You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 6-amino-4-(2,4-dichlorophenyl)-2-[(3,5-dimethoxyphenyl)methyl]-4,5-dihydropyrimidine-5-carbonitrile into its molecular formula.
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C20H18Cl2N4O2
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