Fusidic acid derivatives from the endophytic fungus F47.

Fusidic acid, a representative member of fungal fusidane triterpenoids, has been clinically used as an antibiotic. In the present study, fusidic acid (), and its known analogs 16-desacetylfusidic acid () and 3,20-dihydroxy-protosta-16,24-dien-29-oic acid (), together with one new derivative acremonidiol A (), were isolated from the endophytic fungus, F47. Their structures were determined by MS and NMR. The spectroscopic data of are firstly reported here. The antibacterial efficacies of - were evaluated against four selected Gram-positive or Gram-negative bacteria. As expected, only compound showed strong inhibitory effect on Gram-positive bacteria and .