Three new hopane-type triterpenoids from the aerial part of Adiantum capillus-veneris and their antimicrobial activities.

Three new hopane-type triterpenoids (1-3), fern-7(8)-en-19α, 28-diol (1), pteron-14-ene-7α,19α,28-triol (2) and 3β,4α,25-trihydroxyfilican (3), were isolated from the aerial parts of Adiantum capillus-veneris. Their structures were determined by NMR spectroscopic and mass spectrometric data. Compounds 2 and 3 exhibited remarkable antifungal activity against Helminthosporium maydis and Alternaria alternata with MIC values of 12.5-3.125 μg/mL, and compound 3 also against Verticillium dahliae Kleb with an MIC value of 3.125 μg/mL. In addition, compounds 1-3 also displayed weak antibacterial activity against Micrococcus lysodeikticus, Bacterium paratyphosum B and Pseudomonas aeruginosa with an MIC value of 100 μg/mL.