You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name methyl N-[1-[4-(2,5-dichlorophenyl)sulfonylpiperazin-1-yl]-4-methyl-1-oxopentan-2-yl]carbamate into its molecular formula.
user
C18H25Cl2N3O5S
assistant