Structure and Fungicidal Activity of Secondary Metabolites Isolated from b-3.

Two new harziane diterpenes (-), five undescribed cyclonerane sesquiterpenes (-), and three known compounds, 11-cycloneren-3, 7, 10-triol (), harziandione (), and dehydroacetic acid (), were isolated from b-3. Their structures were elucidated via comprehensive inspection of spectral evidence in HRESIMS and 1D and 2D NMR, and the absolute configuration of - was confirmed by NMR, ECD calculation, as well as Mosher's method. In vitro fungicidal activity showed that some compounds showed great inhibitory activity against pathogenic fungi, including , , , and , among which compound showed 100% inhibition of and . The in vivo activity test showed that compound was 65.8% effective against and compound can be used as a lead compound for the development of biopesticides that inhibit . This study elucidated the bioactivity of secondary metabolites of and indicated the direction for the subsequent development of the biological control activity of .