Search Results - "Silva, Gil Valdo José da"

One-step synthesis of indanones through NbCl5-induced Friedel–Crafts reaction by da Silva Barbosa, Jader, da Silva, Gil Valdo José, Constantino, Mauricio Gomes

“…[Display omitted] This Letter describes the use of NbCl5 as the Lewis acid in Friedel–Crafts reactions, in which a bifunctional electrophile reacts inter- and…”
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Side-chain modifications of highly functionalized 3(2H)-furanones by Nardini, Viviani, Machado Rodrigues, Shirley Muniz, Constantino, Maurício Gomes, da Silva, Gil Valdo José

“…A series of 3(2H)-furanones, based on side-chain modifications of a parent 3(2H)-furanone, was synthesized in good yield. The parent compound was prepared by…”
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Citronellal assumes a folded conformation in solution due to dispersion interactions: A joint NMR-DFT analysis by Nardini, Viviani, Dias, Luis Gustavo, Palaretti, Vinicius, da Silva, Gil Valdo José

“…Citronellal, an acyclic monoterpenoid, is a small molecule suitable for systematic scanning of its conformational geometric parameters in solution or in the…”
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Enantiomeric quantification of amines by 1H and 13C NMR: First report of S-citronellal as chiral derivatization agent (CDA) by Nardini, Viviani, Palaretti, Vinicius, da Silva, Gil Valdo José

“…The possibility of determining enantiomeric excess (ee) in chiral compounds by nuclear magnetic resonance (NMR) was discovered half a century ago and remains…”
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Stereochemical assignment of four diastereoisomers of a maculalactone derivative by computational NMR calculations by Previdi, Daniel, Nardini, Viviani, Rosa, Mayla Eduarda, Palaretti, Vinicius, da Silva, Gil Valdo José, Donate, Paulo Marcos

“…Naturally occurring γ-butyrolactones and their synthetic analogues display a wide range of bioactivities. Here, the multicomponent reaction of dimethyl…”
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N, N′, N″-trisubstituted guanidines: Synthesis, characterization and evaluation of their leishmanicidal activity by do Espírito Santo, Rafael Dias, Velásquez, Ángela María Arenas, Passianoto, Luana Vitorino Gushiken, Sepulveda, Alex Arbey Lopera, da Costa Clementino, Leandro, Assis, Renata Pires, Baviera, Amanda Martins, Kalaba, Predrag, dos Santos, Fábio Neves, Éberlin, Marcos Nogueira, da Silva, Gil Valdo José, Zehl, Martin, Lubec, Gert, Graminha, Márcia Aparecida Silva, González, Eduardo René Pérez

“…Leishmaniasis is a group of diseases caused by protozoan parasites from the genus Leishmania. There are estimated 1.3 million new cases annually with a…”
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An Explanation about the Use of (S)-Citronellal as a Chiral Derivatizing Agent (CDA) in 1H and 13C NMR for Sec-Butylamine, Methylbenzylamine, and Amphetamine: A Theoretical-Experimental Study by Nardini, Viviani, Palaretti, Vinicius, Dias, Luis, da Silva, Gil

“…A chiral derivatizing agent (CDA) with the aldehyde function has been widely used in discriminating chiral amines because of the easy formation of imines under…”
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Conformational dynamics of 4-formylaminoantipyrine based on NMR and theoretical calculations by Silva, Simone Cavalcante, Rodrigues, Shirley M.M., Nardini, Viviani, Vaz, Artur de L.L., Palaretti, Vinicius, da Silva, Gil Valdo José, Vessecchi, Ricardo, Clososki, Giuliano C.

“…We investigated the metamizole metabolite 4-formylaminoantipyrine (4-FAA) by 1H dynamic nuclear magnetic resonance. 4-FAA exhibits a carbon-nitrogen partial…”
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High stereoselectivity on low temperature Diels-Alder reactions by da Silva Filho, Luiz Carlos, Lacerda Júnior, Valdemar, Constantino, Mauricio Gomes, da Silva, Gil Valdo José, Invernize, Paulo Roberto

“…We have found that some of the usually poor dienophiles (2-cycloenones) can undergo Diels-Alder reaction at -78 degrees C with unusually high stereoselectivity…”
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Synthesis and dopamine receptor binding of dihydrexidine and SKF 38393 catecholamine-based analogues by da Silva, Suzane Rosa, Kalaba, Predrag, Fabišiková, Anna, Zehl, Martin, Dragačević, Vladimir, dos Anjos, Luana Ribeiro, Neill, Philip John, Wieder, Marcus, Prado-Roller, Alexander, Gajic, Natalie, Palaretti, Vinicius, da Silva, Gil Valdo Jose, Pifl, Christian, Lubec, Gert, Gonzalez, Eduardo R. Perez

