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 5-bromo-N-ethyl-4-(3-methyl-3,4,6,7,8,8a-hexahydro-1H-pyrrolo[1,2-a]pyrazin-2-yl)pyrimidin-2-amine into molecular formula.
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C14H22BrN5
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