A new C13-norisoprenoid, chaenomelesterpenoid C (1), was isolated from the fruits of Chaenomeles sinensis (Dum.Cours.) Koehne together with a known compound, linarionoside C (2). The structure of compound 1 was determined by NMR and MS analysis. Meanwhile, the protective effects of the compounds were tested against corticosterone-induced damage in PC-12 cells using real time cellular analysis (RTCA). Compounds 1 and 2 significantly improved cell viability in corticosterone-induced damaged PC-12 cells with EC50 values of 21.0 and 49.1 μM, respectively.

中文翻译：

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木瓜果实中一种新的C13-去甲异戊二烯

从 Chaenomeles sinensis (Dum.Cours.) Koehne 的果实中分离出一种新的 C13-norisoprenoid，chaenomelesterpenoid C (1)，以及一种已知的化合物，linarionoside C (2)。化合物1的结构由NMR和MS分析确定。同时，使用实时细胞分析 (RTCA) 测试了化合物对 PC-12 细胞中皮质酮诱导的损伤的保护作用。化合物 1 和 2 显着提高了皮质酮诱导的受损 PC-12 细胞的细胞活力，EC50 值分别为 21.0 和 49.1 μM。