You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-chloro-4-fluoro-N-[3-oxo-3-[[4-(4-propoxyphenyl)-1,3-thiazol-2-yl]amino]propyl]benzamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H21ClFN3O3S
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