title: Rearranged lanostane triterpenoids from Abies sachalinensis (III).
abstract: To isolate more rearranged lanostane-type triterpenes from Abies sachalinensis, continuous chemical investigation of the ethyl acetate soluble fraction of the methanol extract of A. sachalinensis afforded two new rearranged lanostane-type triterpenes (1, 2). Their structures were elucidated to be 3,4-seco-4(28),7,12,24-mariesatetraen-26,23-olide-23-hydroxy-3-oic acid (1) and ethyl 3,4-seco-8(14-->13R)abeo-17,13-friedo-4(28),7,14,24-lanostatetraen-26,23-olide-23-hydroxy-3-oate (2), respectively. The structure of these compounds was determined by spectral studies, especially by two-dimensional (2D)-NMR and high-resolution (HR)-MS. Compounds 1 and 2 have a tautomeric lactone structure in the side chain.
authors.affiliation: School of Traditional Chinese Medicines, Shenyang Pharmaceutical University, Shenyang City, People's Republic of China.
authors.forename: Hui Yuan
authors.initials: HY
authors.lastname: Gao
authors.forename: Li Jun
authors.initials: LJ
authors.lastname: Wu
authors.forename: Takahisa
authors.initials: T
authors.lastname: Nakane
authors.forename: Osamu
authors.initials: O
authors.lastname: Shirota
authors.forename: Masanori
authors.initials: M
authors.lastname: Kuroyanagi