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What is the molecular formula of the molecule (2R)-1-(3,3a,4,5,6,7,8,8a-octahydro-1H-pyrrolo[3,4-d]azepin-2-yl)-2-[(1R)-3,3-difluorocyclopentyl]-2-hydroxy-2-phenylethanone ?
user
C21H28F2N2O2
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