Potent, non-substrate inhibitor of EAAT2 (GLT-1) that displays > 44-fold selectivity over EAAT1 and EAAT3 (IC50 values are 85, 3787 and 5004 nM for EAAT2, EAAT3 and EAAT1 respectively). Exhibits no activity towards ionotropic and metabotropic glutamate receptors.