You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(5-methyl-1,2-oxazol-3-yl)-1,3-dioxo-2-[(1R)-1-phenylethyl]isoindole-5-carboxamide into its molecular formula.
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C21H17N3O4
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