title: Triterpenoid saponins from Astragalus wiedemannianus Fischer.
abstract: Three cycloartane-type triterpene glycosides were isolated from Astragalus wiedemannianus together with eight known secondary metabolites namely cycloastragenol, cycloascauloside B, astragaloside IV, astragaloside VIII, brachyoside B, astragaloside II, astrachrysoside A, and astrasieversianin X. The structures were established mainly by a combination of 1D and 2D-NMR techniques as 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl]-25-O-beta-D-glucopyranosyl-20(R),24(S)-epoxy-3beta,6alpha,16beta,25-tetrahydroxycycloartane, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl]-6-O-beta-D-glucopyranosyl-24-O-alpha-(4'-O-acetoxy)-L-arabinopyranosyl-16-O-acetoxy-3beta,6alpha,16beta,24(S),25-pentahydroxycycloartane, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl]-6-O-beta-D-glucopyranosyl-24-O-alpha-L-arabinopyranosyl-16-O-acetoxy-3beta,6alpha,16beta,24(S),25-pentahydroxycycloartane. To the best of our knowledge, the presence of an arabinose moiety on the acyclic side chain of cycloartanes is reported for the first time.
authors.affiliation: Ege University, Faculty of Science, Department of Chemistry, Bornova, Izmir, Turkey.
authors.forename: Emre
authors.initials: E
authors.lastname: Polat
authors.forename: Erdal
authors.initials: E
authors.lastname: Bedir
authors.forename: Angela
authors.initials: A
authors.lastname: Perrone
authors.forename: Sonia
authors.initials: S
authors.lastname: Piacente
authors.forename: Ozgen
authors.initials: O
authors.lastname: Alankus-Caliskan
mesh_terms: D001089:Arabinose / Q000032:analysis; D027883:Astragalus Plant / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D012503:Saponins / Q000737:chemistry / Q000302:isolation & purification*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D010936:Plant Extracts; D012503:Saponins; D014315:Triterpenes; D001089:Arabinose