You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-[2-[[(2S)-2-(dimethylamino)-2-(3-fluorophenyl)ethyl]amino]-2-oxoethyl]-3,4-dimethoxybenzamide by IUPAC nomenclature, provide its molecular formula.
user
C21H26FN3O4
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