LDN-57444 is primarily used in biochemical research as a selective inhibitor of ubiquitin C-terminal hydrolase L1 (UCH-L1). This enzyme plays a crucial role in the ubiquitin-proteasome pathway, which is involved in protein degradation and regulation. By inhibiting UCH-L1, researchers can study its function and its impact on cellular processes, particularly in neurodegenerative diseases like Parkinson's, where UCH-L1 has been implicated. Additionally, LDN-57444 is utilized in studies exploring the role of ubiquitination in cancer progression, as altered ubiquitin pathways are often associated with tumor development. Its application helps in understanding disease mechanisms and in the development of potential therapeutic strategies.