To obtain a new cryptoporic acid derivative showing antimicrobial actions, derived from a compound prepared from a fruit body of Cryptoporus volvatus being a mushroom of the family Polyporaceae.
This compound is shown by formula I (R1, R2 and R3 are each H, an alkyl or an alkali metal; R4 is an alkyl, a hydroxyalkyl or an acetoxyalkyl; R5 is an oxygen atom, hydroxy, methyl or an epoxy ring) or its dimer such as a compound of formula II. The compound is obtained, for example, by finely cutting a fruit body of Cryptoporus volvatus (e.g. collected at Mito forest park in Ibaragi Prefecture), immersing the finely cut fruit body in a solvent such as ethyl acetate or the like at a room temperature for 1-3 days, extracting an active ingredient, separating, purifying and oxidizing or epoxidizing the prepared compound by a routine procedure.
TAKAHASHI AKIRA
MASUDA JUNICHI
SEGAWA TOSHIAKI
