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Search Results: 1 - 10 of 5245 matches for " Celso Amorim Camara "
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Identification of Sugar, Amino Acids and Minerals from the Pollen of Jandaíra Stingless Bees (Melipona subnitida)  [PDF]
Girliane Regina da Silva, Tamires Botelho da Natividade, Celso Amorim Camara, Eva Monica Sarmento da Silva, Francisco de Assis Ribeiro dos Santos, Tania Maria Sarmento Silva
Food and Nutrition Sciences (FNS) , 2014, DOI: 10.4236/fns.2014.511112

The aim of this investigation was to analyze two samples of pollen from jandaíra stingless bees (Melipona subnitida) in view of their mineral composition, free amino acids and sugars. Palynological analysis showed that the predominant pollen was monofloral from Senna sp. species (94.5%, pollen 2011) and the second pollen sample showed the presence of two primary species, Chamaecrista sp. (39.2% pollen 2009) and Mimosa tenuiflora (43.5%) (pollen 2009). The highest mineral content was potassium. The bee pollen contained 20.8% and 31.0% of mannitol in samples from 2011 and 2009, respectively. Proline and serine are the predominant amino acids. High content of essential amino acids, minerals and the sugar mannitol confirmed high nutritional value of pollen samples from jandaíra bees.

Feoforbídeo (etoxi-purpurina-18) isolado de Gossypium mustelinum (Malvaceae)
Silva, Tania Maria Sarmento;Camara, Celso Amorim;Barbosa-Filho, José Maria;Giulietti, Ana Maria;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000300015
Abstract: the phaeophorbide ethyl ester named purpurin-18 and the flavonoids quercetin and kaempferol were obtained by chromatographic procedures from the chloroform fraction of aerial parts of gossypium mustelinum. the structure of these compound was determined by nmr, ir and mass spectra data analysis. this is the first occurrence of this compound in angiosperm.
Synthesis of 1,4-naphthoquinone derivatives using 1,3-dipolar cycloaddition and Sonogashira reactions Síntese de derivados da 1,4-naftoquinona utilizando a rea o de cicloadi o 1,3-dipolar e a rea o de Sonogashira
Wilson Silva do Nascimento,Mauro Gomes da Silva,Ronaldo Nascimento de Oliveira,Celso Amorim Camara
Orbital : the Electronic Journal of Chemistry , 2010,
Synthesis of 1,4-naphthoquinone derivatives using 1,3-dipolar cycloaddition and Sonogashira reactions
Wilson Silva do Nascimento,Mauro Gomes da Silva,Ronaldo Nascimento de Oliveira,Celso Amorim Camara
Orbital : the Electronic Journal of Chemistry , 2010,
Abstract: Naphthoquinones are known according to their important bio-activities, such as their antitumoral and topoisomerase inhibition properties. From 2-azido (3) or 2,3-diacetylene-1,4-naphthoquinone (4) it was possible to obtain triazole derivatives (naphthoquinonic). This work describes the synthesis of two novel molecules, with triazole groups linked to 1,4-naphthoquinone using the 1,3-dipolar cycloaddition and Sonogashira reactions. The synthetic strategy followed two routes (Scheme 1). First, we synthesized the 2-bromo-1,4-naphthoquinone (2, yield 98%) by using Br2 and CH3CO2H, and then used it to obtain 2-azido-1,4-naphthoquinone (3, yield 62%) from compound 1, along with ethanolic solution (reflux) and NaN3. Finally, we prepared 1,2,3-triazole compounds (4a, b) by 1,3-dipolar cycloaddition, involving compound (3) and terminal acetylenes (phenylacetylene, a) and glycoside (b) using Cu(OAc)2 and ascorbate, under argon atmosphere. During the second step, 2,3-dibromo-1,4-naphthoquinone was prepared using Br2/CH2Cl2 at room temperature. From compound (5) it was possible to synthesize (6), catalyzed by Pd(PPh3)2Cl2/CuI/Et3N, under argon atmosphere, in 40% yield. The 1,3-dipolar cycloaddition reactions involving 2-azido-1,4-naphthoquinone (3) and alkynes (a, yield 23% and b, yield 30%) were conducted using the solvent system, (1:1) terc-BuOH/H2O/r.t/ 20 mol% of Cu(OAc)2 and sodium ascorbate, under stirring during 24 hours. The reaction involving 2,3-dibromo-1,4-naphthoquinone (5, yield 65%) and phenylacetylene was prepared using the solvent mixture (2:1) DMSO/CHCl3 and catalytic amount of CuI/Pd(PPh3)2Cl2. The final products were characterized by elemental analysis and spectrometric techniques (IR, NMR 1H and 13C). Two novel triazole compounds were synthesized from naphthoquinones by 1,3-dipolar cycloaddition from suitable 1,4-naphthoquinones obtained by Sonogashira couplings.
