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system
Provide the molecular formula for the IUPAC named substance (4-nitrophenyl) 3-[(3aR,4R,6R,6aR)-4-(6-aminopurin-9-yl)-2,2-dimethyl-3a,4,6,6a-tetrahydrofuro[3,4-d][1,3]dioxol-6-yl]propanoate .
user
C21H22N6O7
assistant