You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Please write the molecular formula of the molecule (4-bromo-1-propylpyrrol-2-yl)-(3-methyl-3,4,6,7,8,8a-hexahydro-1H-pyrrolo[1,2-a]pyrazin-2-yl)methanone .
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C16H24BrN3O
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