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system
Provide the molecular formula for the IUPAC named substance N-[3-[(8R)-10-amino-8-methyl-6,6-dioxo-2-oxa-6lambda6-thia-9-azaspiro[4.5]dec-9-en-8-yl]-4-fluorophenyl]-5-fluoropyridine-2-carboxamide .
user
C20H20F2N4O4S
assistant