Antimalarial xanthones from Calophyllum caledonicum and Garcinia vieillardii.
The antimalarial activity of 22 xanthones against chloroquino-resistant strains of Plasmodium falciparum was evaluated. Natural caloxanthone C (1), demethylcalabaxanthone (2), calothwaitesixanthone (3), calozeyloxanthone (4), dombakinaxanthone (5), macluraxanthone (6), and 6-deoxy-gamma-mangostin (7) were isolated from Calophyllum caledonicum. 1,6-dihydroxyxanthone (8), pancixanthone A (9), isocudraniaxanthone B (10), isocudraniaxanthone A (11), 2-deprenylrheediaxanthone B (12) and 1,4,5-trihydroxyxanthone (13) were isolated from Garcinia vieillardii. Moreover, synthetic compounds (14-22) are analogues or intermediates of xanthones purified from Calophyllum caledonicum (Oger J.M., Morel C., Helesbeux J.J., Litaudon M., Seraphin D., Dartiguelongue C., Larcher G., Richomme P., Duval O. 2003. First 2-Hydroxy-3-Methylbut-3-Enyl substituted xanthones isolated from Plants: structure elucidation, synthesis and antifungal activity. Natural Product Research 17(3), 195-199; Helesbeux J.J., Duval O., Dartiguelongue C., Seraphin D., Oger J.M., Richomme P., 2004. Synthesis of 2-hydroxy-3-methylbut-3-enyl substituted coumarins and xanthones as natural products. Application of the Schenck ene reaction of singlet oxygen with ortho-prenylphenol precursors. Tetrahedron 60(10), 2293-2300). The relationship between antimalarial activity and molecular structure of xanthones has also been explored. The most potent xanthones (2), (3) and (7) (IC50 = c.a. 1.0 microg/mL) are 1,3,7 trioxygenated and prenylated on the positions 2 and 8.
SONAS, UFR des Sciences pharmaceutiques et Ingénierie de la santé, 16, Bd Daviers, Angers, France.
Anne-Emmanuelle
AE
Hay
Jean-Jacques
JJ
Hélesbeux
Olivier
O
Duval
Medhi
M
Labaïed
Philippe
P
Grellier
Pascal
P
Richomme
D000818:Animals; D000962:Antimalarials / Q000494:pharmacology*; D029759:Calophyllum / Q000737:chemistry*; D029760:Garcinia / Q000737:chemistry*; D010963:Plasmodium falciparum / Q000187:drug effects; D013329:Structure-Activity Relationship; D044004:Xanthones / Q000494:pharmacology*
D000962:Antimalarials; D044004:Xanthones