Bioactivity-guided isolation of Aspergillus ustus led to the discovery of five new drimane sesquiterpenes, named ustusal A, ustusolate F and G, and ustusoic acid A and B, 1–5 respectively. Structural elucidation of these fungal terpenes relied on 1D and 2D NMR techniques, high-resolution mass spectrometry, and chiroptical properties. Their relative configurations were determined by NMR methods, while the absolute configurations were established using comparative analyses of computed and experimental NMR chemical shifts and ECD spectra. The sesquiterpenes exhibited weak activity against the clinically relevant pathogens vancomycin-resistant Enterococcus faecium and multidrug-resistant Staphylococcus aureus; however, the activity of 5 was drastically enhanced when equal amounts of stromemycin (6), a known metabolite coisolated from the same fraction from A. ustus, was added.

中文翻译：

---

来自 Aspergillus ustus 的抗菌 Drimane 倍半萜

Aspergillus ustus 的生物活性引导分离导致发现了五种新的 drimane 倍半萜，分别命名为 ustusal A、ustusolate F 和 G，以及 ustusoic acid A 和 B，1 – 5。这些真菌萜烯的结构阐明依赖于一维和二维核磁共振技术、高分辨率质谱和手性光学特性。它们的相对构型是通过 NMR 方法确定的，而绝对构型是使用计算和实验 NMR 化学位移和 ECD 光谱的比较分析建立的。倍半萜烯对临床相关病原体万古霉素耐药粪肠球菌和多重耐药金黄色葡萄球菌的活性较弱; 然而，活性5时stromemycin的等量（被飞跃性地提高6），一种已知的代谢物从来自相同级分coisolated A. ustus，加入。