Brazilian foreign policy under President Lula (2003-2010): an overview
Amorim, Celso;
Revista Brasileira de Política Internacional , 2010, DOI: 10.1590/S0034-73292010000300013
Abstract: foreign minister of brazil since 2003, ambassador celso amorim outlines the main guidelines and accomplishments of brazil's foreign policy under president luiz inácio lula da silva. the article provides a full-fledged, although not exhaustive, narrative of a number of diplomatic initiatives championed by brazil over the last eight years: from the gathering of the group of developing countries in a world trade organization (wto) meeting in cancun to the negotiations that led to the declaration of tehran, as well as the challenges the country has been facing as its international weight grows.
Estrategia de defensa de Brasil y de América del Sur Defense Strategy of Brazil and South America
Revista de Ciencia Política , 2012,
Uma vis o brasileira do panorama estratégico global
Celso Amorim
Contexto Internacional , 2011, DOI: 10.1590/s0102-85292011000200001
Doen?as do trabalho: exclus?o, segrega??o e rela??es de gênero
Salim, Celso Amorim;
S?o Paulo em Perspectiva , 2003, DOI: 10.1590/S0102-88392003000100003
Abstract: using as its basis a general overview of work-related accidents and illnesses, this article analyzes the evolution and social and demographic characteristics of the ler/dort in the rmbh in the 1990s. to this end, consideration is given to the dynamics of the labor market and the underlying mechanisms of exclusion and segregation, ultimately identifying specific situations and unique consequences affecting worker health according to occupational type.
Synthesis of 2-hydroxy-3-(2-methyl-propenyl)-1,4-naphthoquinone and related oxime derivatives Síntese de 2-hidroxi-3-(2-metil-propenil)-1,4-naftoquinona e oximas relacionadas
Patricia S. Oliveira,Celso A Camara
Orbital : the Electronic Journal of Chemistry , 2012,
Abstract: The condensation reaction of commercial 2-hydroxy-1 ,4-naphthoquinone 1 (lawsone) with isobutyraldehyde 2 furnishs norlapachol 3 (2-hydroxy-3-(2-methyl-propenyl) -1,4-naphthoquinone) with yields ranging from 66 to 93% depending on the different conditions tested, and a reaction temperature factor determinant for the formation of the desired product. It was treated with hydroxylamine hydrochloride in alkaline (NaOH) to provide the oxime 4 from regioselective modification of the carbonyl C-1 with 91% yield. The regioselectivity of the reaction can be explained by analyzing the different resonance structures which can be seen that the carbonyl C-4 is less electrophilic than C-1. In this work was also obtained the oxime 5, 6 and 7 from lapachol, αlpha and β-lapachone, respectively, in yields of 64-85%. The oximes of αlpha and β-norlapachone, 8 and 9 are in obtention. All the products were analyzed by IR and NMR, and were observed that oximes of lapachol and norlapachol are isolated as E/Z mixtures. Two-dimensional NOE-type experiments of the corresponding acylated derivative will be made to help identify the proportion of the mixture. A partir de rea es de condensa o da 2-hidroxi-1,4-naftoquinona 1 comercial (lausona) com o isobutiraldeído 2 foi possível obter o norlapachol 3 (2-hidroxi-3-(2-metil-propenil)-1,4-naftoquinona) com rendimentos que variaram 66 a 93% em fun o das diferentes condi