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 1-[5-[6-(2-bromo-5-methoxyphenyl)-2-pyrazin-2-ylpyrimidin-4-yl]-1,3-thiazol-2-yl]-3-methylurea into molecular formula.
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C20H16BrN7O2S
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