A new isochromeno[4,3-b]chromen-7(5H)-one derivative, 8-hydroxy-3,10-dimethoxyisochromeno [4,3-b]chromen-7(5H)-one (1), has been isolated from the aerial part of Filipendula kiraishiensis, together with seven known compounds. The structure of the new compound 1 was determined through spectroscopic and MS analyses. Among the isolates, luteolin (2), rutin (3), quercetin (4), and isoquercitrin (5) showed potent inhibition with IC50 values of 24.2 ± 1.2, 18.6 ± 1.3, 10.2 ± 0.5, and 12.2 ± 1.0 μM, respectively, against LPS-induced NO generation. In addition, 8-hydroxy-3,10-dimethoxyisochromeno[4,3-b]chromen-7(5H)-one (1) exhibited anti-Dengue virus activities with IC50 value of 22.4 ± 1.6 μM against Dengue virus serotype 2 strain PL046.

中文翻译：

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一种新的 Isochromeno[4,3-b]Chromen-7(5H)-Filipendula kiraishiensis 的一种衍生物和生物活性成分

一种新的异色烯 [4,3-b] chromen-7(5H)-one 衍生物，8-羟基-3,10-二甲氧基异色烯 [4,3-b]chromen-7(5H)-one (1)，已被从 Filipendula kiraishiensis 的地上部分分离出来，连同七种已知化合物。通过光谱和质谱分析确定了新化合物 1 的结构。在分离株中，木犀草素 (2)、芦丁 (3)、槲皮素 (4) 和异槲皮苷 (5) 显示出有效的抑制作用，IC50 值分别为 24.2 ± 1.2、18.6 ± 1.3、10.2 ± 0.5 和 12.2 ± 1.0 μM , 对抗 LPS 诱导的 NO 生成。此外，8-羟基-3,10-二甲氧基异色基[4,3-b]色烯-7(5H)-one (1) 表现出抗登革热病毒活性，对登革热病毒血清型 2 株的 IC50 值为 22.4 ± 1.6 μM PL046。