[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is a medium-chain fatty acid anion that is the conjugate base of undecanoic acid; used in tandem with testosterone cation in the treatment of male hypogonadism. Major species at pH 7.3. It has a role as a human metabolite. It is a medium-chain fatty acid anion and a straight-chain saturated fatty acid anion. It is a conjugate base of an undecanoic acid."}, {"from": "gpt", "value": "[C][C][C][C][C][C][C][C][C][C][C][=Branch1][C][=O][O-1]"}]