You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[2-butoxy-4-(diethylamino)phenyl]-6-(dimethylamino)-3-(2-ethyl-1-octylindol-3-yl)-2-benzofuran-1-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C42H57N3O3
assistant