Abstract

Two new canthin-6-one alkaloids, 4,9-dimethoxy-5-hydroxycanthin-6-one (1) and 9-methoxy-(R/S)-5-(1-hydroxyethyl)-canthin-6-one (2), together with fifteen known ones were isolated from the roots of Thailand Eurycoma longifolia Jack. Among the known canthin-6-one alkaloids, compounds 9 and 16 were isolated from the Eurycoma genus for the first time. Meanwhile, the nitric oxide (NO) inhibitory activities of all isolates were examined in lipopolysaccharide (LPS)-stimulated RAW264.7 cells at 50 µM. Moreover, a dose-dependent experiment was conducted for active compounds 1, 2, 4, 6, 7, 10, 12–17 at the concentration of 10, 25, and 50 µM, respectively. Consequently, compounds 1, 4, 6, 7, 12, 14, 15, as well as 17 were found to inhibit NO release from RAW264.7 cells in a dose-dependent manner.

Graphic abstract

Two new canthin-6-one alkaloids, 4,9-dimethoxy-5-hydroxycanthin-6-one (1) and 9-methoxy-(R/S)-5-(1-hydroxyethyl)-canthin-6-one (2), together with fifteen known ones were isolated from the roots of Thailand Eurycoma longifolia Jack. Among them, 1, 4, 6, 7, 12, 14, 15, as well as 17 were found to inhibit NO release from RAW264.7 cells in a dose-dependent manner at the concentration of 10, 25, and 50 µM.

中文翻译：

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来自泰国Eurycoma longifolia Jack的根的抗炎canthin-6-one生物碱。

摘要

两个新的canthin-6-one生物碱4,9-二甲氧基-5-羟基canthin-6-一（1）和9-甲氧基-（R / S）-5-（1-羟乙基）-canthin-6-one（2），与15个已知的一起从泰国Eurycoma longifolia Jack的根中分离出来。在已知的canthin-6-one生物碱中，化合物9和16首次从Eurycoma属中分离出来。同时，在脂多糖（LPS）刺激的RAW264.7细胞中以50 µM检测了所有分离株的一氧化氮（NO）抑制活性。此外，剂量依赖性实验对活性化合物进行1，2，4，6，7，10，12 - 17在10，25的浓度，和50μM，分别。因此，化合物1，4，6，7，12，14，15，以及17被发现抑制以剂量依赖的方式从RAW264.7细胞的NO释放。

图形摘要

两个新的canthin-6-one生物碱4,9-二甲氧基-5-羟基canthin-6-一（1）和9-甲氧基-（R / S）-5-（1-羟乙基）-canthin-6-one（ 2）从泰国Eurycoma longifolia Jack的根中分离出15种已知的植物。其中1、4、6、7、12、14、15和17被发现在浓度为10、25和50 µM时以剂量依赖的方式抑制NO从RAW264.7细胞释放。