You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named [(2R)-1-oxo-1-phenylpropan-2-yl] 1,3-dioxo-2-propan-2-ylisoindole-5-carboxylate is given. What is its corresponding molecular formula?
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C21H19NO5
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