[{"from": "human", "value": "Provide a description of this molecule. [C][C][=N][C][=C][Branch1][Branch2][C][=Branch1][Ring2][=N][Ring1][=Branch1][N][C][N][C][=Branch1][C][=O][N][Branch1][Ring2][C][C][Cl][N][=O]"}, {"from": "gpt", "value": "The molecule is an organochlorine compound that is urea in which the two hydrogens on one of the amino groups are replaced by nitroso and 2-chloroethyl groups and one hydrogen from the other amino group is replaced by a 4-amino-2-methylpyrimidin-5-ylmethyl] group. An antineoplastic agent especially effective against malignant brain tumors. It has a role as an alkylating agent and an antineoplastic agent. It is an organochlorine compound, an aminopyrimidine and a member of N-nitrosoureas. It is a conjugate base of a nimustine(1+)."}]