Potent, selective inverse agonist for the benzodiazepine site of GABAA receptors containing the α5 subunit (Ki = 0.45 nM). Displays 50-100-fold selectivity over GABAA receptors containing α1, α2, α3 or α6 subunits in combination with β3 and γ2. Enhances LTP in a mouse hippocampal slice model and increases spatial learning, without displaying proconvulsant activity. Purity 98%. MW (observed): 341.37