Pyrones
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. Síntese e atividade biológica de pironas e piridinonas derivadas do ácido desidroacético / Synthesis and biological activities of pyrones and pyridinones derived from dehydroacetic acid
Um grande número de compostos contendo o anel piran-2-ona ou piridin-2-ona apresenta atividade antibacteriana, antifúngica, antimalárica, cardiotônica, analgésica, anti-inflamatória, citotóxica, neurotóxica, inseticida, anti-HIV, antioxidante e fitotóxica. O presente trabalho teve como objetivos sintetizar enaminopiranonas contendo o anel piran-2-on
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 31/08/2010
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2. CHEMISTRY OF Acosmium dasycarpum: IDENTIFICATION OF QUINOLIZIDINE ALKALOIDS BY GC-MS / CHEMISTRY OF Acosmium dasycarpum: IDENTIFICATION OF QUINOLIZIDINE ALKALOIDS BY GC-MS / Química de Acosmium dasycarpum : identificação de alcalóides quinolizidínicos por CG-EM / Química de Acosmium dasycarpum : identificação de alcalóides quinolizidínicos por CG-EM
This work reports the identification of quinolizidíne alkaloids (QA) and other non-alkaloidal secondary metabolites found in plants, and a discussion on the likely biosynthetic pathway of quinolizidine alkaloids. Phytochemical study of A. dasycarpum resulted in the isolation of 26 substances, 9 of them quinolizidine alkaloids: homo-6-epipodopetaline, acosmi
Publicado em: 2009
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3. Study of vasorelaxant effect of one pyrone obtained from Aniba panurensis in isolated superior mesenteric artery rat / Estudo do efeito vasorelaxante de uma pirona obtida de Aniba panurensis em artÃria mesentÃrica superior isolada de rato
6 - [(E) â styryl] â pyron â 2 - one (pyrone-198) is a natural styrylpyrone isolated from the ethanolic extract of the green fruits of Aniba panurensis (Lauraceae). The pyrones demonstrate a whole spectrum of bioactivity and have been shown to be antifungal, antibiotic, cytotoxic and phytotoxic. The aim of this study is to investigate the effects of this
Publicado em: 2007
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4. Lucibufagins: Defensive steroids from the fireflies Photinus ignitus and P. marginellus (Coleoptera: Lampyridae)*
Feeding tests with thrushes (Hylocichla spp.) led to the isolation of three novel steroid pyrones from fireflies (Photinus ignitus and P. marginellus) responsible, in part at least, for the unpalatability of these insects to the birds. The term lucibufagin is coined for these steroidal pyrones. The closest known relatives of lucibufagins are the familiar car
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5. Sex pheromone for the brownbanded cockroach is an unusual dialkyl-substituted alpha-pyrone.
Female brownbanded cockroaches, Supella longipalpa, emit a sex pheromone that attracts males from a distance. This pheromone was isolated and identified as 5-(2,4-dimethylheptanyl)-3-methyl-2H-pyran-2-one (which we refer to as supellapyrone), and its structure was confirmed by synthesis. A racemic blend of the synthetic compound elicited behavioral and elect
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6. Firefly “femmes fatales” acquire defensive steroids (lucibufagins) from their firefly prey
Female fireflies of the genus Photuris, the so-called firefly “femmes fatales,” prey on male fireflies of the genus Photinus. The females are able to entrap the males by faking the flash signal characteristics of the Photinus female. We found that by feeding on Photinus males, Photuris females gain more than nutrients. They also acquire defensive s
The National Academy of Sciences of the USA.
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7. Antiviral activity of the dihydropyrone PNU-140690, a new nonpeptidic human immunodeficiency virus protease inhibitor.
PNU-140690 is a member of a new class of nonpeptidic human immunodeficiency virus (HIV) protease inhibitors (sulfonamide-containing 5,6-dihydro-4-hydroxy-2-pyrones) discovered by structure-based design. PNU-140690 has excellent potency against a variety of HIV type 1 (HIV-1) laboratory strains and clinical isolates, including those resistant to the reverse t
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8. Naphtho-gamma-pyrone production by Aspergillus niger isolated from stored cottonseed.
Aspergillus niger was found to be the predominant fungal contaminant of stored cottonseed. Seven strains were isolated and grown on rice. The hexane-insoluble material from methylene chloride extracts of 2-week-old cultures contained components toxic to mice. Based on high-pressure thin-layer and liquid chromatographic analyses, the major components in the m
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9. Acetic Acid Bacterial Biota of the Pink Sugar Cane Mealybug, Saccharococcus sacchari, and Its Environs
Saccharococcus sacchari is the primary colonizer of the developing “sterile” tissue between the leaf sheath and stem of sugar cane. The honeydew secreted by the mealybugs is acidic (about pH 3) and supports an atypical epiphytic microbiota dominated by acetobacter-like bacteria and acidophilic yeast species. However, Erwinia and Leuconostoc species predo
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10. Novel Ring Cleavage Products in the Biotransformation of Biphenyl by the Yeast Trichosporon mucoides
The yeast Trichosporon mucoides, grown on either glucose or phenol, was able to transform biphenyl into a variety of mono-, di-, and trihydroxylated derivatives hydroxylated on one or both aromatic rings. While some of these products accumulated in the supernatant as dead end products, the ortho-substituted dihydroxylated biphenyls were substrates for furthe
American Society for Microbiology.