Nine new phenanthrenes (1-9) and a new benzyl glycoside (10) together with 45 known compounds were isolated from the rhizomes of Bletilla formosana. The structures of 1-10 were elucidated primarily on the basis of their 1D and 2D NMR spectroscopic data. Most of the isolated compounds were evaluated for their anti-inflammatory activities. The results showed that IC50 values for the inhibition of superoxide anion generation and elastase release ranged from 0.2 to 6.5 μM and 0.3 to 5.7 μM, respectively. Structure-activity relationships of the isolated compounds were also investigated. The inhibitory potencies were determined as phenanthrenes > bibenzyls > biphenanthrenes.
All Science Journal Classification (ASJC) codes