You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named [2-(3,5-dimethylanilino)pyrimidin-4-yl]-(4-pyrimidin-2-ylpiperazin-1-yl)methanone is given. What is its corresponding molecular formula?
user
C21H23N7O
assistant