You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-(3-methoxyphenyl)-N-[2-oxo-2-(2,3,4-trifluoroanilino)ethyl]-N-propylprop-2-enamide by IUPAC nomenclature, provide its molecular formula.
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C21H21F3N2O3
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