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For the molecule named 2-(3,4-dichlorophenyl)-N,2-dimethyl-4-[(3R)-3-methyl-4-methylsulfonylpiperazin-1-yl]-N-[(4-methylphenyl)methyl]butanamide by IUPAC nomenclature, provide its molecular formula.
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C26H35Cl2N3O3S
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