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 (4R)-N-(2-chlorophenyl)-4-(2,6-difluorophenyl)-6-methyl-2-oxo-3,4-dihydro-1H-pyrimidine-5-carboxamide into molecular formula.
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C18H14ClF2N3O2
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