You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-[2-[2-(4-fluorophenyl)-5-methyl-1,3-oxazol-4-yl]ethyl]-2-(4-methylphenoxy)acetamide by IUPAC nomenclature, provide its molecular formula.
user
C21H21FN2O3
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