You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [(3S)-1,1-dioxothiolan-3-yl]-[(2S)-2-[5-ethyl-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-2-yl]pyrrolidin-1-yl]methanone into its molecular formula.
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C18H21F3N4O3S
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