[{"from": "human", "value": "Provide a brief overview of this molecule. [C][C@H1][Branch1][=Branch2][C][C][C][C][Branch1][C][C][C][C@H1][C][C][C@@H1][C@@][Ring1][Branch1][Branch2][Branch1][C][C][C][C@H1][C@H1][Ring1][=Branch1][C][C][=C][C@@][Ring1][=Branch1][Branch2][Ring2][C][C][C][C@@H1][Branch1][Ring2][C][Ring1][=Branch1][O][C][=Branch1][C][=O][C][C][=C][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][N][Branch1][Ring2][C][C][Cl][C][C][Cl][C][C]"}, {"from": "gpt", "value": "The molecule is a steroidal nitrogen mustard with antineoplastic and mutagenic activities. After attachment to cell-surface steroid receptors and uptake, phenesterin enters the nucleus where it alkylates macromolecules, resulting in decreased cell proliferation. (NCI04)"}]