You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2R)-2-(4-tert-butylphenoxy)-N-methyl-N-[2-[(5-methyl-1,2-oxazol-3-yl)amino]-2-oxoethyl]propanamide into its molecular formula.
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C20H27N3O4
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