You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Provide the molecular formula for the IUPAC named substance (8aS)-2-(3-bromo-4-nitrophenyl)-3,4,6,7,8,8a-hexahydro-1H-pyrrolo[1,2-a]pyrazine .
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C13H16BrN3O2
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