You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by (5Z)-5-[(1-cyclopentyl-2,5-dimethylpyrrol-3-yl)methylidene]-3-phenyl-2-sulfanylidene-1,3-thiazolidin-4-one ?
user
C21H22N2OS2
assistant