A new curromycin-related compound, neocurromycin A (2), was isolated from the fermented broth of Streptomyces sp. RAI364. The molecular formula of 2 was established as C₃₅H₄₄N₄O₇ by ESI–MS and the structure was elucidated by NMR spectroscopic analyses. Neocurromycin A showed selective cytotoxicity against MKN45 human gastric cancer cells in a nutrient-deprived medium with an IC₅₀ of 380 nM and 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 1.7 µM.

中文翻译：

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Neocurromycin A，一种来自链霉菌属的新GRP78下调剂。RAI364。

从链霉菌（Streptomyces sp）的发酵液中分离到一种新的与霉素相关的化合物新霉素A（2）。RAI364。通过ESI-MS建立2的分子式为C ₃₅ H ₄₄ N ₄ O ₇，并通过NMR光谱分析阐明其结构。新卡霉素A在营养缺乏的培养基中对MKN45人胃癌细胞具有选择性的细胞毒性，IC ₅₀为380 nM，并在10 mM 2-脱氧葡萄糖存在下抑制HT1080 GL细胞中分子伴侣GRP78的表达。1.7 µM中的₅₀。