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system
Provide the molecular formula for the IUPAC named substance ethyl 7-chloro-3-[3-methoxy-4-(2-methyl-1,3-oxazol-5-yl)phenyl]-5,6-dihydro-4H-triazolo[1,5-a]pyridine-7-carboxylate .
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C20H21ClN4O4
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