[{"from": "human", "value": "Use the given information to create a molecule that fulfills the desired purpose. The molecule is a dark reddish-brown liquid. Colloidal suspension of an iron-dextran complex in water. pH 5.2-6.5."}, {"from": "gpt", "value": "[O][S][=Branch1][C][=O][=Branch1][C][=O][O].[Fe]"}]