[{"from": "human", "value": "Provide a description of this molecule. [C][C][C][C][Branch1][Branch1][C][C][Ring1][=Branch1][N][C][=Branch1][C][=O][N][Branch1][Ring2][C][C][Cl][N][=O]"}, {"from": "gpt", "value": "The molecule is a nitrosourea with antineoplastic activity. Lomustine alkylates and crosslinks DNA, thereby inhibiting DNA and RNA synthesis.  This agent also carbamoylates DNA and proteins, resulting in inhibition of DNA and RNA synthesis and disruption of RNA processing.  Lomustine is lipophilic and crosses the blood-brain barrier. (NCI04)"}]