BSPP is a compound used in scientific research which acts as a positive allosteric modulator at the GABA<sub>B</sub> receptor. It has a synergistic effect with GABA<sub>B</sub> agonists such as baclofen at GABA<sub>B</sub> autoreceptors but not heteroreceptors, suggesting it may be useful for distinguishing between these GABA<sub>B</sub> receptor subtypes.