Antimalarial activity of pyrroloiminoquinones from the Australian marine sponge Zyzzya sp.

Eskitis Institute, Griffith University, Brisbane, QLD 4111, Australia.
Journal of Medicinal Chemistry (Impact Factor: 5.61). 06/2012; 55(12):5851-8. DOI: 10.1021/jm3002795
Source: PubMed

ABSTRACT A new bispyrroloiminoquinone alkaloid, tsitsikammamine C (1), displayed potent in vitro antimalarial activity with IC(50) values of 13 and 18 nM against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum, respectively. Tsitsikammamine C (1) displayed selectivity indices of >200 against HEK293 cells and inhibited both ring and trophozoite stages of the malaria parasite life cycle. Previously reported compounds makaluvamines J (2), G (3), L (4), K (5) and damirones A (6) and B (7) were also isolated from the same marine sponge (Zyzzya sp.). Compounds 2-4 displayed potent growth inhibitory activity (IC(50) < 100 nM) against both P. falciparum lines and only moderate cytotoxicity against HEK293 cells (IC(50) = 1-4 μM). Makaluvamine G (3) was not toxic to mice and suppressed parasite growth in P. berghei infected mice following subcutaneous administration at 8 mg kg(-1) day(-1).

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