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What is the molecular formula of the molecule identified by 1-[(5aS,8aS)-4-(furan-3-ylmethyl)-3,5,5a,6,8,8a-hexahydro-2H-pyrrolo[3,4-f][1,4]oxazepin-7-yl]-2-(1-hydroxycyclobutyl)ethanone ?
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C18H26N2O4
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