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 (2S)-4-[[6-[[(3S)-3-hydroxybutyl]-methylamino]-2-(4-methoxyanilino)pyrimidin-4-yl]-methylamino]butan-2-ol into molecular formula.
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C21H33N5O3
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