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 tert-butyl (2S,3aR)-3a-amino-2-(oxocarbamoyl)-2,3,4,5,6,6a-hexahydrocyclopenta[b]pyrrole-1-carboxylate into molecular formula.
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C13H21N3O4
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