Revision of the absolute configuration of plumericin and isoplumericin from Plumeria rubra.
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.
Elsässer
Brigitta
B
Department of Chemistry, University of Paderborn, Warburger Strasse 100, D-33098 Paderborn.
Krohn
Karsten
K
Akhtar
M Nadeem
MN
Flörke
Ulrich
U
Kouam
Simeon F
SF
Kuigoua
Merlin Guy
MG
Ngadjui
Bonaventure T
BT
Abegaz
Berhanu M
BM
Antus
Sándor
S
Kurtán
Tibor
T
D029062:Apocynaceae / Q000737:chemistry*; D007192:Indenes / Q000737:chemistry*; D039823:Iridoids; D008958:Models, Molecular; D015394:Molecular Structure
D007192:Indenes; D039823:Iridoids; C516952:isoplumericin; C068511:plumericin