Antiplasmodial Quinones from the Rhizomes of Kniphofia foliosa

作者：Induli Martha; Gebru Meron; Abdissa Negera; Akala Hosea; Wekes Ingrid; Byamukama Robert^*; Heydenreich Matthias; Murunge Sylvia; Dagne Ermias; Yenesew Abiy

来源：Natural Product Communications, 2013, 8(9): 1261-1264.

• Kniphofia foliosa
• Rhizomes
• 10-Acetonylknipholone cyclooxanthrone
• Chryslandicin 10-methyl ether
• Joziknipholones A and B
• Knipholone anthrone
• Malaria

Extracts of the rhizomes of Kniphofia foliosa exhibited antiplasmodial activities against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum with IC50 values of 3-5 mu g/mL. A phenyloxanthrone, named 10-acetonylknipholone cyclooxanthrone (1) and an anthraquinone-anthrone dimer, chryslandicin 10-methyl ether (2), were isolated from the rhizomes, along with known quinones, including the rare phenylanthraquinone dimers, joziknipholones A and B. The structures of these compounds were determined based on spectroscopic data. This is the second report on the occurrence of the dimeric phenylanthraquinones in nature. In an in vitro antiplasmodial assay of the isolated compounds, activity was observed for phenylanthraquinones, anthraquinone-anthrone dimers and dimeric phenylanthraquinones, with joziknipholone A being the most active. The new compound, 10-acetonylknipholone cyclooxanthrone, also showed anti-plasmodial activity. In an in vivo assay, knipholone anthrone displayed marginal antimalarial activity.

• 出版日期2013-9