You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[[2-[[2-[(2-amino-3-methylpentanoyl)amino]-4-methylsulfanylbutanoyl]amino]-4-methylsulfanylbutanoyl]amino]-3-hydroxypropanoic acid by IUPAC nomenclature, provide its molecular formula.
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C19H36N4O6S2
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