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For the molecule named 1-[(2R,3S,5R)-4-[[(1R,3S,3aR)-3-methyl-3-phenyl-3a,4,5,6-tetrahydropyrrolo[1,2-c][1,3,2]oxazaphosphol-1-yl]oxy]-3-fluoro-5-(hydroxymethyl)oxolan-2-yl]pyrimidine-2,4-dione by IUPAC nomenclature, provide its molecular formula.
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C21H25FN3O6P
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