You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(E)-3-(3-chloro-5-ethoxy-4-methoxyphenyl)-N-[3-methyl-4-(2-oxopyrrolidin-1-yl)phenyl]prop-2-enamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C23H25ClN2O4
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