IDENTIFICATION OF AN EPOXY-INTERMEDIATE RESULTING FROM THE FUNGAL METABOLISM OF A PRENYLATED ISOFLAVONE

Article abstract of DOI:10.1016/S0031-9422(00)97923-8

Key Word Index - Botrytis cinerea; Hyphomycetes; 7-O-methyl-2,3-dehydrokievitone epoxide; 7-O-methyl-2,3-dehydrokievitone glycol; prenylated isoflavone; fungal metabolism; stereochemistry. - Abstract - The prenylated isoflavone 2,3-dehydrokievitone was methylated with ethereal diazomethane to yield the corresponding 7-O-methyl derivative.This was metabolized by Botrytis cinerea to give 7-O-methyl-2,3-dehydrokievitone epoxide and 7-O-methyl-2,3-dehydrokievitone glycol.The structures of these metabolites were established by standard spectroscopic methods (UV, MS and 1H NMR), and by chemical conversion.Both compounds were found to possess the S-absolute stereochemistry.The epoxide is an analogue of the key metabolic intermediate thought to be involved in the formation, by fungi, of various dihydrofurano-, dihydropyrano- and 2,3-dihydroxy-3-methylbutyl-substituted isoflavones from precursor compounds containing a prenyl side-chain with ortho-hydroxylation.