You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-cyclopentyl-1-[4-[2-(dimethylamino)ethyl]-3,5-dimethylpiperazin-1-yl]propan-1-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H35N3O
assistant