title: Guaiane dimers from Xylopia vielana.
abstract: From the leaves of Xylopia vielana (Annonaceae) two dimeric guaianes named vielanins D and E were isolated and structurally elucidated by mass and NMR spectroscopy. Vielanin D and E consist of bridged ring systems formally representing the Diels-Alder products from the hypothetical guaiane-type monomers. Due to a hemiketal function at C-8' both compounds occurred as epimeric mixtures.
authors.affiliation: National Center for Natural Science and Technology, Institute of Chemistry, Hoang Quoc Viet Road, Cau Giay, Hanoi, Viet Nam.
authors.forename: Christine
authors.initials: C
authors.lastname: Kamperdick
authors.forename: Nguyen Minh
authors.initials: NM
authors.lastname: Phuong
authors.forename: Günter
authors.initials: G
authors.lastname: Adam
authors.forename: Tran
authors.initials: T
authors.lastname: Van Sung
mesh_terms: D029061:Annonaceae / Q000737:chemistry*; D003508:Cycloheptanes / Q000737:chemistry* / Q000302:isolation & purification*; D019281:Dimerization; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D018515:Plant Leaves / Q000737:chemistry; D045789:Sesquiterpenes, Guaiane / Q000737:chemistry* / Q000302:isolation & purification*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D003508:Cycloheptanes; D045789:Sesquiterpenes, Guaiane; C421026:guaiane