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What is the molecular formula of the compound with this IUPAC name [2-oxo-2-[[(2R)-3-oxo-1-phenylbutan-2-yl]amino]ethyl] (3S,7aS)-7a-methyl-5-oxo-2,3,6,7-tetrahydropyrrolo[2,1-b][1,3]thiazole-3-carboxylate ?
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C20H24N2O5S
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