[Problem] Provided is a compound which is useful as a dopamine D1 receptor positive allosteric modulator (D1 PAM). [Means for Solution] The present inventors have studied a compound which has a positive allosteric modulating action (PAM action) on a dopamine D1 receptor and which can be used as an active ingredient of a pharmaceutical composition for preventing and/or treating cognitive impairment, schizophrenia negative symptom, CIAS, Parkinson's disease, Alzheimer's disease, Huntington's disease, depression, ADHD, drug dependency, or the like. Thus, they have found that the imidazodiazepine compound of the present invention has a PAM action on a dopamine D1 receptor, and thereby completed the present invention. The imidazodiazepine compound of the present invention has a PAM action on a dopamine D1 receptor, and is expected to be an agent for preventing and/or treating cognitive impairment, schizophrenia negative symptom, CIAS, Parkinson's disease, Alzheimer's disease, Huntington's disease, depression, ADHD, drug dependency, or the like.
