Antimicrobial Triterpenoid Glycosides from Cephalaria scoparia

Five new oleanane-type triterpenoid glycosides (1-5), named scoposides A-E, along with one known bisdesmosidic triterpene glycoside, were isolated from the aerial parts of Cephalaria scoparia. Three prosapogenins (2a-4a) were also obtained after alkaline hydrolysis of the bisdesmosidic compounds 2-4. The structures of compounds 1-5 were determined by spectroscopic (ID and 2D NMR, HRESIMS) and chemical methods. The antimicrobial effects of compounds 1-5 were evaluated against a small panel of Gram-positive and Gram-negative bacteria.