You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-(2,3-dihydroindol-1-yl)-2-[4-(1,1-dioxothiolan-3-yl)piperazin-1-yl]ethanone into its molecular formula.
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C18H25N3O3S
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