Antimalarial activity of azafluorenone alkaloids from the Australian tree Mitrephora diversifolia.
Mass-directed isolation of the CH2Cl2/MeOH extract from the roots of the Australian tree Mitrephora diversifolia resulted in the purification of the new azafluorenone alkaloid 5,8-dihydroxy-6-methoxyonychine (1) together with the known natural product 5-hydroxy-6-methoxyonychine (2). The structures of 1 and 2 were determined by extensive 1D and 2D NMR and MS data analyses. Both compounds were isolated during a drug discovery program aimed at the identification of new antimalarial leads from a prefractionated natural product library. When tested against two different strains of the parasite Plasmodium falciparum (3D7 and Dd2), 2 displayed IC(50) values of 9.9 and 11.4 microM, respectively, while 1 showed minimal activity.
Mueller
Daniela
D
Eskitis Institute, Griffith University, Brisbane, QLD 4111, Australia.
Davis
Rohan A
RA
Duffy
Sandra
S
Avery
Vicky M
VM
Camp
David
D
Quinn
Ronald J
RJ
D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D000818:Animals; D029061:Annonaceae / Q000737:chemistry*; D000962:Antimalarials / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001315:Australia; D001372:Aza Compounds / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D005449:Fluorenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D006801:Humans; D015394:Molecular Structure; D018517:Plant Roots / Q000737:chemistry; D010963:Plasmodium falciparum / Q000187:drug effects*; D014197:Trees / Q000737:chemistry
D000470:Alkaloids; D000962:Antimalarials; D001372:Aza Compounds; D005449:Fluorenes