New Flavonol Acetates from the Frond Exudate of the Fern Notholaena aschenborniana

Abstract

Abstract The farinose frond exudate of the fern Notholaena aschenborniana was previously shown to contain a mono­ acetate and a mono-butyrate of a 8-hydroxyflavonol as major constituents and the same pair of esters of a second 8-hydroxyflavonol as minor components. Now we have been able to identify the 8-acetates of two further flavonols. The structures of 5-hydroxy-3,7,2′,3′,4′-pentamethoxy-8-acetoxyflavone and 5,4′-dihydroxy-3,7,3′-trimethoxy-8-acetoxyflavone have been elucidated by spectroscopic methods. Both are novel natural products.