Two unique polyketides, pleosporalesones A–B (1–2), bearing an unusual 6/6/7/6 tetracyclic ring system consisting of a chromone ring and a benzoannulated cycloheptanone ring, were isolated from the solid cultures of Pleosporales sp.. The chemical structures were elucidated by analyses of their extensive spectroscopic data, including 1D/2D NMR, ORD, CD and HR-ESI-MS, and the absolute configurations were established by comparison of their experimental circular dichroism data with those calculated. A plausible biosynthetic pathway for pleosporalesones A–B was proposed.

中文翻译：

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Pleosporalesones A–B，从Pleosporales sp。分离的两个独特的聚酮化合物。

两个独特的聚酮化合物，pleosporalesones A-B（1 - 2），轴承由色酮环和环庚酮benzoannulated环的一个不寻常的6/6/7/6四环系统，是从的固体培养物中分离Pleosporales SP。该通过分析其广泛的光谱数据（包括1D / 2D NMR，ORD，CD和HR-ESI-MS），阐明了其化学结构，并通过比较了其实验圆二色性数据与计算得出的数据，确定了其绝对构型。提出了一种用于胸膜孢菌A–B的合理的生物合成途径。