L-685,458 is primarily used in biochemical research as a potent and selective inhibitor of gamma-secretase, an enzyme involved in the processing of amyloid precursor protein (APP). This compound is particularly valuable in studies aimed at understanding the pathogenesis of Alzheimer's disease, as it helps researchers investigate the role of gamma-secretase in the production of amyloid-beta peptides, which are implicated in the formation of amyloid plaques in the brain. By inhibiting gamma-secretase, L-685,458 allows scientists to explore potential therapeutic strategies for Alzheimer's and related neurodegenerative disorders. Additionally, it serves as a tool compound in pharmacological studies to dissect the complex mechanisms of gamma-secretase and its substrates.