*Review* **Sulfur-Containing Compounds from Endophytic Fungi: Sources, Structures and Bioactivities**

**Yaqin Fan 1,†, Zhiheng Ma 1,†, Yan Zhang <sup>1</sup> , Yufei Wang <sup>2</sup> , Yousong Ding <sup>3</sup> , Cong Wang 2,\* and Shugeng Cao 4,\***


**Abstract:** Endophytic fungi have attracted increasing attention as an under-explored source for the discovery and development of structurally and functionally diverse secondary metabolites. These microorganisms colonize their hosts, primarily plants, and demonstrate diverse ecological distribution. Among endophytic fungal natural products, sulfur-containing compounds feature one or more sulfur atoms and possess a range of bioactivities, e.g., cytotoxicity and antimicrobial activities. These natural products mainly belong to the classes of polyketides, nonribosomal peptides, terpenoids, and hybrids. Here, we reviewed the fungal producers, plant sources, chemical structures, and bioactivities of 143 new sulfur-containing compounds that were reported from 1985 to March 2022.

**Keywords:** sulfur; plant endophyte; endophytic fungi
