Two highly oxygenated nor-clerodane diterpenoids, crocleropenes A and B (1 and 2), together with four known compounds (3–6) were isolated from the leaves and twigs of Croton caudatus. Their structures were elucidated by combination of extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. 1 and 2 represent the first examples of nor-clerodane-3,5(10)-diene diterpenoids. Compounds 1 and 2 exhibited weak cytotoxicity in vitro against MCF-7 cancer cells with IC₅₀ values of 35.8 and 40.2 μM, respectively.

中文翻译：

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来自巴豆科鱼的两种高度氧化的去甲环烷烃二萜。

两个高度氧化也不-clerodane二萜类化合物，crocleropenes A和B（1和2），具有四个已知化合物（一起3-6）从的树叶和树枝分离巴豆尾穗。通过广泛的光谱分析和电子圆二色性（ECD）计算的组合，阐明了它们的结构。1和2表示的第一实施例，也不-clerodane -3,5（10） -二烯二萜类化合物。化合物1和2在体外对具有IC _50的MCF-7癌细胞表现出微弱的细胞毒性 分别为35.8和40.2μM。