New polycyclic tetramate macrolactams, Umezawamides A (1) and B (2) were isolated from a combined-culture of Umezawaea sp. RD066910 and mycolic-acid containing bacterium Tsukamurella pulmonis TP-B0596. Their planar structures and partial stereochemistries were determined based on the spectroscopic analysis, MMFF conformational search, and ECD calculations. Umezawamides are the first secondary metabolites isolated from the genus Umezawaea and they exhibited cytotoxicities to P388 murine leukemia cells. Furthermore, umezawamide A (1) showed growth inhibitory activity against Candida albicans.

中文翻译：

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Umezawamides，从Umezawaea sp。的联合培养物中分离得到的新的生物活性多环四酸酯大内酰胺。和含有霉菌酸的细菌。

从Umezawaea sp。的组合培养物中分离出新的多环四酸酯大内酰胺，Umezawamides A（1）和B（2）。RD066910和含霉菌酸的肺炎细菌Tsukamurella TP-B0596。它们的平面结构和部分立体化学是根据光谱分析，MMFF构象搜索和ECD计算确定的。Umezawamides是从Umezawaea属中分离出来的第一个次级代谢产物，对P388鼠白血病细胞表现出细胞毒性。此外，umezawamide A（1）对白色念珠菌具有生长抑制活性。