[{"from": "human", "value": "Create a molecule that satisfies the conditions outlined in the description. The molecule is a methyl ketone that is nonane in which the methylene hydrogens at position 2 are replaced by an oxo group. It has a role as a plant metabolite. It derives from a hydride of a nonane."}, {"from": "gpt", "value": "[C][C][C][C][C][C][C][C][=Branch1][C][=O][C]"}]