Eeyarestatin I is primarily used in biochemical and biomedical research due to its ability to inhibit endoplasmic reticulum-associated degradation (ERAD). This makes it a valuable tool for studying protein quality control mechanisms within cells. By blocking ERAD, it induces the accumulation of misfolded proteins, leading to endoplasmic reticulum stress, which can trigger apoptosis. This property is exploited in cancer research, where Eeyarestatin I has shown potential in promoting cell death in certain tumor cell lines. It is also used to investigate the unfolded protein response (UPR) pathway, offering insights into diseases linked to protein misfolding, such as neurodegenerative disorders and diabetes. Its role as a selective inhibitor helps researchers dissect the molecular components of ER stress pathways and evaluate therapeutic strategies targeting proteostasis.