You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-(4-cyclobutylpiperazin-1-yl)-2-[4-[4-[3-(dimethylamino)phenyl]phenyl]piperazin-1-yl]ethanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C28H39N5O
assistant