MDL 105519 is primarily utilized in neuroscience research due to its role as a selective and potent antagonist of the glycine site on the NMDA receptor. This makes it a valuable tool for studying the function and modulation of NMDA receptors, which are critical for synaptic plasticity, learning, and memory. Researchers use it to investigate the mechanisms underlying neurological disorders such as schizophrenia, epilepsy, and neurodegenerative diseases. Additionally, it helps in exploring the therapeutic potential of targeting the glycine binding site for drug development in conditions involving NMDA receptor dysfunction. Its application extends to understanding excitotoxicity and neuroprotection, providing insights into cellular responses to injury or stress in the central nervous system.