New Flavonoids from the Exudate of Baccharis bigelovii (Asteraceae)
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چکیده
New Flavonoids from the Exudate of Baccharis bigelovii (Asteraceae) Francisco J. Arriaga-Giner Departamento de Qui'mica Orgänica, Universidad A utönom a de Madrid, Madrid, Spain Eckhard Wollenweber, Dagmar Hradetzky Institut für Botanik der Technischen Hochschule Darmstadt, Bundesrepublik Deutschland Z. Naturforsch. 41c, 946—948 (1986); received June 4, 1986 Baccharis bigelovii (Asteraceae), Leaf and Stem Exudate, Flavonoid A glycones, 7-Benzoyl-chrysin Four flavonoids have been identified from the leaf and stem resin produced by Baccharis bigelovii (Asteraceae) in addition to twelve previously described aglycones. A flavonol (alnusin) and a dihydroflavonol (alnustinol) with 3,5,7-trihydroxy substitution had both been reported only twice before. The novel compound 2ß,5,7-trihydroxyflavanone is remarkable for its 2ß-substitution at the heterocyclic ring. 7-Benzoyl-chrysin is the first flavone aglycone found as ester and the first flavonoid aglycone at all that is esterified with an aromatic acid.
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