An allosteric antagonist of NTS1 (Kd = 3.4 nM); inhibits neurotensin binding to brain tissue from guinea pig, newborn mouse, newborn human, and adult human as well as rat mesencephalic cells and HT-29 cells (IC50s = 0.99-30.3 nM); blocks neurotensin induced intracellular calcium mobilization in HT-29 cells (Ki = 7.4 nM); reduces tumor volume and cell proliferation in an NCI-H209 mouse xenograft model (10 μg per day); reduces contralateral turning induced by neurotensin administration in mice by 85% (80 μg/kg, p.o.); delays sensitization to the locomotor activating effects of cocaine in rats when administered prior to cocaine delivery and not concomitantly