You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[2-[4-(3-chloro-2,2-dimethylpropanoyl)piperazin-1-yl]ethyl]-3-(4-chlorophenyl)-1-[(6,6-dimethyl-2-bicyclo[3.1.1]hept-2-enyl)methyl]urea is the IUPAC name of a molecule. Please give its molecular formula.
user
C28H40Cl2N4O2
assistant