You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[4-(4,6-dioxo-3,5,9-triazatricyclo[9.4.0.03,7]pentadeca-1(15),11,13-triene-9-carbonyl)phenyl]acetamide into molecular formula.
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C21H20N4O4
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