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What is the molecular formula of the compound with this IUPAC name (3R,4R)-N-[(3-methoxyphenyl)methyl]-3-methyl-2,6-dioxo-7-azatricyclo[6.4.0.03,5]dodeca-1(12),8,10-triene-4-carboxamide ?
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C21H20N2O4
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