Bis Lactones
Mostrando 1-9 de 9 artigos, teses e dissertações.
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1. Synthetic Studies toward (−)-Cleistenolide: Highly Stereoselective Synthesis of New γ-Lactone Subunits
This study describes the stereoselective synthesis of two new γ-lactones in 6 and 3 steps and 19 and 32% yield, respectively, directed toward the total synthesis of the natural product (−)-cleistenolide. The starting material was an enantiomerically pure diacetonide diol, derived from d-mannitol with the required stereocenters for (−)-cleistenolide synt
J. Braz. Chem. Soc.. Publicado em: 2021-04
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2. Synthesis and antifungal activity of halogenated aromatic bis-γ-lactones analogous to avenaciolide
Here we describe the total syntheses and characterization by elemental analyses, infrared and NMR spectroscopy of three new compounds analogous to avenaciolide, a bis-γ-lactone isolated from Aspergillus avenaceus that possesses antifungal activity, where the octyl group of the natural product was replaced by aromatic groups containing chlorine and fluorine
Química Nova. Publicado em: 2012
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3. Síntese e atividade antifúngica do avenaciolídeo e de bis-γ-lactonas análogas com cadeias laterais alifáticas / Synthesis and antifungal activity of avenaciolide and bis-γ-lactonas with alifhatic lateral chains
Avenaciolide is a natural product with an α,β-unsaturated bis-γ-lactone structure and a linear lateral chain with eight carbon atoms. Using the Chiral pool strategy, two avenaciolide analogs were prepared from D-glucose, containing linear lateral chains of 11 and 17 carbon atoms, [A] and [B], respectively. The different lateral chains were add
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/02/2010
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4. Synthesis and study of the antifungal activity of avenaciolide and new bis-lactones analogues / Síntese e estudo da atividade fungicida do avenaciolídeo e de novas bis-lactonas análogas
A rota sintética utilizada neste trabalho teve como material de partida um carboidrato, a D-glicose. Os carboidratos são muito úteis como precurssores sintéticos, principalmente por possuírem pureza enantiomérica e a presença de muitos grupos funcionais. A partir da D-glicose, várias reações foram realizadas, obtendo-se um total de 30 compostos, se
Publicado em: 2008
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5. Synthesis and antifungal activity of new bis-gamma-lactones analogous to avenaciolide
Com o objetivo de avaliar o potencial agroquímico de uma série de compostos com atividade fungicida, foram preparadas e caracterizadas por análises elementares e espectroscopias no infravermelho e de RMN, três novas bis-gama-lactonas análogas ao avenaciolídeo, onde o grupo octila presente nesse produto natural foi substituído por grupos heptila, hexil
Journal of the Brazilian Chemical Society. Publicado em: 2007-04
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6. Estudos sobre a síntese enantiosseletiva de lignano-lactonas naturais / Estudies of enantioselective synthesis of natural lignan-lactones
As lignanas naturais possuem vários tipos de estruturas que exibem uma vasta gama de atividades biológicas. As lignano-lactonas naturais, tais como a arctigenina (1) e os derivados da podofilotoxina (2), representadas nas estruturas abaixo, são conhecidas por apresentarem atividades citotóxicas e, há várias décadas, vêm despertando enorme interesse e
Publicado em: 2007
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7. Constituintes quimicos de cinco especies de Echinodorus e avaliação do beta-pineno como substrato para obtenção de quirons mais elaborados
The present thesis has been divided into two sections The first part concerns the isolation and identification of the secondary metabolites of the leaves and pecioles of Echinodorus grandiflorus from Curitiba-PR. Conventional phytochemical analysis resulted in the identification of 11 compounds : phytol (8), hardwickic acid, methyl ester (14a), echinoic acid
Publicado em: 2000
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8. Zr[bis(salicylidene)ethylenediaminato]-mediated Baeyer–Villiger oxidation: Stereospecific synthesis of abnormal and normal lactones
Baeyer–Villiger oxidation of racemic bicyclic cyclobutanones with Zr[bis(salicylidene)ethylenediaminato] (salen) complex 1 as catalyst in the presence of a urea-hydrogen peroxide adduct was found to proceed enantiospecifically. The enantiotopos selection in the oxidation was governed primarily by the Zr(salen) catalyst, although migratory aptitude (methine
National Academy of Sciences.
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9. Inhibition of glutathione synthesis augments lysis of murine tumor cells by sulfhydryl-reactive antineoplastics.
GSH plays an important role in cellular defense against a wide variety of toxic electrophiles via the formation of thioether conjugates. We studied the role of GSH in murine tumor cell defense against a novel class of sulfhydryl-reactive antineoplastics, the sesquiterpene lactones (SL). Incubation of P815 mastocytoma cells with any of the four SL tested (ver