[{"from": "human", "value": "Could you give me a brief overview of this molecule? [C][C][O][P][=Branch1][C][=O][Branch2][Ring1][C][C@H1][Branch1][C][C][N][C][=Branch1][C][=O][N][Branch1][Ring2][C][C][Cl][N][=O][O][C][C]"}, {"from": "gpt", "value": "The molecule is a diethyl (1-{[(2-chloroethyl)(nitroso)carbamoyl]amino}ethyl)phosphonate that has R configuration. It is an enantiomer of a (S)-fotemustine."}]