Abstract Six known compounds, namely two halisulfates 1 and 2 and four epidioxy sterols 3–6, were isolated from the marine sponge Coscinoderma sp. The structures of these compounds were confirmed by nuclear magnetic resonance (1H and 13C NMR) spectroscopy, and their antiplasmodial activities were determined against the chloroquine-resistant Dd2 strain of Plasmodium falciparum. The epidioxy steroids 3–6 all showed moderate to weak antiplasmodial activity, with IC50 values of 2.7 μM for (24S)-5α,8α-epidioxy-24-methylcholesta-6-en-3β-ol (3), 11.6 μM for 5α,8α-epidioxycholesta-6,24(28)-dien-3β-o1 (4), 2.33 μM for 5α,8α-epidioxy-24-methylcholesta-6,9(11)-24(28)-trien-3β-ol (5), and between 12 and 24 μM for 5α,8α-epidioxycholesta-6-en-3β-ol (6). In contrast, halisulfate 2 (1) was inactive, and halisulfate 1 (2) had an of IC50 value of about 24 μM.

中文翻译：

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来自海洋海绵 Coscinodema sp. 的抗疟原虫成分的分离和表征。

摘要 从海洋海绵 Coscinodema sp. 中分离出六种已知化合物，即两种卤代硫酸盐 1 和 2 以及四种表二氧基甾醇 3-6。这些化合物的结构通过核磁共振（1H 和 13C NMR）光谱证实，并且它们的抗疟原虫活性被确定为抗氯喹抗性 Dd2 恶性疟原​​虫菌株。表二氧基类固醇 3-6 均显示出中度至弱的抗疟原虫活性，(24S)-5α,8α-epidioxy-24-methylcholesta-6-en-3β-ol (3) 的 IC50 值为 2.7 μM，5α 的 IC50 值为 11.6 μM ,8α-epidioxycholesta-6,24(28)-dien-3β-o1 (4), 2.33 μM for 5α,8α-epidioxy-24-methylcholesta-6,9(11)-24(28)-trien-3β- ol (5)，5α,8α-epidioxycholesta-6-en-3β-ol (6) 介于 12 和 24 μM 之间。相比之下，halisulfate 2 (1) 是无活性的，halisulfate 1 (2) 的 IC50 值约为 24 μM。