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system
Name the molecular formula for the molecule established as 2-amino-9-[(1R,8R,10S,15S)-8-(8-aminoimidazo[1,2-b]pyridazin-3-yl)-3,12-dihydroxy-3,12-bis(sulfanylidene)-2,4,7,11,13,16-hexaoxa-3lambda5,12lambda5-diphosphatricyclo[13.2.1.06,10]octadecan-17-yl]-1H-purin-6-one using the IUPAC nomenclature.
user
C21H25N9O9P2S2
assistant