You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (E)-2-acetamido-N-[[4-[2-(3-fluorophenyl)ethynyl]phenyl]methyl]-4-methoxybut-3-enamide by IUPAC nomenclature, provide its molecular formula.
user
C22H21FN2O3
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