You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
5-[[1-(3-bromophenyl)-2,5-dimethylpyrrol-3-yl]methylidene]-3-ethyl-2-sulfanylidene-1,3-thiazolidin-4-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H17BrN2OS2
assistant