SL 75212 HCl is primarily used in research settings as a selective antagonist for the 5-HT1A receptor. Its application is significant in neuroscience studies, particularly in understanding the role of serotonin receptors in various physiological and behavioral processes. Researchers utilize it to investigate the mechanisms underlying anxiety, depression, and other mood disorders, as well as to explore potential therapeutic targets. Additionally, it aids in studying the interaction between serotonin pathways and other neurotransmitter systems, contributing to advancements in psychopharmacology and drug development.