Search Results - "Geonir M. Siqueira"

Synthesis and biological evaluation of benzothiazin-4-ones: a possible new class of acetylcholinesterase inhibitors by Berwaldt, Gabriele A., Gouvêa, Daniela P., da Silva, Daniel S., das Neves, Adriana M., Soares, Mayara S. P., Azambuja, Juliana H., Siqueira, Geonir M., Spanevello, Roselia M., Cunico, Wilson

“…A series of nineteen benzothiazin-4-ones from N-(3-aminopropyl) piperidine, 4-(2-aminoethyl)morpholine or 1-(2-aminoethyl)piperidine, aliphatic or aromatic…”
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Sonochemistry: A good, fast and clean method to promote the synthesis of 5-arylidene-2,4-thiazolidinediones by Drawanz, Bruna B., Ribeiro, Camila S., Masteloto, Hellen G., Neuenfeldt, Patrícia D., Pereira, Claudio M.P., Siqueira, Geonir M., Cunico, Wilson

“…•Sixteen 5-arylidene-2,4-thiazolidinediones were synthesized by ultrasound irradiation.•The desire products were obtained in short reaction times…”
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Antifungal activity of 3-(heteroaryl-2-ylmethyl)thiazolidinone derivatives by Marques, Gabriela H, Kunzler, Alice, Bareño, Valéria D O, Drawanz, Bruna B, Mastelloto, Hellen G, Leite, Fabio R M, Nascimento, Gustavo G, Nascente, Patrícia S, Siqueira, Geonir M, Cunico, Wilson

“…Thiazolidinones, synthesized from multicomponent reactions of 2-heteroarylmethylamine, arenealdehydes and mercaptoacetic acid, have been tested against six…”
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7-chloroquinolin-4-yl arylhydrazone derivatives: synthesis and antifungal activity by Duval, Auri R, Carvalho, Pedro H, Soares, Maieli C, Gouvêa, Daniela P, Siqueira, Geonir M, Lund, Rafael G, Cunico, Wilson

“…Fifteen 7-chloro-4-arylhydrazonequinolines have been evaluated for their in vitro antifungal activity against eight oral fungi: Candida albicans, C…”
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Ultrasonics promoted synthesis of thiazolidinones from 2-aminopyridine and 2-picolilamine by Gouvêa, Daniela P., Bareño, Valéria D.O., Bosenbecker, Juliano, Drawanz, Bruna B., Neuenfeldt, Patrícia D., Siqueira, Geonir M., Cunico, Wilson

“…► Efficient ultrasound irradiation to obtain thiazolidinones. ► The less reactive 2-aminopyridine needs a Lewis acid catalysis to afford the products. ► The…”
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Ultrasound-promoted synthesis of 3-trichloromethyl-5-alkyl(aryl)-1,2,4-oxadiazoles by Bretanha, Lizandra C., Teixeira, Vinicius E., Ritter, Marina, Siqueira, Geonir M., Cunico, Wilson, Pereira, Claudio M.P., Freitag, Rogério A.

“…► Ultrasound increase yields. ► Better reaction times than conventional method. ► Improved synthesis of 1,2,4-oxadizoles. The alternative synthesis of 12…”
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Ultrasound promoted synthesis of thioesters from 2-mercaptobenzoxa(thia)zoles by Duarte, Anaí, Cunico, Wilson, Pereira, Claudio M.P., Flores, Alex F.C., Freitag, Rogério A., Siqueira, Geonir M.

“…An ultrasound-enhanced method has been developed for the synthesis of a variety of thioesters from benzoyl chlorides and 2-mercaptobenzoxa(thia)zoles. Applying…”
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The antinociceptive evaluation of 2,3-substituted-1,3-thiazolidin-4-ones through thermal stimulation in mice by Neves, Arthur H. S., da Silva, Daniel S., Siqueira, Geonir M., Gamaro, Giovana D., Cunico, Wilson, da Silva, Adriana L.

“…The present study assessed the 2,3-substituted-1,3-thiazolidin-4-ones antinociceptive potential looking at the acute nociception model induced by thermal…”
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Efficient Synthesis and Antioxidant Evaluation of 2-Aryl-3-(Pyrimidin-2-yl)-Thiazolidinones by Campos Júnior, José C., Gouvêa, Daniela P., Ribeiro, Camila da S., Dutra, Filipe S. P., Stefanello, Francieli M., Pereira, Claudio M. P., Cunico, Wilson, Siqueira, Geonir M.

“…ABSTRACT In the present study, we reported the efficient synthesis of 11 3‐(pyrimidin‐2‐yl)‐thiazolidinones in good yields using molecular sieve as the…”
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Regiospecific synthesis of 1,2-bis(azolyl)ethanes by Martins, Marcos A. P., Cunico, Wilson, Siqueira, Geonir M., Leidens, Victor L., Zanatta, Nilo, Bonacorso, Helio G., Flores, Alex F. C.

