Recently, a rare class of nonribosomal peptides (NRPs) bearing a unique Oxepine-Pyrimidinone-Ketopiperazine (OPK) scaffold has been exclusively isolated from fungal sources. Based on the number of rings and conjugation systems on the backbone, it can be further categorized into three types A, B, and C. These compounds have been applied to various bioassays, and some have exhibited promising bioactivities like antifungal activity against phytopathogenic fungi and transcriptional activation on liver X receptor α. This review summarizes all the research related to natural OPK NRPs, including their biological sources, chemical structures, bioassays, as well as proposed biosynthetic mechanisms from 1988 to March 2020. The taxonomy of the fungal sources and chirality-related issues of these products are also discussed.

中文翻译：

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Oxepine-Pyrimidinone-Ketopiperazine型非核糖体肽的综述。

最近，已从真菌来源中独家分离出一类罕见的带有独特奥塞平-嘧啶酮-酮戊哌嗪（OPK）支架的非核糖体肽（NRP）。根据主链上的环数和缀合系统的数量，可以将其进一步分为A，B和C三种类型。这些化合物已应用于各种生物测定中，其中一些已显示出令人鼓舞的生物活性，例如针对植物病原真菌的抗真菌活性和肝X受体α的转录激活。这篇综述总结了与天然OPK NRP相关的所有研究，包括其生物学来源，化学结构，生物测定以及从1988年至2020年3月提出的生物合成机制。这些产品的真菌来源分类和与手性相关的问题讨论过。