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system
Name the molecular formula for the molecule established as [[(2R,5R)-5-[3-[(5-chloro-4-phenylpyridin-2-yl)methyl]-2,4-dioxopyrimidin-1-yl]-3,4-dihydroxyoxolan-2-yl]methoxy-hydroxyphosphoryl] phosphono hydrogen phosphate using the IUPAC nomenclature.
user
C21H23ClN3O15P3
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