Assessment of the antiprotozoal activity of Galphimia glauca and the isolation of new nor-secofriedelanes and nor-friedelanes.
Four new terpenoids, comprising three nor-secofriedelanes (1-3) and one nor-friedelane (4), were isolated from Galphimia glauca, together with the known flavonol quercetin and the sterols stigmasterol and sitosterol 3-O-beta-D-glucoside. The structure elucidation of the new isolates was conducted by 1D and 2D NMR techniques. Compounds 1-4 were given the trivial names galphin A, galphin B, galphin C, and galphimidin, respectively. All isolates were tested for in vitro antiprotozoal and cytotoxic activities. Quercetin was the only substance isolated that showed any antiprotozoal activity, and this was weak; the IC(50) values were 14 microM against Plasmodium falciparum K1, 13.2 microM against Trypanosoma brucei brucei, and 63.8 microM against Leishmania donovani. Quercetin was found to be inactive against KB cells (IC(50) = 295.8 microM).
del Rayo Camacho
Maria
M
Centre for Pharmacognosy and Phytotherapy, and Department of Pharmaceutical and Biological Chemistry, The School of Pharmacy, University of London, 29-39 Brunswick Square, UK.
Phillipson
J David
JD
Croft
Simon L
SL
Marley
Dereck
D
Kirby
Geoffrey C
GC
Warhurst
David C
DC
D000818:Animals; D000981:Antiprotozoal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D031582:Galphimia / Q000737:chemistry*; D007893:Leishmania donovani / Q000187:drug effects; D010963:Plasmodium falciparum / Q000187:drug effects; D013057:Spectrum Analysis; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D014346:Trypanosoma brucei brucei / Q000187:drug effects; D014407:Tumor Cells, Cultured
D000981:Antiprotozoal Agents; D014315:Triterpenes; C421805:friedelane