title: Studies on the Constituents of Adelostemma gracillimum.
abstract: The glycone portion of the glycoside of ADELOSTEMMA GRACILLIMUM Hook. f. (Asclepiadaceae) was investigated. Three known polyoxypregnane ester-type aglycones, penupogenin ( 1) (1, 2), kidjoranine ( 2) (1, 3), and gagamine ( 3) (4, 5), and one new compound named gracigenin ( 4) were isolated and their structures were characterized on the basis of spectroscopic evidence, and that of ( 4) was determined by X-ray crystallography. It was found to possess an unprecedented 8,14- SECO-polyoxypregnane ester-type skeleton, and 4 is the first compound with this C (21)-steroid type skeleton to be found in nature.
authors.affiliation: Laboratory of Phytochemistry, Kunming Institute of Botany, Academia Sinica, Kunming 650204, Yunnan, People's Republic of China.
authors.forename: Q Z
authors.initials: QZ
authors.lastname: Mu
authors.forename: Y M
authors.initials: YM
authors.lastname: Shen
authors.forename: Q L
authors.initials: QL
authors.lastname: Zhou
authors.forename: S Q
authors.initials: SQ
authors.lastname: Wang
authors.forename: B
authors.initials: B
authors.lastname: Wu
authors.forename: Q T
authors.initials: QT
authors.lastname: Zheng