LCL521 dihydrochloride is a potent and selective inhibitor of monoamine oxidase B (MAO-B), primarily utilized in research settings within molecular biology and pharmacology. It serves as a tool compound to study mechanisms of specific biological pathways, particularly MAO-B-mediated neurotransmitter metabolism in neurodegenerative disorders such as Parkinson's disease and Alzheimer's. Researchers employ it to investigate cellular processes, evaluate effects on disease models, and assess enzyme inhibition. Its use in high-throughput screening assays aids in identifying therapeutic targets. Additionally, it is applied in preclinical studies to evaluate pharmacokinetics and pharmacodynamics, providing insights into efficacy and safety.