title: Antimalarial sesquiterpene lactones from Distephanus angulifolius.
abstract: Combined use of bioassay-guided fractionation based on in vitro antiplasmodial assay and dereplication based on HPLC-PDA-MS-SPE-NMR led to isolation of (6S,7R,8S)-14-acetoxy-8-[2-hydroxymethylacrylat]-15-helianga-1(10),4,11(13)-trien-15-al-6,12-olid and (5R,6R,7R,8S,10S)-14-acetoxy-8-[2-hydroxymethylacrylat]-elema-1,3,11(13)-trien-15-al-6,12-olid, along with vernodalol, vernodalin, and 11,13beta-dihydroxyvernodalin from extract of Distephanus angulifolius. All compounds were identified by spectroscopic methods, including 1D and 2D homo- and heteronuclear NMR experiments. The isolated compounds showed IC(50) values in the range 1.6-3.8 microM and 2.1-4.9 microM against chloroquine sensitive D10 and chloroquine resistant W2 Plasmodium falciparum strains, respectively.
authors.affiliation: Department of Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
authors.forename: Martin M
authors.initials: MM
authors.lastname: Pedersen
authors.forename: Jude C
authors.initials: JC
authors.lastname: Chukwujekwu
authors.forename: Carmen A
authors.initials: CA
authors.lastname: Lategan
authors.forename: Johannes van
authors.initials: Jv
authors.lastname: Staden
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Smith
authors.forename: Dan
authors.initials: D
authors.lastname: Staerk
mesh_terms: D000818:Animals; D000962:Antimalarials / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D007783:Lactones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008958:Models, Molecular; D010963:Plasmodium falciparum / Q000187:drug effects*; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D035741:Vernonia / Q000737:chemistry*
chemical_list: D000962:Antimalarials; D007783:Lactones; D012717:Sesquiterpenes