es testadas, sendo a temperatura reacional um fator determinante para a forma o do produto desejado. O mesmo foi tratado com cloridrato de hidroxilamina em meio básico (NaOH) fornecendo a oxima 4 a partir da modifica o regiosseletiva na carbonila C-1 com rendimento de 91%. A regiosseletividade da rea o pode ser explicada através da análise das diferentes estruturas de ressonancia onde se observa que o carbono C-4 da carbonila tem menor caráter eletrofílico em compara o ao carbono C-1. Foram obtidas também as oximas 5, 6 e 7 partindo-se do lapachol, da α e da β-lapachona respectivamente em rendimentos de 64 a 85%, e as oximas da α e da β-norlapachona, 8 e 9 respectivamente, est o em fase de obten o. Os produtos obtidos tiveram suas estruturas elucidadas por meio de técnicas espectroscópicas de IV e RMN 1H e 13C e, verificou-se que ao contrário das oximas das lapachonas, as oximas do lapachol e do norlapachol s o isoladas como misturas de E/Z. Experimentos bidimensionais do tipo NOE em derivados acetilados correspondentes ser o realizados para auxiliar a identifica o da propor o da mistura.
A new class of phthalimido-quinones synthesis Síntese de uma nova classe de ftalimido-quinonas
Jeziane S. Alves,Josinete A. Paz,Celso A. Camara
Orbital : the Electronic Journal of Chemistry , 2012,
Abstract: Four new Michael adducts from the reaction between 1,4-naphthoquinone and 2,3-dibromo-1,4-naphthoquinone with w-amino-N-alkylphthalamide derivatives were presented in this work. The products named 2a-c were completed assigned on the basis of 13C, 1HNMR, IR and elemental analysis, still remaining spectroscopy data of 3a product (n=4). The global yields of 2a-c (n=3, 4 e 6) and 3a(n=4), was respectively 41%, 39 %, 27% and 30%.The yields are low probably due the formation of dimeric by-products. A new methodology has been employed to obtain the key-intermediates w-amino-N-alkylphthalamide (4a-b), using bromide alkylphthalamide (6a-b) (n=3-4) to obtain the corresponding azides (5a-b) with 85% and 90% yields, followed by catalytic hydrogenation with the use of palladium on charcoal 10% to obtain w-amino-N-alkylphthalamide (4a-b) with respectively 90% e 60% yields, as a more viable synthesis route. O presente trabalho apresenta a síntese de quatro compostos inéditos a partir da adi o de Michael à 1,4-naftoquinona e à 2,3-dibromo-1,4-naftoquinona a partir de w-amino-N-alquilftalimidas (n=3,4 e 6). Os produtos 2a-c já foram elucidados através das técnicas espectroscópicas de Infravermelho, RMN 1H, RMN 13C e análise elementar, restando ainda os dados espectroscópicos do produto 3a (n=4). Os rendimentos globais dos produtos 2a-c (n=3, 4 e 6) e 3a (n=4) foram 41%, 39%, 27%, e 30%, respectivamente. Os rendimentos s o baixos, visto que na primeira etapa, há a forma o de um produto dimérico. Diante disso, uma nova metodologia tem sido empregada para obten o dos intermediários-chave w-amino-N-alquilftalimidas (4a-b). A partir de alquil-ftalimidas bromadas (6a-b) (n=3-4), obtêm-se as azidas (5a-b) (n=3-4) com rendimento de 85% e 90% respectivamente, seguida da rea o de hidrogena o catalítica por meio de paládio/carbono (10%) para obten o de w-amino-N-alquilftalimidas com rendimento de 90% e 60%, respectivamente, o que tornará mais viável a síntese das moléculas-alvo.
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