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system
Provide the molecular formula for the IUPAC named substance 2-amino-9-[(6R,8R,9S,15R,17R,18S)-8-(6-aminopurin-9-yl)-9-fluoro-3,12,18-trihydroxy-12-oxo-3-sulfanylidene-2,4,7,11,13,16-hexaoxa-3lambda5,12lambda5-diphosphatricyclo[13.2.1.06,10]octadecan-17-yl]-1H-purin-6-one .
user
C20H23FN10O11P2S
assistant