L-742001 hydrochloride is primarily utilized in research settings for its role as a selective antagonist of the NK1 receptor, which is involved in the regulation of various physiological processes. It is commonly employed in studies focusing on the central nervous system, particularly in understanding the mechanisms of pain, anxiety, and depression. By blocking the NK1 receptor, it helps researchers investigate the receptor's role in these conditions and assess the potential therapeutic effects of NK1 receptor antagonism. Additionally, it is used in preclinical studies to explore its effects on neurotransmitter release and its implications in neuroinflammatory processes. This compound serves as a valuable tool in pharmacological and neurological research, aiding in the development of targeted therapies for neurological and psychiatric disorders.