You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 2-[1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl]-5-ethyl-4,5,6,6a-tetrahydro-3aH-cyclopenta[c]pyrrole-1,3-dione .
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C13H21NO5
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