Cycloartane glycosides from Astragalus stereocalyx Bornm

Twelve cycloartane glycosides among which six compounds were isolated from the roots of Astragalus stereocalyx. Their structures were established by 1D- and 2D-NMR experiments along with ESIMS and HRMS analysis. Three compounds are based on cycloasgenin C as aglycon, whereas three other compounds show as aglycon a cycloasgenin C derivative, characterized by the occurrence of the hydroxyl group at position 20 which is not involved in the usual 20,24-epoxy function. All the compounds were screened for their antiproliferative activity versus a number of cancer cell lines. [Display omitted] ► Twelve cycloartane-type glycosides have been isolated from the roots of Astragalus stereocalyx among them, there are six cycloartane glycosides. ► Three compounds possess an aglycon characterized by the occurrence of a hydroxyl group at C-20. ► All the compounds were tested for their antiproliferative activity. Six cycloartane-type triterpene glycosides were isolated from Astragalus stereocalyx along with six known cycloartane-type glycosides. Their structures were established by the extensive use of 1D and 2D-NMR experiments along with ESIMS and HRMS analysis. Three compounds are based on an aglycon characterized by the occurrence of an unusual hydroxyl group at position 20, whereas three other compounds are based on cycloasgenin C as aglycon, so far reported from Astragalus spp. All the compounds were tested for their cytotoxic activity against a number of cancer cell lines. One compound exhibited activity versus human cervical cancer (Hela) with an IC 50 value = 10 μM.