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Can you give the molecular formula of the molecule (2R,3R,4S)-3-acetamido-4-[[amino-(1-butanoyloxyethoxycarbonylamino)methylidene]amino]-2-[(2R,3R,4R)-3,4-dihydroxyoxan-2-yl]-3,4-dihydro-2H-pyran-6-carboxylic acid ?
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C21H32N4O11
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