You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (3S)-3-hydroxy-6-methyl-4-(3-methylbutanoylamino)-N-[(2R)-1-(3-methylbutylamino)-1-oxopropan-2-yl]heptanamide is given. What is its corresponding molecular formula?
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C21H41N3O4
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