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 2-[(4R)-1-(4-chlorophenyl)-3-(2-methylpropyl)-2,5-dioxoimidazolidin-4-yl]-N-(4-fluorophenyl)acetamide is given. What is its corresponding molecular formula?
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C21H21ClFN3O3
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