You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[2-(3-ethylanilino)-6-methylpyrimidin-4-yl]oxy-N-(5-methyl-1,2-oxazol-3-yl)acetamide into molecular formula.
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C19H21N5O3
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