[{"from": "human", "value": "Provide a brief overview of this molecule. [C][N][Branch1][C][C][C][C][C][C@@][Branch2][Ring1][Ring1][C][=C][Branch1][Branch1][C][O][Ring1][Branch1][C][=C][Branch1][Branch1][C][=C][Ring1][Branch2][C][#N][C][=C][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][F].[C][=Branch1][C][=O][Branch1][=Branch1][C][=Branch1][C][=O][O][O]"}, {"from": "gpt", "value": "The molecule is the oxalate salt of escitalopram, a pure S-enantiomer of the racemic bicyclic phthalane derivative citalopram, with antidepressant activity. As a selective serotonin reuptake inhibitor (SSRI), escitalopram blocks the reuptake of serotonin by neurons in the central nervous system (CNS), thereby potentiating CNS serotonergic activity."}]