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-methoxy-N-[3-[(E)-3-oxo-3-(4-oxochromen-3-yl)prop-1-enyl]phenyl]acetamide is given. What is its corresponding molecular formula?
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C21H17NO5
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