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system
Name the molecular formula for the molecule established as methyl (2S,3aS,7aR)-1-[2-(2-methoxy-5-methylanilino)-2-oxoethyl]-2,3,3a,4,5,6,7,7a-octahydroindole-2-carboxylate using the IUPAC nomenclature.
user
C20H28N2O4
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