AbstractThe fungicidal activity of analogues of β‐thujaplicin, a natural product responsible for the durability of heartwood of several cupressaceous trees, was investigated in vitro on the growth of different white and brown rot fungi involved in wood biodegradation, Coriolus versicolor, Phanerochaete chrysosporium, Poria placenta and Gloephyllum trabeum. The study shows that 2‐hydroxycyclohepta‐2,4,6‐trienone (tropolone), easily prepared according to a literature procedure, possesses interesting fungicidal activity when compared to β‐thujaplicin, azaconazole, tebuconazole and copper oxine, which suggests this compound should be examined further as a potential biocide for wood preservation.© 2001 Society of Chemical Industry