You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2R)-2-[(2-chlorophenyl)methyl-[2-[(4-chlorophenyl)sulfonyl-methylamino]acetyl]amino]-N-cyclopentylbutanamide by IUPAC nomenclature, provide its molecular formula.
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C25H31Cl2N3O4S
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