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-N-[(3-bromo-4-fluorophenyl)methyl]-4-N-(thiophen-2-ylmethyl)pyrimidine-4,6-dicarboxamide into molecular formula.
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C18H14BrFN4O2S
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