You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-(2,3-dihydro-1-benzofuran-5-yl)-2-(dimethylamino)ethyl]-2-(2-methoxyphenoxy)acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H26N2O4
assistant