You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (4-cyclopentylpiperazin-1-yl)-(4-piperidin-1-yl-3-piperidin-1-ylsulfonylphenyl)methanone into molecular formula.
user
C26H40N4O3S
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