Ten new cephalotane-type diterpenoids, cephanolides A–J (1–10), and two known analogues were isolated and characterized from Cephalotaxus sinensis. Compounds 1–3 represent the first examples of A-ring-contracted cephalotane-type dinorditerpenoids, and compound 4 is an A-ring-contracted norditerpenoid. The biosynthetic pathways for compounds 1–4 are postulated with the coexisting cephalotane-type troponoids as the precursors. Compounds 11 and 12 showed significant cytotoxicities against a panel of tumor cell lines (A549, KB, HL-60, and HT-29) with IC₅₀ values ranging from 0.464 to 6.093 μM.

中文翻译：

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Cephanolides一个-J，从Cephalotane型二萜粗榧

十个新cephalotane型二萜，cephanolides甲-J（1 - 10），和两个已知类似物的分离和表征从粗榧。化合物1 - 3代表A-环收缩cephalotane型dinorditerpenoids的第一示例，并且化合物4是A环的收缩去甲二萜。的生物合成途径的化合物1 - 4被假定与共存cephalotane型troponoids作为前体。化合物11和12对具有IC _50的一组肿瘤细胞系（A549，KB，HL-60和HT-29）表现出显着的细胞毒性 值范围从0.464到6.093μM。