different concentrations to the mineral mixture, on the production of serum antibodies against rabies virus in cattle vaccinated with a single dose of rabies vaccine. Forty-two male Nellore cattle, aged 12 months, were randomly divided into three groups (n = 14): the control group (CG) received 70 grams of mineral mixture/animal/day; and the 2 gram probiotic group (G2P) and 8 gram probiotic group (G8P) received 70 grams of mineral mix/animal/day with 2 and 8 grams added, respectively, of a combination of probiotic microorganisms (Lactobacillus acidophilus, Streptococcus faecium, Bifidobacterium thermophilum and Bifidobacterium longum). Individual antibody titers were determined using a neutralization in cell-based rapid fluorescent focus inhibition test (RFFIT) technique. One-way analysis of variance (one-way ANOVA) was used with contrasts using the Tukey method to determine whether the experimental groups differed within each time point, and the paired t-test was used to determine whether differences occurred between time points within each group. The level of significance was set at 5%. There were statistically significant differences between the mean serum concentrations of the CG and G8P groups at 30 and 60 days after the first vaccination, and at 60 days, 100% of the animals maintained minimum titers of protective antibodies only in the G8P group. There was also improvement in the production of antibodies in the G2P group compared with the CG after 30 and 60 days, but this difference was not statistically significant. In conclusion, increasing doses of probiotic added to the mineral mix beneficially affected the rabies humoral immune response, as determined by serum antibodies, and enabled the maintenance of minimum protective titers for a longer period in previously vaccinated cattle.


Gamarra L.F.,Hospital Israelita Albert Einstein IIEPAE | Gamarra L.F.,University of Sao Paulo | Mamani J.B.,University of Sao Paulo | Carneiro S.M.,Instituto Butanta | And 7 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2010

The present work is a report of the characterization of superparamagnetic iron oxide nanoparticles coated with silicone used as a contrast agent in magnetic resonance imaging of the gastrointestinal tract. The hydrodynamic size of the contrast agent is 281.2 nm, where it was determined by transmission electron microscopy and a Fe 3O 4 crystalline structure was identified by X-ray diffraction, also confirmed by Mossbauer Spectroscopy. The blocking temperature of 190 K was determined from magnetic measurements based on the Zero Field Cooled and Field Cooled methods. The hysteresis loops were measured at different temperatures below and above the blocking temperature. Ferromagnetic resonance analysis indicated the superparamagnetic nature of the nanoparticles and a strong temperature dependence of the peak-to-peak linewidth δH pp, giromagnetic factor g, number of spins N s and relaxation time T 2 were observed. This behavior can be attributed to an increase in the superexchange interaction. Copyright © 2010 American Scientific Publishers. All rights reserved.


PubMed | Instituto Butanta and University of Sao Paulo
Type: Journal Article | Journal: Molecular diversity | Year: 2015

An efficient methodology for the synthesis of aryl-substituted vinyl sulfoxides through direct substitution of aryl-substituted alkynyl grignard reagents on menthyl-p-toluenesulfinate followed by Suzuki-Miyaura cross-coupling reaction has been developed. It has also been described that the reaction of alkyl-substituted and cycloalkyl-substituted alkynyl grignard reagents with menthyl-p-toluenesulfinate led to two products, i.e., alkynyl sulfoxide derivatives, as a result of substitution, and enyne sulfoxide derivatives, which resulted from substitution followed by Michael type addition. It was possible to selectively synthesize the enyne sulfoxide derivatives by changing the concentration of the grignard reagent. These alkenyl sulfoxides were transformed into the corresponding [Formula: see text]-thio aldehydes in high yields via additive Pummerer rearrangement.

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