“…Dopamine is an important neurotransmitter that regulates numerous essential functions, including cognition and voluntary movement. As such, it serves as an…”
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Cytotoxic alkaloids from Pogonopus tubulosus: G2/M cell cycle arrest and inhibition of DNA topoisomerase IIα by isotubulosine by Filippin, Kelly Juliana, Portela, Aymee, Rodrigues, Edilene Delphino, Matos, Maria de Fátima Cepa, Silva, Gil Valdo José, Garcez, Walmir Silva, Garcez, Fernanda Rodrigues, Perdomo, Renata Trentin

“…Phytochemical investigation of Pogonopus tubulosus trunk led to the isolation of isotubulosine and alangiside, tetrahydroisoquinoline indolic monoterpene…”
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Post-column sodiation to enhance the detection of polyacetylene glycosides in LC–DAD–MS analyses: an example from Bidens gardneri (Asteraceae) by Silva, Denise Brentan, Rodrigues, Edilene Delphino, da Silva, Gil Valdo José, Lopes, Norberto Peporine, de Oliveira, Dionéia Camilo Rodrigues

“…The use of liquid chromatography–electrospray ionization–mass spectrometry (LC–ESI–MS) in dereplication studies of medicinal plants is a common strategy, but…”
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Synthesis of 1-methyl-3-oxo-7-oxabicyclo[2.2.1]hept-5-ene-2-carboxylic acid methyl ester by Aragão, Valquiria, Constantino, Mauricio Gomes, Beatriz, Adilson, José da Silva, Gil Valdo

“…A simple and efficient method for the preparation of 1-methyl-3-oxo-7- oxabicyclo[2.2.1]hept-5-en-2-carboxylic acid methyl ester (1) is described. The first…”
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Synthesis of the bicyclo[6.2.1]undecane ring system by a solvent-free Diels–Alder reaction by Beatriz, Adilson, Gomes, Roberto da Silva, Constantino, Mauricio Gomes, da Silva, Gil Valdo José, de Oliveira, Kleber Thiago

“…•A short synthetic route to bicyclo[6.2.1]undecane ring system is presented.•In this approach, we use as a key step a solvent-free Diels–Alder reaction.•The…”
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DOSY NMR applied to analysis of flavonoid glycosides from Bidens sulphurea by Rodrigues, Edilene Delphino, da Silva, Denise Brentan, de Oliveira, Dionéia Camilo Rodrigues, da Silva, Gil Valdo José

“…2D DOSY 1H NMR has proved to be a useful technique in the identification of the molecular skeleton of the four major compounds of ethyl acetate extract of…”
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Detailed 1H and 13C NMR structural assignment of three biologically active lignan lactones by Heleno, Vladimir Constantino Gomes, Silva, Rosangela da, Pedersoli, Susimaire, Albuquerque, Sérgio de, Bastos, Jairo Kenupp, Silva, Márcio Luis Andrade e, Donate, Paulo Marcos, Silva, Gil Valdo José da, Lopes, João Luis Callegari

“…In this paper we present a complete 1H and 13C NMR spectral analysis of three lignan lactones (methylpluviatolide, dimethylmatairesinol and hinokinin) by the…”
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Racemic synthesis of 1,2-secomicrominutinin by Silva, Rosangela da, Donate, Paulo Marcos, Silva, Gil Valdo José da, Pedersoli, Susimaire, Alemán, Carlos

“…The racemic 1,2-secomicrominutinin (25) was synthesized employing the intramolecular cycloaddition reaction of an (alkenyloxy)ketene, prepared from the…”
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Assignment of NMR data and relative stereochemistry determination of paraconic acid derivatives by Rodrigues, Shirley Muniz Machado, Nardini, Viviani, Moral, Raphael Fernando, Constantino, Mauricio Gomes, da Silva, Gil Valdo José

“…[Display omitted] •The four paraconic acid derivatives had their structures fully elucidated.•A complete 1H and 13C NMR structural assignment was…”
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Opening of Epoxide Rings Catalyzed by Niobium Pentachloride by Constantino, Mauricio Gomes, Júnior, Valdemar Lacerda, Invernize, Paulo Roberto, Filho, Luiz Carlos da Silva, José da Silva, Gil Valdo

“…The behavior of several epoxides when treated with NbCl 5 was studied. In general, the studied epoxides reacted rapidly with NbCl 5 , giving, in most cases,…”
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Configuration of stilbene derivatives by 1H NMR and theoretical calculation of chemical shifts by Rotta, Rodrigo, Cunha Neto, Álvaro, de Lima, Dênis Pires, Beatriz, Adilson, da Silva, Gil Valdo José

“…The direct E/ Z configuration assignment of tri- and tetra-substituted stilbenes (and other analogous olefins) when only one of the isomers is available is a…”
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