New polyoxypregnane glycosides from the roots of Marsdenia tenacissima. - Pang, Xu; Kang, Li-Ping; Yu, He-Shui; Zhao, Yang; Han, Li-Feng; Zhang, Jie; Xiong, Cheng-Qi; Zhang, Li-Xia; Yu, Li-Yan; Ma, Bai-Ping (Steroids, 2015)