AbstractTracazolate (ICI 136,753; 4‐butylamino‐1‐ethyl‐6‐methyl‐1H‐pyrazolo [3,4‐b] pyridine‐5‐carboxylic acid ethyl ester) exhibited dose‐related anticonflict activity in mice, rats, and squirrel monkeys. The potency of tracazolate appears to be one‐quarter to one‐half that of chlordiazepoxide, and their durations of activity are similar in rats. No tolerance to the anticonflict activity of either chlordiazepoxide or tracazolate was evident following 12 consecutive days of treatment. Tracazolate exhibits a much greater separation between sedative and therapeutic doses than does chlordiazepoxide; thus, it is predicted that tracazolate will not be sedative at anxiolytic doses in man. Furthermore, based upon studies in rodents, tracazolate should be much less likely than the benzodiazepines to potentiate the actions of barbiturates and ethanol in man. Although tracazolate is an anticonvulsant in rodents, it is considerably less potent in this respect than chlordiazepoxide. In contrast to benzodiazepine anxiolytics, tracazolate enhances the binding of 3H‐benzodiazepines to their binding sites in brain. Consistent with this finding, tracazolate potentiated both the anticonvulsant and anxiolytic effects of chlordiazepoxide in rodents. Although the benzodiazepine antagonists (RO 15‐1788 and CGS 8216) clearly antagonize the anticonflict activity of chlordiazepoxide, the activity of tracazolate was not significantly altered by either antagonist. Both chlordiazepoxide and tracazolate significantly enhanced 3H‐γ‐aminobutyric acid (GABA) binding. These results suggest that tracazolate is a novel psychoactive agent that should be a useful anxiolytic drug in man.