Thiamet G is primarily used in biomedical research to study the role of O-GlcNAc modification in cellular processes. It acts as a potent and selective inhibitor of O-GlcNAcase (OGA), the enzyme responsible for removing O-GlcNAc groups from proteins. By inhibiting OGA, Thiamet G increases the levels of O-GlcNAc-modified proteins, allowing researchers to investigate how this post-translational modification affects signaling pathways, gene expression, and cell function. It is widely applied in studies related to neurodegenerative diseases, particularly tauopathies such as Alzheimer’s disease. Elevated O-GlcNAcylation via Thiamet G has been shown to reduce the aggregation of hyperphosphorylated tau proteins, a hallmark of Alzheimer’s pathology, making it a valuable tool for exploring potential therapeutic strategies. Thiamet G is also used in research on diabetes, cardiovascular diseases, and cancer, where O-GlcNAc cycling plays a regulatory role in stress response, metabolism, and cell survival. Due to its cell permeability and selectivity, it is suitable for both in vitro and in vivo experiments, helping to elucidate the physiological and pathological roles of O-GlcNAc signaling.