You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-(2,6-dimethylphenoxy)-N-[4-(2-methylpropyl)-3-oxo-1,4-benzoxazin-6-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
user
C22H26N2O4
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