Ae.gThis invention relates to benzodiazepine derivatives compositions comprising therapeutically effective amounts of those benzodiazepine derivatives and methods of using those derivatives or compositions in treating central nervous system (CNS) disorders with cognitive impairment that are responsive to agonists of a5 subunit containing GABA receptor . age related cognitive impairment Mild Cognitive Impairment (MCI) dementia Alzheimer s Disease(AD) prodromal AD post traumatic stress disorder (PTSD) schizophrenia and cancer therapy related cognitive impairment.