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system
Provide the molecular formula for the IUPAC named substance [[[5-(2-amino-6-oxo-1H-purin-9-yl)-3,4-dihydroxyoxolan-2-yl]methoxy-hydroxyphosphoryl]oxy-hydroxyphosphoryl]oxy-N-(4-azidophenyl)phosphonamidic acid .
user
C16H20N9O13P3
assistant