Four previously undescribed meroterpenoids, amestolkolides A-D, along with three known compounds were isolated from the mangrove endophytic fungus Talaromyces amestolkiae YX1 cultured on wheat solid-substrate medium culture. Their structures were elucidated by a combination of spectroscopic analyses. The absolute configurations of amestolkolides B and C, and purpurogenolide E were determined by single-crystal X-ray diffraction using Cu Kα radiation, and those of amestolkolides A and D were elucidated on the basis of experimental and calculated electronic circular dichroism spectra. The absolute configuration of amestolkolides A-D, and purpurogenolide E (9R) at C-9 was different from that of analogues (9S) in references, so that their plausible and distinct biosynthetic pathways were proposed. Amestolkolide B showed strong anti-inflammatory activity in vitro by inhibiting nitric oxide (NO) production in lipopolysaccharide activated in RAW264.7 cells with IC50 value of 1.6 ± 0.1 μM.

中文翻译：

---

来自红树林内生真菌 Talaromyces amestolkiae YX1 的抗炎类萜

从在小麦固体基质培养基上培养的红树林内生真菌 Talaromyces amestolkiae YX1 中分离出四种以前未描述的类萜类物质，amestolkolides AD，以及三种已知的化合物。通过光谱分析的组合阐明了它们的结构。amestolkolides B 和 C 以及 purpurogenolide E 的绝对构型通过使用 Cu Kα 辐射的单晶 X 射线衍射确定，并且 amestolkolides A 和 D 的绝对构型基于实验和计算的电子圆二色光谱阐明。amestolkolides AD 和 purpurogenolide E (9R) 在 C-9 处的绝对构型与参考文献中的类似物 (9S) 不同，因此提出了它们合理且独特的生物合成途径。