The reaction mechanism of the intramolecular [2 + 2] cycloaddition from a jatrophane precursor to the gaditanane skeleton, an unprecedented 5/6/4/6-fused tetracyclic ring framework recently isolated from Euphorbia spp., was studied using the bond reactivity indices approach. Furthermore, six diterpenoids, including three undescribed jatrophanes isolated from E. gaditana Coss, were described. The structures of these compounds were deduced by a combination of 2D NMR spectroscopy and ECD data analysis.

中文翻译：

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麻风树骨架二萜类化合物[2+2]环加成反应的键反应性指数方法分析为四环gaditanone

使用键反应性指数方法研究了从麻风树前体到 Gaditanane 骨架的分子内 [2 + 2] 环加成反应机制，这是一种前所未有的 5/6/4/6 稠合四环骨架，最近从大戟属植物中分离出来。 . 此外，还描述了六种二萜，包括从 E. gaditana Coss 中分离出的三种未描述的麻风树。这些化合物的结构是通过 2D NMR 光谱和 ECD 数据分析的组合推导出来的。