“…The synthesis of 1,2-bis(5'-trihalomethylisoxazol-3'-yl)ethanes (3-6) and 1,2-bis(5'-trihalomethylpyrazol-3'-yl)ethanes (7-10) from the cyclocondensation of…”
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Efficient solvent-free synthesis of thiazolidin-4-ones from phenylhydrazine and 2,4-dinitrophenylhydrazine by Neuenfeldt, Patrícia D., Drawanz, Bruna B., Siqueira, Geonir M., Gomes, Claudia R.B., Wardell, Solange M.S.V., Flores, Alex F.C., Cunico, Wilson

“…An efficient solvent-free synthesis of thiazolidinones from phenylhydrazine and 2,4-dinitrophenylhydrazine has been described. An efficient solvent-free…”
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3,4-(Methylenedioxy)aniline as precursor to the synthesis of thiazolidin-4-ones by Masteloto, Hellen G., Drawanz, Bruna B., Berwaldt, Gabriele A., Neuenfeldt, Patricia D., Siqueira, Geonir M., Cunico, Wilson

“…New 2-aryl-3-(benzo[ d ][1,3]dioxol-5-yl)thiazolidin-4-ones were easily synthesized by one-pot reaction of (3,4-methylenedioxy)aniline, arenaldehydes (or…”
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Aplicação de α-oxoceteno ditiocetais em síntese orgânica by Siqueira, Geonir M., Neuenfeldt, Patrícia D., Duarte, Anaí, Bretanha, Lizandra C., Freitag, Rogério A., Cunico, Wilson

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Aplicação de α-oxoceteno ditiocetais em síntese orgânica Reactivity of α-oxoketene dithiocetals in organic synthesis by Geonir M. Siqueira, Patrícia D. Neuenfeldt, Anaí Duarte, Lizandra C. Bretanha, Rogério A. Freitag, Wilson Cunico

“…The synthesis and reactivity of α-oxoketenes dithioacetals (S,S-acetals), general structure [(R¹C=OC(R²)=C(SR³)(SR4)], are reported. We also showed the…”
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Synthesis and Structural Analysis of Trichloroacetamidoxime by Bretanha, Lizandra C., Freitag, Rogério A., Siqueira, Geonir M., Ritter, Marina, Campos, Patrick T., Martins, Marcos A. P.

“…The trichloroacetoamidoxime was synthesized following the principles of green chemistry in excellent yield (90 %). This compound crystallizes in the…”
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The first synthesis of β-phenylchalcogeno-α,β-unsaturated esters via hydrochalcogenation of acetylenes using microwave and solvent-free conditions by Perin, Gelson, Jacob, Raquel G., de Azambuja, Francisco, Botteselle, Giancarlo V., Siqueira, Geonir M., Freitag, Rogério A., Lenardão, Eder J.

“…[Display omitted] A simple, clean, and efficient solvent-free protocol was developed for hydrochalcogenation of methyl propiolate derivatives with…”
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Preparation of trichloroacetoamidoxime in aqueous media and application in one pot synthesis of 1,2,4-oxadiazoles by Bretanha, Lizandra C., Venzke, Dalila, Campos, Patrick T., Duarte, Anaí, Martins, Marcos A. P., Siqueira, Geonir M., Freitag, Rogério A.

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Regiospecific acylation of acetals. A convenient method to obtain β-methoxyvinyl trichloromethyl ketones by Martins, Marcos A.P., Bastos, Giovani P., Bonacorso, Helio G., Zanatta, Nilo, Flores, Alex F.C., Siqueira, Geonir M.

“…The regiochemistry of the acylation of enol ethers, generated in situ, from acetals of unsymmetrical ketones is reported. These results demonstrate a…”
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Haloacetylated enol ethers. 7 . Synthesis of 3-aryl-5-trihalomethylisoxazoles and 3-aryl-5-hydroxy-5-trihalomethyl-4,5-dihydroisoxazoles by Martins, Marcos A. P., Siqueira, Geonir M., Bastos, Giovani P., Bonacorso, Helio G., Zanatta, Nilo

“…β‐Aryl‐β‐methoxyvinyl trihalomethyl ketones 1a‐g, 2a‐g [aryl = p‐YC6H4 where Y= H, Me, OMe, F, Cl, Br, NO2] are cyclocondensed with hydroxylamine hydrochloride…”
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17O NMR chemical shifts: a simple and useful rule for substituent additivity on oxygen atoms with a coordination number of two by Martins, Marcos A. P., Zanatta, Nilo, Bonacorso, Helio G., Siqueira, Geonir M., Flores, Alex F. C.

“…The 17O chemical shifts of simple aliphatic ethers were studied, and the additivity substituent increments for carbon atoms in the alkyl groups were…”
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