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system
Provide the molecular formula for the IUPAC named substance (6Z)-6-[[3-chloro-4-[(2-methylphenyl)methoxy]phenyl]methylidene]-5-imino-2-methylsulfonyl-[1,3,4]thiadiazolo[3,2-a]pyrimidin-7-one .
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C21H17ClN4O4S2
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