You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[(3-methyl-8-oxo-9-phenyl-6,10-dihydrochromeno[3,4-f]isoindol-1-yl)methyl]oxolane-2,5-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C27H21NO5
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