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What is the molecular formula of the compound with this IUPAC name 2-[(1S)-2-[(3aS,6S,6aR)-6-(methylamino)-3-oxo-3a,5,6,6a-tetrahydrofuro[3,2-b]pyrrol-4-yl]-1-cyclopentyl-2-oxoethyl]benzamide ?
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C21H27N3O4
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