[{"from": "human", "value": "Generate a molecule based on this description. The molecule is a sphingomyelin d18:1 in which the acyl group specified is heneicosanoyl. It has a role as a mouse metabolite. It is functionally related to a henicosanoic acid."}, {"from": "gpt", "value": "[C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][=Branch1][C][=O][N][C@@H1][Branch2][Ring1][Branch1][C][O][P][=Branch1][C][=O][Branch1][C][O-1][O][C][C][N+1][Branch1][C][C][Branch1][C][C][C][C@@H1][Branch1][S][/C][=C][/C][C][C][C][C][C][C][C][C][C][C][C][C][O]"}]