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What is the molecular formula of the compound with this IUPAC name [(3aR,4S,6aS)-2,3,3a,4,5,6a-hexahydrofuro[2,3-b]furan-4-yl] N-[(2S,3R)-3-hydroxy-4-[2-methylpropyl(phosphanyl)amino]-1-phenylbutan-2-yl]carbamate ?
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C21H33N2O5P
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