A phytochemical investigation of the stem barks of the Malaysian Croton oblongus Burm.f. (Syn. Croton laevifolius Blume) (Euphorbiaceae) yielded seven previously undescribed ent-neo-clerodane diterpenoids, laevifins A - G and the known crovatin (3). Structures were established by a combination of spectroscopic methods including HRESIMS, NMR spectroscopy and X-ray crystallography. The absolute configuration of crovatin and laevifins A-G was established by comparison of experimental ECD and theoretical TDDFT ECD calculated spectra. This is the first report on the occurrence of the sesquiterpenoid cryptomeridiol in a Croton species. In vitro cytotoxicity assays on laevifins A, B and G showed moderate activities against the MCF-7 cancer cell line (IC50 102, 115 and 106 μM, respectively) while β-amyrin and acetyl aleuritolic acid showed good anti-inflammatory activity on the LPS-induced NF-κB translocation inhibition in RAW 264.7 cells assay with IC50 values of 23.5 and 35.4 μg/mL, respectively.

中文翻译：

---

Laevifins A–G，来自巴豆树皮的 clerodane 二萜类化合物 Burm.f.

马来西亚巴豆 oblongus Burm.f. 茎皮的植物化学研究。（Syn. Croton laevifolius Blume）（大戟科）产生了七种以前未描述的 ent-neo-clerodane 二萜、laevifins A - G 和已知的 crovatin (3)。结构是通过光谱方法的组合建立的，包括 HRESIMS、NMR 光谱和 X 射线晶体学。通过比较实验 ECD 和理论 TDDFT ECD 计算光谱，确定了 crovatin 和 laevifins AG 的绝对构型。这是关于在巴豆属植物中出现倍半萜类隐孢子菌醇的第一份报告。laevifins A、B 和 G 的体外细胞毒性试验显示对 MCF-7 癌细胞系具有中等活性（IC50 102、115 和 106 μM，