[{"from": "human", "value": "Generate a molecule based on the given description. The molecule is a thiophene substituted at C-2 by a 4-ethylbenzoyl group. It has a role as an epitope. It is a member of thiophenes and an aromatic ketone."}, {"from": "gpt", "value": "[C][C][C][=C][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][C][=Branch1][C][=O][C][=C][C][=C][S][Ring1][Branch1]"}]