You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[1-(5-chloro-2,4-dihydroxybenzoyl)pyrrolidin-2-yl]-N,N,3-trimethylbenzamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H23ClN2O4
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