You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[2-(4-chlorobenzoyl)-1-ethyl-6-(trifluoromethyl)indol-3-yl]-2-ethylpropanedioic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C23H19ClF3NO5
assistant