You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (5E)-3-(4-bromo-3-chlorophenyl)-5-[(1-propan-2-ylindol-3-yl)methylidene]-2-sulfanylidene-1,3-thiazolidin-4-one into its molecular formula.
user
C21H16BrClN2OS2
assistant