You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
5-chloro-3,3-dimethyl-2-[5-[(2-propanoyl-2-azaspiro[3.3]heptan-6-yl)methyl]pyridin-3-yl]isoindol-1-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C25H28ClN3O2
assistant