5'-O-demethyldioncophylline A, a new antimalarial alkaloid from triphyophyllum peltatum.
From the root bark of Triphyophyllum peltatum, the new naphthylisoquinoline alkaloid 5'-O-demethyldioncophylline A has been isolated. Its otherwise difficult separation from the largely dominating main alkaloid, dioncophylline A, was greatly facilitated by a bromination-benzylation procedure. From the resulting derivative, a crystal structure analysis with an anomalous X-ray diffraction was achieved, allowing confirmation of the full absolute stereostructure of the new alkaloid. The structure was further corroborated by a partial synthesis from dioncopeltine A. The natural product was shown to exhibit antimalarial activity against erythrocytic forms of Plasmodium falciparum.
Bringmann
Gerhard
G
Institut für Organische Chemie der Universität, Am Hubland, D-97074, Würzburg, Germany
Saeb
Wael
W
God
Ralf
R
Schäffer
Manuela
M
François
Guido
G
Peters
Karl
K
Peters
Eva Maria
EM
Proksch
Peter
P
Kurt Hostettmann
Assi
Laurent Aké
LA