title: Revision of the absolute configuration of plumericin and isoplumericin from Plumeria rubra.
abstract: The absolute configurations of plumericin (1) and isoplumericin (2), isolated from Plumeria rubra, were re-assigned based on a combination of X-ray crystal-structure determination and quantum-mechanical calculations of their circular dichroism (CD) spectra. The experimental CD spectra showed an excellent match with those calculated for the (1S,5R,8R,9R,10R) absolute configuration (corresponding to ent-1 and ent-2, resp.), opposite to that generally accepted and published in the literature. Since the (false) plumericin configuration has been often used to derive the absolute configuration of related iridoids by chemical correlation, their absolute configurations also have to be reconsidered.
authors.affiliation: Department of Chemistry, University of Paderborn, Warburger Strasse 100, D-33098 Paderborn.
authors.forename: Brigitta
authors.initials: B
authors.lastname: Elsässer
authors.forename: Karsten
authors.initials: K
authors.lastname: Krohn
authors.forename: M Nadeem
authors.initials: MN
authors.lastname: Akhtar
authors.forename: Ulrich
authors.initials: U
authors.lastname: Flörke
authors.forename: Simeon F
authors.initials: SF
authors.lastname: Kouam
authors.forename: Merlin Guy
authors.initials: MG
authors.lastname: Kuigoua
authors.forename: Bonaventure T
authors.initials: BT
authors.lastname: Ngadjui
authors.forename: Berhanu M
authors.initials: BM
authors.lastname: Abegaz
authors.forename: Sándor
authors.initials: S
authors.lastname: Antus
authors.forename: Tibor
authors.initials: T
authors.lastname: Kurtán
mesh_terms: D029062:Apocynaceae / Q000737:chemistry*; D007192:Indenes / Q000737:chemistry*; D039823:Iridoids; D008958:Models, Molecular; D015394:Molecular Structure
chemical_list: D007192:Indenes; D039823:Iridoids; C516952:isoplumericin; C068511:plumericin