Bioassay-guided isolation of the aerial part of Scutellaria barbata yielded three new neo-clerodane diterpenoids scutebatas P–R (1–3), together with two known ones: scutebata E (4) and scutebarbatine B (5). The chemical structures of the isolated compounds were elucidated by spectroscopic methods (NMR and MS) and by comparison with the spectroscopic data reported in the literature. All compounds except 3 showed weak cytotoxicity with IC₅₀ values ranging from 35.11 to 42.73 μM against K562 cell lines, and compounds 1, 2, and 5 also displayed weak activities against HL60 cell lines.

中文翻译：

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生物测定指导从半枝莲中分离出新环戊烷二萜。

的地上部分的生物测定引导的隔离半枝莲产生三个新的新克罗二萜scutebatas P-R（1 - 3 scutebata E（：具有两个公知的物质，一起）4）和scutebarbatine B（5）。分离的化合物的化学结构通过光谱方法（NMR和MS）进行了阐明，并与文献中报道的光谱数据进行了比较。除了所有化合物3显示出弱的细胞毒性与IC _50个值范围从35.11到42.73μM对K562细胞系中，和化合物1，2，和5也显示针对HL60细胞系弱活性。