You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance (2R,3S,4R,5R)-2-[(R)-[3-(difluoromethyl)phenyl]-hydroxymethyl]-3-methyl-5-(4-methylpyrrolo[2,3-d]pyrimidin-7-yl)oxolane-3,4-diol .
user
C20H21F2N3O4
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