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What is the molecular formula of the compound with this IUPAC name (2S)-2-[(3R,4S,4aS,8aS)-4'-hydroxy-3,4a,8,8-tetramethyl-6',7-dioxospiro[1,2,3,5,6,8a-hexahydronaphthalene-4,2'-3,8-dihydrofuro[2,3-e]isoindole]-7'-yl]pentanedioic acid ?
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C28H35NO8
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