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system
Provide the molecular formula for the IUPAC named substance (3S)-3-amino-4-[(3S,4S)-3-(2,4-dioxopyrimidin-1-yl)-4-hydroxy-4-methyl-1-oxa-9-azaspiro[5.5]undecan-9-yl]-4-oxobutanoic acid .
user
C18H26N4O7
assistant