You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[3-(1,3-benzodioxol-5-ylmethoxy)-2-hydroxypropyl]-4-thiophen-2-ylphthalazin-1-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C23H20N2O5S
assistant