Positive allosteric modulator of GABAB receptors. Increases the potency and efficacy of GABA at both native and recombinant GABAB receptors (EC50 values are 5.37 and 4.60μM respectively) and enhances the inhibitory effect of the agonist L-baclofen in cultured cortical neurons. Reduces operant self-administration of ethanol in alcohol-preferring rats following i.p. administration.