A new anthracycline-type metabolite, designated as tetracenoquinocin A (1), was isolated from the fermentation broth of Streptomyces sp. NEAU-L3. Its structure was determined on the basis of spectroscopic analysis, including 1D and 2D NMR techniques as well as ESI-MS and comparison with data from the literature. Compound 1 showed potent cytotoxic activity against three cancer cell lines (HepG2, A549, HCT-116) with IC₅₀ values of 5.57, 24.30 and 20.82 μM, respectively.

中文翻译：

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链霉菌属的一种新的蒽环类代谢物。NEAU-L3。

从Streptomyces sp。的发酵液中分离出一种新的蒽环型代谢物，称为四菌灵喹诺酮A（1）。NEAU-L3。它的结构是在光谱分析的基础上确定的，包括1D和2D NMR技术以及ESI-MS，并与文献数据进行了比较。化合物1对三种癌细胞系（HepG2，A549，HCT-116）表现出强大的细胞毒活性，IC ₅₀值分别为5.57、24.30和20.82μM。