You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-methyl-2-[(3-methylphenyl)methyl]-6-phenyl-7,8-dihydropurino[7,8-a]imidazole-1,3-dione into its molecular formula.
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C22H21N5O2
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