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1.
Carbohydr Res ; 426: 33-9, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27058294

RESUMO

2-Azido-2-deoxy-1-thioglucoside donors with an electron withdrawing group at position 6 were employed to study the stereoselectivity of the glycosylation reaction with several acceptors, ranging from unhindered small primary alcohols to other sugars and steroids, using NIS/TfOH as promoter. p-Tolyl 2-azido-3,4-di-O-benzyl-6-O-chloroacetyl-2-deoxy-1-thio-α/ß-D-glucopyranoside afforded the higher α-selectivity, showing that a stronger electron withdrawing ester at O-6 influenced the anomeric selectivity towards the 1,2-cis glucosides. The anomeric stereoselectivity was highly dependent on the acceptor.


Assuntos
Álcoois/química , Carboidratos/química , Esteroides/química , Tioglucosídeos/química , Configuração de Carboidratos , Glicosilação , Estereoisomerismo
2.
Braz J Biol ; 70(4): 1047-53, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21180912

RESUMO

Phyllostomus hastatus bat is species broadly distributed over the Neotropical region, which uses as diurnal roosts caves, hollow trees, palm leaves and human buildings. Thirteen diurnal roosts of P. hastatus were analysed from 1990 to 2009 in several localities of Rio de Janeiro State, regarding environment (rural, urban or protected area), type of roost (hollow tree, basement or roof), sex ratio and cohabitation. A nocturnal roost was also analysed. Sex ratio of P. hastatus varied considerably among roosts what may be explained by the fact this species can roost alone, in couples, in harems or in groups of bachelor males. Phyllostomus hastatus was observed in cohabitation with three other species: Molossus rufus, Molossus molossus and Myotis nigricans. Due to the frequency of cohabitation observed between P. hastatus and species of the genus Molossus, one or more advantages for the members of this association may be expected. The simultaneous usage of a feeding roost by a group of bachelor males is unknown information in the literature, and may suggest that this kind of group may interact with each other even when away from their diurnal roosts.


Assuntos
Comportamento Animal/fisiologia , Quirópteros/fisiologia , Abrigo para Animais/classificação , Razão de Masculinidade , Animais , Quirópteros/classificação , Feminino , Masculino
3.
Braz J Biol ; 70(3): 511-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20730337

RESUMO

Few sites have been well sampled for bats, and samplings in islands are even scarcer. Therefore, the objectives of the present study were: (1) to list the bat species of Ilha da Marambaia; (2) to compare richness, abundance and biomass of bat guilds found there; (3) to analyse abundance patterns of bat species; and (4) to compare richness, abundance and composition of the bat fauna among different kinds of environment. To capture bats we used mist nets set in five different environments, totalising 3559.2 net-hours, during 37 nights between October 2006 and August 2008. A total of 1,133 captures were accomplished, comprising 34 species from five families. The most abundant species was Molossus molossus. Frugivorous bats exhibited higher richness, abundance and biomass if compared to other guilds. Most species (N = 22) exhibited abundances between 1 to 10% of all captures. Sixteen species were restricted to just one of the environments sampled. The high richness may be attributed to sampling carried out in several environments, and to the capture of insectivorous species over water bodies.


Assuntos
Biodiversidade , Biomassa , Quirópteros/classificação , Animais , Brasil , Densidade Demográfica
4.
Braz. j. biol ; 70(3): 511-519, Aug. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-555262

RESUMO

Few sites have been well sampled for bats, and samplings in islands are even scarcer. Therefore, the objectives of the present study were: (1) to list the bat species of Ilha da Marambaia; (2) to compare richness, abundance and biomass of bat guilds found there; (3) to analyse abundance patterns of bat species; and (4) to compare richness, abundance and composition of the bat fauna among different kinds of environment. To capture bats we used mist nets set in five different environments, totalising 3559.2 net-hours, during 37 nights between October 2006 and August 2008. A total of 1,133 captures were accomplished, comprising 34 species from five families. The most abundant species was Molossus molossus. Frugivorous bats exhibited higher richness, abundance and biomass if compared to other guilds. Most species (N = 22) exhibited abundances between 1 to 10 percent of all captures. Sixteen species were restricted to just one of the environments sampled. The high richness may be attributed to sampling carried out in several environments, and to the capture of insectivorous species over water bodies.


Poucos são os locais satisfatoriamente amostrados para morcegos e menos ainda as ilhas. Os objetivos deste estudo foram listar as espécies de morcegos da Ilha da Marambaia, comparar a riqueza, abundância e biomassa das guildas de morcegos encontradas, analisar o padrão de abundância das espécies de morcegos e comparar a riqueza, abundância e composição entre os diferentes ambientes amostrados. O método de amostragem consistiu do uso de redes de neblina armadas em cinco ambientes diferentes, totalizando 3559,2 redes-hora, em 37 noites entre outubro de 2006 e agosto de 2008. Foram obtidas 1.133 capturas, compreendendo 34 espécies de cinco famílias. A espécie mais abundante foi Molossus molossus. Os frugívoros apresentaram maior riqueza, abundância e biomassa. A maior parte das espécies (N = 22) apresentou abundâncias entre 1 e 10 por cento do total de capturas. Dezesseis espécies foram restritas a apenas um dos ambientes amostrados. A elevada riqueza encontrada pode ser atribuída à realização de coletas em vários ambientes, e a captura de espécies insetívoras sobre a água.


Assuntos
Animais , Biodiversidade , Biomassa , Quirópteros/classificação , Brasil , Densidade Demográfica
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