Marion Dörr
Technische Universität Darmstadt
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Publication
Featured researches published by Marion Dörr.
Zeitschrift für Naturforschung C | 2003
Eckhard Wollenweber; Marion Dörr; Diego Rivera; James N. Roitman
Abstract The Mediterranean Ononis species, O. fruticosa, O. natrix subsp. ramosissima and O. tridentata, have been analyzed for their exudate flavonoids. More than 20 flavonoid aglycones were identified, some of which are rather rare natural compounds. One of them, namely hypolaetin- 8,3′,4′-trimethyl ether, had been found only once before. The results are presented in a table along with literature data, and the chemotaxonomic impact of the flavonoid patterns is discussed.
Phytochemistry | 2003
Eckhard Wollenweber; Jan F. Stevens; Marion Dörr; Andrew C. Rozefelds
Forty-two flavonoids and a stilbene (pinosylvin) were identified in the leaf exudates of 11 temperate species of Nothofagus from South America, Australia and New Zealand. The flavonoid profiles demonstrate significant taxonomic value at the subgeneric level. Most species of subgenus Fuscospora are characterized by the presence of pinosylvin, galangin and galangin methyl ethers. Kaempferol-type flavonols are abundant in subgenus Lophozonia while these flavonols are largely absent from species of subgenus Fuscospora. The flavonoid patterns are largely in agreement with a recent subgeneric classification of Nothofagus.
Phytochemistry | 1995
Eckhard Wollenweber; Marion Dörr; Abdolhossein Rustiyan
Abstract Aerial parts of Dorema aucheri exhibit a lipophilic exudate material which was shown to contain several flavone methyl esters.
Zeitschrift für Naturforschung C | 2005
Eckhard Wollenweber; Marco Dörsam; Marion Dörr; James N. Roitman; Karin M. Valant-Vetschera
Abstract Several species of Nicotiana and Solanum and further members of the Solanaceae have been examined for their exudate flavonoids. Most of the aglycones are widespread flavonols, but rare and unusual flavonols were also found, e.g. in exudates of Physalis and Solanum species. Flavones occur throughout the family, but flavanones are rare. Our data are presented in comparison to previous results. The chemodiversity of the observed structures is discussed in relation to literature reports. Morphological and systematic aspects are briefly addressed.
Zeitschrift für Naturforschung C | 1997
Eckhard Wollenweber; Marion Dörr; Hannelore Fritz; Sabine Papendieck; George Yatskievych; James N. Roitman
Abstract A series of Asteraceae, belonging to the tribes Astereae, Eupatorieae, Helenieae and Heliantheae, have been analyzed for the presence of flavonoid aglycones accumulated on leaf and stem surfaces. Methyl ethers of apigenin, luteolin, kaempferol, and quercetin as well as methyl ethers of their relevant 6 -hydroxy derivatives were abundant, whereas 8 -O-substi-tuted derivatives and flavanones were encountered only occasionally; 6 ,8 -di-O-substituted flavonols were found in only one species.
Zeitschrift für Naturforschung C | 1992
Eckhard Wollenweber; Marion Dörr; Abdolhossein Rustaiyan; James N. Roitman; Earl H. Graven
Seven species of Salvia and one species of Trichostema were analyzed for their exudate flavonoids. They were found to exhibit flavonoid aglycones in various numbers and different patterns. Most of these are flavones, in which 6-methoxy-substituted compounds predominate.
Zeitschrift für Naturforschung C | 2002
Eckhard Wollenweber; Rüdiger Wehde; Marion Dörr; Jan F. Stevens
Externally accumulated flavonoid aglycones have been found for the first time in Nonea species. They exhibit only flavones, one of thembeing the rare tricetin-4ʹ-methyl ether. Within the subfamily Boraginoideae, exudate flavonoids appear to be a rare character.
Phytochemistry | 1993
F. Javier Arriaga-Giner; Eckhard Wollenweber; Marion Dörr
Abstract The leaf exudate of Empetrum nigrum contains, among other phenolic constituents, two novel bibenzyls. These were identified by spectroscopic methods as 3,5,3′-trihydroxy-4-methoxybibenzyl and 3,3′-dihydroxy-4,5-dimethoxybibenzyl.
Zeitschrift für Naturforschung C | 2004
Eckhard Wollenweber; Marion Dörr; Bruce A. Bohm; James N. Roitman
Abstract Leaf glands of Ceanothus species excrete a lipophilic material that contains a variety of flavonoids. Most of these are aglycones, but some glycosides were also observed. Seven out of eight species exhibit flavonols, whereas flavones are excreted by only one species. Four species produce flavanones and dihydroflavonols; one excretes a remarkable quantity of flavonol glycosides. The exudate flavonoids thus form different patterns that might be characteristic for different Ceanothus species.
Zeitschrift für Naturforschung C | 2003
Eckhard Wollenweber; Marion Dörr; Marco Dörsam; Abu El-Hamed Hassan; Ahmed A. Ahmed; Mohamed-Elamir F. Hegazy; Klaus-Peter Zeller
The resinous material accumulated on aerial parts of Madia species is shown to consist mainly of diterpenes, containing a series of flavonoid aglycones. A6- and/or 8-O-substitution is characteristic for many of these flavonoids. Three known rare diterpenes were found and the structure elucidation of a diterpene with a new carbon skeleton, named madiaol, is reported.