S 14506 hydrochloride is a potent and selective agonist of the 5-HT1A serotonin receptor, with particular affinity for presynaptic autoreceptors. It is widely used in neuropharmacological research to study the modulation of serotonin release, neuroprotection, and anxiolytic effects. By desensitizing 5-HT1A autoreceptors upon chronic administration, it enhances serotonergic neurotransmission, making it valuable in preclinical models of depression, anxiety, schizophrenia, and cognitive impairments. Commonly applied in in vitro receptor binding assays, ex vivo brain slice preparations, and in vivo animal studies to evaluate receptor activation, downstream signaling, and behavioral outcomes.