Description:Human intestinal microbiota exert significant influences on host physiology through bioactive molecules. Indole derivatives, a diverse class of organic compounds arising from microbial-mediated tryptophan metabolism, play pivotal roles in maintaining metabolic homeostasis and disease progression. The characteristic aromatic heterocycle substructure shared in various indole derivatives is intrinsically associated with the activation of aryl hydrocarbon receptor (AhR), suggesting a potential structure-activity relationship (SAR) which remains underexplored. In the present study, we developed a structure-to-activity relationship metabolomics (StAR-MS) pipeline that aims at elucidating the SAR information embedded within metabolomics data, further applied it to identify novel gut microbiome-derived, indole-like derivatives with potential AhR agonistic activity. A total of 22 metabolites exhibiting activity-related substructures were identified, four of which were characterized for the first time.