A positive allosteric modulator of mGluR5 (EC50s = 0.17 and 0.23 μM for potentiation of glutamate activity in HEK293 cells expressing rat mGluR5 and primary astrocyte cultures, respectively); selective for mGluR5 over rat mGluR1 and human mGluR1 and mGluR4 at 10 μM; decreases the conditioned avoidance response, apomorphine-induced climbing, as well as PCP-, apomorphine-, and amphetamine-induced locomotor activity in rats in a dose-dependent manner; improves recall in a novel object recognition test and reduces impulsivity in the 5CSRTT from 0.1-50 mg/kg; enhances reversal learning in mice in the Morris water maze test,