O-heterocyclic embeurekols from Embellisia eureka, an endophyte of Cladanthus arabicus
Weaam Ebrahim1, Amal H Aly, Attila Mándi
1Institut für Pharmazeutische Biologie und Biotechnologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, Geb. 26.23, 40225 Düsseldorf, Germany.
Abstract:
Three new polyketides ((-)-1, (+)-1, and 2) were isolated from the EtOAc extract of the fungus Embellisia eureka, an endophyte of the Moroccan plant Cladanthus arabicus (Asteraceae). The structures of these new compounds were determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configurations of (-)-1, (+)-1, and 2 were determined by TDDFT ECD calculations of solution conformers, online HPLC-ECD analysis, and the modified Mosher method.
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