You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2E)-2-[(1-ethylindol-3-yl)methylidene]-7-methyl-3-oxo-1-benzofuran-6-yl] 4-fluorobenzenesulfonate is the IUPAC name of a molecule. Please give its molecular formula.
user
C26H20FNO5S
assistant