A new cytotoxic agent designated as 2-epi-anthracimycin (1) was isolated along with anthracimycin and anthracimycin B (2-demethylanthracimycin) from the culture broth of the marine-derived actinomycete Streptomyces sp. OPMA00631. The structure of 1 was elucidated based on spectroscopic analyses (1D and 2D NMR data and ROESY correlations). Compound 1 exhibited cytotoxicity against Jurkat cells with an IC50 value of 50.5 μM in 20 h. The effect of 1 on the cell cycle distribution of Jurkat cells was investigated. Compound 1 (7.80 μM) increased G1 phase cells from 51.1 to 62.0% and conversely, decreased G2 and M phase cells from 30.7 to 19.3 % in 20 h. At a higher concentration, 1 (250 μM) markedly increased subG1 phase cells (1.9% at 0 h to 16.5% at 20 h), while the proportion of G1 phase cells was maintained (62.3%). These results suggest that 1 exhibits cytotoxicity against Jurkat cells by arresting the cell cycle at the G1 phase.

中文翻译：

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2-表蒽霉素，一种新的细胞毒性剂，来自海洋放线菌链霉菌种。OPMA00631。

从海洋来源的放线菌链霉菌属菌种的培养液中分离出一种新的细胞毒剂，称为2-表蒽霉素（1）以及蒽霉素和蒽霉素B（2-脱甲基蒽霉素）。OPMA00631。基于光谱分析（1D和2D NMR数据以及ROESY相关性）阐明了1的结构。化合物1对Jurkat细胞显示出细胞毒性，在20小时内的IC50值为50.5μM。研究了1对Jurkat细胞的细胞周期分布的影响。化合物1（7.80μM）在20小时内将G1期细胞从51.1％增加到62.0％，相反，将G2和M期细胞从30.7％减少到19.3％。在较高浓度下，1个（250μM）显着增加了subG1期细胞（0小时时为1.9％，20小时时为16.5％），而G1期细胞的比例保持不变（62.3％）。