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system
Provide the molecular formula for the IUPAC named substance (2S)-2-[[5-[2-[(6R)-2-amino-4-hydroxy-4,6,7,8-tetrahydro-1H-pyrimido[5,4-b][1,4]thiazin-6-yl]ethyl]thiophene-2-carbonyl]amino]pentanedioic acid .
user
C18H23N5O6S2
assistant