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system
Provide the molecular formula for the IUPAC named substance 3-[5'-fluoro-5-(3-methoxypropyl)-2',4,6-trioxospiro[1,2,3a,6a-tetrahydropyrrolo[3,4-c]pyrrole-3,3'-1H-indole]-1-yl]propanoic acid .
user
C20H22FN3O6
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