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What is the molecular formula of the molecule identified by (3aS,4R,6aS)-2'-ethyl-2-(5-fluoropyrimidin-2-yl)-3'-(2-methoxyethyl)spiro[1,3,3a,5,6,6a-hexahydrocyclopenta[c]pyrrole-4,5'-imidazole]-4'-one ?
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C18H24FN5O2
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