Kaurane-Type Diterpenes from Fern Frond Exudates
نویسندگان
چکیده
The viscid exudate found on fronds o f the fern, Cheilanthes kaulfussii, consists of terpenoids in which flavonoid aglycones are dissolved. One of the terpenes is shown to be em-kaur-16-en-19-oic acid. The farinose frond exudate of Notholaena pallens contains this acid as the major constituent and its 3 /?-hydroxy derivative, together with flavonoid aglycones as minor components. In N. incana, two of the diterpenes that form the farinose exudate along with flavonoid aglycones have been identified as 16/?-enr-kauran-17-oic acid and 16/?,17-dihydroxy-3-oxo-en?-kaurane (abbeokutone).
منابع مشابه
Pterisolic acids A-F, new ent-kaurane diterpenoids from the fern Pteris semipinnata.
Six new ent-15-oxokauran-19-oic acid derivatives, named pterisolic acids A-F (1-6), were isolated from the ethanol extract of the fern Pteris semipinnata (Pteridaceae), and the structures of these new ent-kauranoids were elucidated on the basis of extensive spectroscopic studies and single crystal X-ray diffraction analysis.
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