A new member of the dunaimycin family, dunaimycin C3 (2), was isolated from a fermented broth of Streptomyces sp. RAN389. The molecular formula of 2 was established as C₄₂H₇₀O₁₀ by high-resolution FAB-MS, and the structure was elucidated by NMR spectroscopic analyses. Dunaimycin C3 inhibited the expression of the molecular chaperone GRP78 in HT1080 G-L cells in the presence of 10 mM of 2-deoxyglucose with an IC₅₀ of 8.4 nM.

中文翻译：

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杜奈霉素C3，一种来自链霉菌属的新GRP78下调剂。RAN389。

杜奈霉素家族的一个新成员，杜奈霉素C3（2），是从链霉菌属的发酵液中分离得到的。RAN389。通过高分辨率FAB-MS将2的分子式确定为C ₄₂ H ₇₀ O ₁₀，并通过NMR光谱分析阐明其结构。在10 mM的2-脱氧葡萄糖存在下，杜奈霉素C3抑制HT1080 GL细胞中分子伴侣GRP78的表达，IC ₅₀为8.4 nM。