[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is a member of the class of propanals obtained by the reduction of the carboxylic group of lactic acid (2-hydroxypropanoic acid). It has a role as a mouse metabolite. It is a hydroxyaldehyde and a member of propanals."}, {"from": "gpt", "value": "[C][C][Branch1][Ring1][C][=O][O]"}]