Conduritol F glucosides and terpenoid glucosides from Cynanchum liukiuense and distribution of conduritol F glucosides in several Asclepiadaceous plants

Conduritol F 3-0- and 4-O-glucosides were obtained from Cynanchum liukiuense, along with conduritol F which was identified in all Asclepiadaceous plants examined, Tylophora tanakae, Asclepias curassavica and A. fruticosa, as well as in Marsdenia tomentosa. The pattern of the glucosidic linkage to conduritol F differed between individual species, 2-O-glucoside from T tanakae and M. tomentosa, 3-O-glucoside from A. curassavica, but none from A. fruticosa. Along with conduritol F glucosides, an 11-glucosyloxy-megastigmane and a monoterpenoid glucoside were isolated from C. liukiuense.