Now showing items 21-30 of 895
Antifungal iridoids from the stems of Tocoyena formosa
(Journal of the Brazilian Chemical Society, 1996-07-01) [Artigo]
A new antifungal iridoid compound, together with three active known iridoids, galioside, galioside aglucone, and apodanthoside, as well as 3-O-beta-D-glucopyranosyl-28-O-beta-D-glucopyranosyl quinovic acid and quercetin- ...
Electrospray ionization mass spectrometry screening of piperidine alkaloids from Senna spectabilis (Fabaceae) extracts: Fast identification of new constituents and co-metabolites
(Journal of the Brazilian Chemical Society, 2005-11-01) [Artigo]
The fragmentation pattern of a homologous series of piperidine alkaloids isolated from S. spectabilis was investigated using electrospray ionization tandem mass spectrometry (ESI-MS/MS). The ESI-MS and ESI-MS/MS analyses ...
Isolation, optimization of production and structure-activity relationship studies of monocillin I, the cytotoxic constituent of Paraphaeosphaeria quadriseptata
(Journal of Antibiotics, 2004-08-01) [Artigo]
Selective DMSO-induced conformational changes in proteins from Raman optical activity
(Physical Chemistry Chemical Physics, 2013-01-01) [Artigo]
The function of a protein is determined by its structure, which is intrinsically related to its solvent environment. Based on this paradigm, there has been a great deal of interest in the role that nonaqueous solvents play ...
Clerodane diterpenes from Aristolochia species
(Phytochemistry, 1987-12-01) [Artigo]
The investigation of Aristolochia brasiliensis and A. esperanzae afforded 12 clerodane derivatives, including the following six novel ones: rel (5S, 8R, 9S, 10R)-2-oxo-ent-3-cleroden-15-oic acid, rel (5S, 8R, 9S, ...
(Acta Crystallographica Section E: Structure Reports Online, 2008-06-01) [Artigo]
In the two, almost identical, molecules in the asymmetric unit of the title compound [ systematic name: (E)-3-methyl-5-(1,2,4a, 5-tetramethyl-1,2,3,4,4a,7,8,8a-octahydronaphthalen-1yl) pent-2-enoic acid], C20H32O2, the ...
Clerodane diterpenes from leaves of Casearia sylvestris swartz
(Química Nova, 2007-09-01) [Artigo]
Ethanolic extracts of the leaves of Casearia sylvestris yielded a novel clerodane diterpene, 15-hydroxy-3-cleroden-2-one, together with the known diterpenes (-)-hardwickiic acid, reported for the first time from this ...
Cryptomoschatone D2 from Cryptocarya mandioccana: cytotoxicity against human cervical carcinoma cell lines
(Revista de Ciências Farmacêuticas Básica e Aplicada, 2009) [Artigo]
Among the substances isolated from Cryptocarya sp, some styrylpyrones, such as goniothalamin, demonstrate antiproliferative activity in a broad range of human cell lines. In the present study, we assessed the cytotoxicity ...
Essential oils from leaves of cryptocarya spp from the atlantic rain forest
(Química Nova, 2008-01-01) [Artigo]
The essential oils from leaves of four Cryptocarya spp endemic in the Brazilian Atlantic rain forest were obtained by hydrodistillation and shown by GC-MS analysis to contain mono and sesquiterpenes. The major components ...
Composition and antifungal activity of essential oils from Piper aduncum, Piper arboreum and Piper tuberculatum
(Química Nova, 2006-05-01) [Artigo]
The composition of essential oils from leaves, stems and fruits of Piper aduncum, P arboreum and P. tuberculatum was examined by means of GC-MS and alltifungal assay. There was a predominance of monoterpenes in P aduncum ...