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What is the molecular formula of the compound with this IUPAC name methyl (1S,3R,3aR,6aR)-5-ethyl-1-(furan-2-yl)-3-methyl-4,6-dioxo-1,2,3a,6a-tetrahydropyrrolo[3,4-c]pyrrole-3-carboxylate ?
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C15H18N2O5
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