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What is the molecular formula of the compound with this IUPAC name methyl (1S,3S,3aR,6aR)-1-(furan-2-yl)-5-methyl-4,6-dioxo-3-propyl-1,2,3a,6a-tetrahydropyrrolo[3,4-c]pyrrole-3-carboxylate ?
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C16H20N2O5
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