| abstract |
Disclosed are compounds of formula (I), or the pharmaceutically acceptable non-toxic salts thereof where R1-R4 and A are defined herein, which compounds are highly selective agonists, antagonists or inverse agonists for GABAa brain receptors or prodrugs of agonists, antagonists or inverse agonists for GABAa brain receptors and are, therefore, useful in the diagnosis and treatment of anxiety, Down Syndrome, depression, sleep, cognitive and seizure disorders, overdose with benzodiazepine drugs and for enhancement of altertness. |