New Triterpenes from the Frond Exudate of the Fern Notholaena vigida
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چکیده
The farinose coating on the lower frond surface of the fern Notholaena rigida Dav. was shown pre viously to contain the flavones scutellarein-6,7,4'trimethyl ether and scutellarein-6 ,7-dimethyl ether as well as minor amounts of apigenin, apigenin-4'methyl ether, and apigenin-7,4'-dimethyl ether [1], The exudate material also contains a considerable amount of terpenoids, one of which has been as sumed earlier to be a triterpenoid with a cycloartenol skeleton [1], The structure of this product as well as that of a second product isolated later have now been elucidated by detailed spectroscop ic studies.
منابع مشابه
A dihydroflavonol with taxonomic significance from the fern Notholaena sulphurea.
A new flavonoid, 2,3-trans-5,2'-dihydroxy-7,8-dimethoxy-dihydroflavonol-3-O-acetate, was isolated from the farinose coating on the lower leave surface of the fern, Notholaena sulphurea. The 2,3-cis diastereoisomer was isolated as a co-constituent. This novel acylated flavonoid is characteristic for the chemotype of N. sulphurea exhibiting yellow frond exudate. Its orrurrence underlines the affi...
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