You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[1-(2-methoxyethyl)indol-4-yl]oxy-N-[(3-methylpyrazolidin-4-yl)methyl]acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H26N4O3
assistant