Steroidal glycosides from Asclepias fruticosa L

Five novel steroidal glycosides 2-6 were isolated from the whole plant of Asclepias fruticosa L. (Asclepiadaceae). The structures of these steroidal glycosides were determined on the basis of spectral and chemical evidence. All of these glycosides contain 2,6-dideoxyhexopyranoses as component sugars and their structures were elucidated as polyoxypregnane-type glycosides, which have lineolon as the aglycone moiety.