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system
Name the molecular formula for the molecule established as methyl 2-[4-[2-cyano-2-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-3-yl)ethenyl]-2,6-dimethylphenoxy]acetate using the IUPAC nomenclature.
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C21H24N4O3
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