You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 6-[(Z)-2-amino-4-oxopent-2-en-3-yl]-3-methyl-4-phenyl-1,4-dihydropyrido[3,4-d]pyrimidin-2-one into molecular formula.
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C19H20N4O2
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