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system
Name the molecular formula for the molecule established as 1-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)-2-[4-[5-(trifluoromethyl)pyridin-2-yl]piperazin-1-yl]butan-1-one using the IUPAC nomenclature.
user
C21H25F3N4OS
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