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What is the molecular formula of the molecule identified by (1S,3S,3aR,6aS)-5-[(2S)-butan-2-yl]-5'-fluoro-1-[(1R)-1-hydroxyethyl]spiro[1,2,3a,6a-tetrahydropyrrolo[3,4-c]pyrrole-3,3'-1H-indole]-2',4,6-trione ?
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C19H22FN3O4
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