Search Results - "Ferraz, Helena M. C"

(+)- and (−)-Mutisianthol: First Total Synthesis, Absolute Configuration, and Antitumor Activity by Bianco, Graziela G., Ferraz, Helena M. C., Costa, Arinice M., Costa-Lotufo, Letícia V., Pessoa, Cláudia, de Moraes, Manoel O., Schrems, Marcus G., Pfaltz, Andreas, Silva, Luiz F.

“…The first synthesis of the natural product (+)-mutisianthol was accomplished in 11 steps and in 21% overall yield from 2-methylanisole. The synthesis of its…”
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A Ring Contraction Strategy toward a Diastereoselective Total Synthesis of (+)-Bakkenolide A by Carneiro, Vânia M. T, Ferraz, Helena M. C, Vieira, Tiago O, Ishikawa, Eloisa E, Silva, Luiz F

“…A diastereoselective route to (+)-bakkenolide A is presented from the readily available optically active Wieland−Miescher ketone. This novel synthesis of this…”
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Bicyclic β-Hydroxytetrahydrofurans as Precursors of Medium Ring Keto-Lactones by Ferraz, Helena M. C, Longo, Luiz S

“…The reaction of a series of cis-fused bicyclic β-hydroxytetrahydrofurans with ruthenium tetraoxide, generated in situ from ruthenium trichloride and sodium…”
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Efficient Entry into Medium-Ring Keto-Lactones. The Ruthenium Tetraoxide-Promoted Oxidative Cleavage of β-Hydroxyethers by Ferraz, Helena M. C, Longo, Luiz S

“…A new use of ruthenium tetraoxide is reported. The catalytic oxidative cleavage of hexahydro-benzofuran-3a-ols led to nine-membered ring keto-lactones in…”
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Unexpected Synthesis of Conformationally Restricted Analogues of γ-Amino Butyric Acid (GABA):  Mechanism Elucidation by Electrospray Ionization Mass Spectrometry by Ferraz, Helena M. C, Pereira, Fernando L. C, Gonçalo, Érika R. S, Santos, Leonardo S, Eberlin, Marcos N

“…From previous results with lower homologues, dehydroiodination of the three alkenyl-β-enamino esters 3a−c was expected to provide six-membered N-heterocyclic…”
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Synthesis of Cyclic Enol Ethers from Alkenyl-β-dicarbonyl Compounds by Ferraz, Helena M. C, Sano, Myrian K, Nunes, Marta R. S, Bianco, Graziela G

“…In this work we describe the cyclofunctionalization of eleven differently substituted alkenyl-β-dicarbonyl compounds, employing three electrophilic reagents,…”
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Thallium Trinitrate Mediated Oxidation of 3-Alkenols:  Ring Contraction vs Cyclization by Ferraz, Helena M. C, Longo, Luiz S, Zukerman-Schpector, Julio

“…The reaction of a series of six-membered ring 3-alkenols with thallium trinitrate (TTN) in three different experimental conditions was studied. Either…”
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Natural occurrence, biological activities and synthesis of eight-, nine-, and eleven-membered ring lactones by Ferraz, Helena M. C., Bombonato, Fernanda I., Sano, Myrian K., Longo Jr, Luiz S.

“…The natural occurrence, biological activities and synthetic approaches to natural eight-, nine-, and eleven-membered lactones is reviewed. These medium ring…”
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Bioreduction of substituted a-tetralones promoted by Daucus carota root by Ferraz, Helena M. C., Bianco, Graziela G., Bombonato, Fernanda I., Andrade, Leandro H., Porto, André L. M.

“…The bioreduction of a series of substituted a-tetralones, carried out using Daucus carota root (carrot), afforded the corresponding homochiral a-tetralols in…”
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Rearrangement of beta,gamma-unsaturated esters with thallium trinitrate: synthesis of indans bearing a beta-keto ester moiety by Silva Jr, Luiz F., Pedrozo, Eliane C., Ferraz, Helena M. C.

“…The rearrangement of beta,gamma-unsaturated esters, such as 2-(3,4-dihydronaphthalen-1-yl)-propionic acid ethyl ester, with thallium trinitrate (TTN) in acetic…”
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A New and Efficient Approach to Cyclic .beta.-Enamino Esters and .beta.-Enamino Ketones by Iodine-Promoted Cyclization by Ferraz, Helena M. C, de Oliveira, Eliseu O, Payret-Arrua, M. Elena, Brandt, Carlos A

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Síntese de enaminonas by Ferraz, Helena M. C, Pereira, Fernando L. C.

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A Short Route to (−)-Mintlactone by Thallium(III)-Mediated Cyclization of (−)-Isopulegol by Ferraz, Helena M. C, Grazini, Mônica V. A, Ribeiro, Carlos M. R, Brocksom, Ursula, Brocksom, Timothy J

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Preparações e aplicações sintéticas recentes de enaminonas by Ferraz, Helena M. C., Gonçalo, Erika R. S.

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Thallium Trinitrate Mediated Ring Contraction of trans-2-Decalones:  An Alternative Entry to the Hydrindane System by Ferraz, Helena M. C, Silva, Luiz F

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Thallium trinitrate mediated ring contraction of cis-2-decalones by Ferraz, Helena M. C., Silva Jr, Luiz F.

“…The reaction of some cis-2-decalones with TTN in CH2Cl2 at room temperature was investigated. The ring contraction reactions occurred in good yields, however…”
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Reações de contração de anel promovidas por sais de tálio(III) by Ferraz, Helena M. C., Silva Jr.<A NAME="top", Luiz F.

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Estratégias sintéticas para o ácido nonático by Ferraz, Helena M. C., Payret-Arrúa, M. Elena

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Total syntheses of the sesquiterpenes β-corymbolol and corymbolone by Ferraz, Helena M.C., Souza, Antonio J.C., Tenius, Beatriz S.M., Bianco, Graziela G.

“…The first total synthesis of racemic corymbolone, an eudesmane sesquiterpene isolated from Cyperus species used in traditional medicine to treat many diseases,…”
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Enzymatic resolution of α-tetralols by CALB-catalyzed acetylation by Ferraz, Helena M.C., Bianco, Graziela G., Teixeira, Carla C., Andrade, Leandro H., Porto, André L.M.

“…A series of homochiral α-tetralols, as well as their respective acetates, has been obtained by esterification of racemic tetralols, using Candida antarctica…”
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