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 4-[(5Z)-5-[(2-chlorophenyl)methylidene]-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]-N-(4-ethoxyphenyl)butanamide ?
user
C22H21ClN2O3S2
assistant