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1.
Phytochemistry ; 67(17): 1943-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16876210

RESUMO

Six species of Portuguese Ulex L. in a total of nineteen populations were studied by GC-EIMS as to their content in quinolizidine alkaloids. Sparteine, beta-isosparteine, jussiaeiine A, N-methylcytisine, cytisine, 5,6-dehydrolupanine, rhombifoline, lupanine, jussiaeiine B, N-formylcytisine, N-acetylcytisine, anagyrine, jussiaeiine C, jussiaeiine D, pohakuline, baptifoline, and epibaptifoline were detected. Analysis of the chromatograms showed that the chemical profile of all species was mainly composed of N-methylcytisine, cytisine, anagyrine, and jussiaeiines A, B, C and D. Therefore a quantification study of these alkaloids in all the populations studied was done by GC. These data were then submitted to cluster analysis and principal component analysis, which allowed the definition of five chemotypes and the recognition of hybrids. N-methylcytisine, cytisine, and jussiaeiines A, C and D are recognized as markers of this genus in Portugal.


Assuntos
Alcaloides/química , Quinolizinas/química , Ulex/química , Ulex/classificação , Cromatografia Gasosa/métodos , Análise por Conglomerados , Estrutura Molecular , Portugal , Análise de Componente Principal , Espectrometria de Massas por Ionização por Electrospray/métodos
2.
Phytochem Anal ; 16(4): 264-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16042152

RESUMO

Gas chromatography coupled with mass spectrometry has been used to analyse the alkaloids present in the aerial parts of Genista tenera. Anagyrine, cytisine, N-formylcytisine, N-methylcytisine and lupanine were the major compounds, the last two alkaloids being known for their hypoglycaemic activity. Dehydrocytisine, 5,6-dehydrolupanine, rhombifoline, aphylline and thermopsine were the minor alkaloids. The characterisation of the constituents was based on comparison of their Kovats retention indexes and electron impact-mass spectrometric data recorded on-line with those of reference compounds and literature data.


Assuntos
Alcaloides/isolamento & purificação , Fabaceae/química , Quinolizinas/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Hipoglicemiantes/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Portugal
3.
Z Naturforsch C J Biosci ; 58(11-12): 776-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14713148

RESUMO

The alkaloid composition of the aerial parts of two taxa of Teline maderensis was studied by capillary GLC and GLC-MS. N-Methylcytisine was the major alkaloid found in both plants. Contents of cytisine and lupanine were higher in T. maderensis var. paivae while anagyrine content was more pronounced in T. maderensis var. maderensis. The alkaloids dehydrocytisine, N-acetylcytisine and epibaptifoline appeared only in T. maderensis var. maderensis and N-formylcytisine was identified as a minor constituent in T. maderensis var. paivae, and detected only in trace amounts in the other variety of the plant.


Assuntos
Alcaloides/química , Fabaceae/química , Quinolinas/química , Alcaloides/isolamento & purificação , Cromatografia Gasosa , Fabaceae/classificação , Quinolinas/isolamento & purificação
4.
Z Naturforsch C J Biosci ; 57(1-2): 63-71, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11926545

RESUMO

The occurrence of thiophenic compounds in diverse plant organs and in in vitro root-, callus- and cell suspension cultures of Tagetes patula cv. Carmen was investigated using capillary GLC and GLC-MS. The separation of thiophenes by capillary GLC and the group specific MS fragmentation with the typical sulfur isotope peaks allowed the unequivocal assignment of individual thiophenes in complex mixtures, even when occurring in traces and in the presence of different geometrical isomers. The extracts of Tagetes patula cv. Carmen contained the following 8 thiophene compounds: 5-(3-buten-1-ynyl)-2,2'-bithienyl (BBT), 5'-methyl-5-(3-buten-1-ynyl)-2,2'-bithienyl (MeBBT), 5-(1-pentynyl)-2,2'-bithienyl (PBT), 5-(4-hydroxy-1-butynyl)-2,2'-bithienyl (BBTOH), 2,2',5,2"-terthienyl (alpha-T), 5-(4-acetoxy-1-butynyl)-2,2'-bithienyl (BBTOAc), 5-methylaceto-5'-(3-buten-1-ynyl)-2,2'-bithienyl (AcOCH2BBT), and 5-(3,4-diacetoxy-1-butynyl)-2,2'-bithienyl (BBT(OAc)2). The most complex thiophene profile, including the less common PBT was detected in aerial parts of freshly harvested plant material. Under in vitro conditions only the root cultures, but not callus or cell suspension cultures produced substantial amounts of irregular thiophenes confirming that roots are the main site of thiophene biosynthesis.


Assuntos
Asteraceae/química , Tiofenos/química , Asteraceae/citologia , Asteraceae/fisiologia , Células Cultivadas , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Modelos Moleculares , Conformação Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/citologia , Tiofenos/isolamento & purificação , Tiofenos/metabolismo
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