[{"from": "human", "value": "Provide a brief overview of this molecule. [C][=C][C][=Branch1][P][=C][C][=Branch1][Ring2][=C][Ring1][=Branch1][N][Branch1][Ring2][C][C][Cl][C][C][Cl][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O][N]"}, {"from": "gpt", "value": "The molecule is the meta form of the levo isomer melphalan, an alkylating nitrogen mustard with potential antineoplastic activity. Metamelfalan causes crosslinking of DNA, thereby preventing DNA replication and eventually cellular proliferation."}]