[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is a member of the class of N-nitrosoureas that is urea in which one of the nitrogens is substituted by ethyl and nitroso groups. It has a role as an alkylating agent, a mutagen, a carcinogenic agent and a genotoxin. It is functionally related to a urea."}, {"from": "gpt", "value": "[C][C][N][Branch1][=Branch1][C][=Branch1][C][=O][N][N][=O]"}]