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Marc P. Maillard Maria-Carmen Recio-Iglesias Mahamane Saadou Helen Stoeckli-Evans Kurt Hostettmann 《Helvetica chimica acta》1991,74(4):791-799
As the root bark CH2Cl2 extract of Bauhinia rufescens showed antifungal activity in a bioassay with the plant pathogenic fungus Cladosporium cucumerinum, a phytochemical investigation was undertaken on material collected in Niger. Activity-guided fractionation of this extract, using different preparative chromatographic methods, allowed the isolation of the four new antifungal tetracyclic compounds 1 – 4 . Their structures were established by 1H- and 13C-NMR data, and single-crystal X-ray analyses were used to confirm the structures of 1 and 3 . The isolated compounds seem to be biogenetically related to a stilbene. 相似文献
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Maria-Teresa Doménech-Carbó Antonio Doménech-Carbó Laura Osete-Cortina Maria-Carmen Saurí-Peris 《Mikrochimica acta》2006,154(1-2):123-142
The combined use of scanning electron microscopy/energy dispersive X-ray microanalysis (SEM/EDX) and square wave voltammetry
(SQWV), is used for studying the corrosion processes that have taken place in buried glass from different archaeological sites
in the Valencian Region (Spain). The procedures permit a parallel investigation of morphology and chemical composition. Determination
of the chemical composition of the glasses and their alteration crust and identification of the elements responsible for the
colour has been also carried out using energy dispersive X-ray microanalysis. The electrochemical response of samples attached
to paraffin-impregnated graphite electrodes reveals the presence of different iron and manganese oxide species in the browning
areas of the corroded glass. Image analysis applied to microphotographs obtained by means of SEM led to the determination
of morphological parameters concerning the corrosion phenomena occurring on the surface of the fragments such as thickness
of the corrosion layer and its laminated structure. Additionally, measurement of the thickness of the film of polymer used
as coating in the consolidation treatments has been carried out using cryo-scanning electron microscopy (cryo-SEM) combined
with image analysis. 相似文献
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Bermejo A Figadere B Zafra-Polo MC Barrachina I Estornell E Cortes D 《Natural product reports》2005,22(2):269-303
The aim of the present review is to summarise the knowledge about newly isolated acetogenins (ACGs) in the last six years. It will also report the total syntheses that have allowed either the confirmation or the revision of some structures, together with the biological activities and mechanism of action of such interesting natural products. In fact, of the 417 isolated compounds reviewed, over 176 have been added during the period from 1998 to 2004. 相似文献
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