Structures of minor glucosides from the Far Eastern high-mountain endemic plant Ligularia alticola Worosch. Screening of bioactivity for some glycosides from L. alticola

Two new minor eremophilane-type sesquiterpene glucosides, alticolosides H ( 1 ) and I ( 2 ) along with known earlier lignan glucosides (−)-pinoresinol-4′- O -β- d -glucoside, plucheoside D 1 and tortoside F were isolated from aerial parts of the endemic Far Eastern species Ligularia alticola Worosch. (Family Asteraceae). Structures of the glycosides were elucidated by 2D NMR spectroscopy and HRESIMS. The absolute stereochemistry of 1 and 2 was determined by comparison of experimental and calculated ECD spectra. The screening of biological activities of the compounds earlier found in L. alticola including the influence on the biofilm formation by Yersinia pseudotuberculosis , cytotoxic activities against different cancer cell lines and the ability to reduce ROS levels in the macrophages pre-stimulated with pro-inflammatory LPS from E. coli was carried out.