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 (2R)-3-[(2R)-butan-2-yl]-2-[(E)-2-phenylethenyl]-1,2-dihydroquinazolin-4-one is given. What is its corresponding molecular formula?
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C20H22N2O
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