Now showing items 1-10 of 181
New tetra-acetylated oligosaccharide diterpene from Cupania vernalis
(Journal of the Brazilian Chemical Society, 2001-06-01) [Artigo]
O diterpeno glicosídico inédito, denominado vernanolídeo, possuindo o esqueleto geranil-geraniol, foi isolado do caule de Cupania vernalis, uma espécie da família Sapindaceae, conhecida popularmente como arco de peneira. ...
Bioactive flavone dimers from Ouratea multiflora (Ochnaceae)
(Revista Brasileira de Farmacognosia, 2007-09-01) [Artigo]
Chromatographic fractionation of the organic extract from leaves of Ouratea multiflora afforded the flavone dimers heveaflavone, amentoflavone-7¢¢,4¢¢¢-dimethyl eter, podocarpusflavone-A and amentoflavone. Their structures ...
Strontium zirconate heterogeneous catalyst for biodiesel production: Synthesis, characterization and catalytic activity evaluation
(Applied Catalysis A: General, 2012-11-28) [Artigo]
Strontium zirconate oxide was synthesized by co-precipitation and the citrate route and was evaluated as a heterogeneous catalyst for biodiesel production. The catalyst samples were characterized by XRD, FTIR, and TG, and ...
Purification of an antibacterial compound from Lantana lilacina
(Revista Brasileira de Farmacognosia, 2008-06-01) [Artigo]
Observou-se, em estudo preliminar, que o extrato metanólico das folhas de L. lilacina, coletadas no município de Lavras (MG, Brasil), apresentava atividade antibacteriana. em decorrência, buscou-se purificar e identificar ...
(1)H NMR Fingerprinting of Brazilian Commercial Gasoline: Pattern-Recognition Analyses for Origin Authentication Purposes
(Energy & Fuels, 2009-08-01) [Artigo]
In (his work, the combination of hydrogen nuclear magnetic resonance ((1)H NMR) fingerprinting of gasoline with pattern-recognition analyses provides an approach to distinguish Brazilian commercial gasoline, processed in ...
Chemical and antifungal investigations of six Lippia species (Verbenaceae) from Brazil
(Planta Medica, 2012-08-01) [Resumo]
Flow-injection spectrophotometric determination of tetracycline and doxycycline in pharmaceutical formulations using chloramine-T as oxidizing agent
(Química Nova, 2009-01-01) [Artigo]
A flow-injection (FI) spectrophotometric procedure is proposed for tetracycline (TC) and doxycycline (DXC) determination in pharmaceuticals. The method is based on the reaction of oxidation of these drugs by chloramine-T ...
Development of a sensitive potentiometric sensor for determination of fumaric acid in powdered food products
(Food Chemistry, 2012-09-01) [Artigo]
A new potentiometric sensor, namely, Pt vertical bar Hg vertical bar Hg-2 FUM vertical bar graphite, where FUM represents the fumarate ion was developed for the measurement of fumaric acid in foods. The characteristics, ...
Antiprotozoal Sesquiterpene Pyridine Alkaloids from Maytenus ilicifolia
(Journal of Natural Products, 2012-05-01) [Artigo]
As part of a bioprospecting program aimed at the discovery of antiprotozoal agents from the Brazilian flora, two new sesquiterpene pyridine alkaloids, ilicifoliunines A (1) and B (2), along with the known alkaloids ...
Xylarenones C-E from an Endophytic Fungus Isolated from Alibertia macrophylla
(Journal of Natural Products, 2011-06-01) [Artigo]
Xylarenones C-E (2-4), three new eremophilane sesquiterpenes, have been isolated from solid substrate cultures of a Camarops-like endophytic fungus isolated from Alibertia macrophylla. The structures were elucidated by ...