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system
Provide the molecular formula for the IUPAC named substance 1-(2-ethoxyethyl)-5-N-(2-methoxyethyl)-3-(methoxymethyl)-5-N-methyl-7-N-(4-methylpyridin-2-yl)pyrazolo[4,3-d]pyrimidine-5,7-diamine .
user
C21H31N7O3
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