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What is the molecular formula of the compound with this IUPAC name methyl (3aS,4S,5R,7S,7aR)-4,7-dichloro-6-oxospiro[1,2,3,3a,7,7a-hexahydroindene-5,2'-oxolane]-4-carboxylate ?
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C14H18Cl2O4
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