title: Five new C21 steroidal glycosides from Cynanchum komarovii Al.Iljinski.
abstract: Five new C21 steroidal glycosides, namely, komarosides D (1), E (2), F (3), G (4), and H (5), along with two known C21 steroidal glycosides cynatratoside E (6) and hancoside A (7), were isolated from the ethanol extract of the roots of Cynanchum komarovii Al. Iljinski (Asclepiadaceae). Their structures were determined by physiochemical and spectroscopic analysis. Among these glycosides, five had an aberrant 13,14:14,15-disecopregnane-type skeleton, and the other two had normal four-ring C21 steroid skeletons. The existence of more than one type of C21 steroid skeleton in one species is rare in the plants of the family Asclepiadaceae, and this has chemotaxonomic significance for this species.
authors.affiliation: The State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China.
authors.forename: Wang
authors.initials: W
authors.lastname: Liqin
authors.forename: Shen
authors.initials: S
authors.lastname: Yuemao
authors.forename: Xu
authors.initials: X
authors.lastname: Xing
authors.forename: Wei
authors.initials: W
authors.lastname: Yuqing
authors.forename: Zhou
authors.initials: Z
authors.lastname: Jun
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D031105:Cynanchum / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D018517:Plant Roots / Q000737:chemistry; D013256:Steroids / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D006027:Glycosides; D010936:Plant Extracts; D013256:Steroids