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What is the molecular formula of the compound with this IUPAC name spiro[4,5-dihydrothieno[2,3-c]pyran-7,4'-piperidine]-1'-yl(5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyridin-3-yl)methanone ?
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C18H22N4O2S
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