You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(2,3-dihydroindol-1-yl)-1-(2-methylphenyl)-4-thiophen-2-ylpyrrole-2,5-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C23H18N2O2S
assistant