[{"from": "human", "value": "Generate a molecule based on the given description. The molecule is an unbranched fifteen-carbon alkene with one double bond between C-1 and C-2. It has a role as a mammalian metabolite."}, {"from": "gpt", "value": "[C][C][C][C][C][C][C][C][C][C][C][C][C][C][=C]"}]