[{"from": "human", "value": "Provide a brief overview of this molecule. [C][Branch1][=Branch1][C][=Branch1][C][=O][O][C][Branch1][#Branch1][C][C][=Branch1][C][=O][O][Branch1][=Branch1][C][=Branch1][C][=O][O][O]"}, {"from": "gpt", "value": "The molecule is a tricarboxylic acid found in citrus fruits. Citric acid is used as an excipient in pharmaceutical preparations due to its antioxidant properties.  It maintains stability of active ingredients and is used as a preservative. It is also used as an acidulant to control pH and acts as an anticoagulant by chelating calcium in blood."}]