Used as a selective inhibitor of nitric oxide synthase (NOS), particularly targeting neuronal NOS (nNOS). It is applied in research to study the role of nitric oxide in various physiological and pathological processes, such as neurotransmission, blood flow regulation, and inflammation. This compound helps in understanding the specific contributions of nNOS in neurological disorders, cardiovascular diseases, and other conditions where nitric oxide signaling is implicated. Its selective inhibition allows for precise experimental manipulation in biochemical and pharmacological studies.