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What is the molecular formula of the compound with this IUPAC name (2R,5S,11S,14S,17S,18E)-2,2',2',11-tetramethyl-14-propan-2-ylspiro[15-oxa-3,9,12,26,29-pentazatetracyclo[18.5.3.15,9.023,27]nonacosa-1(26),18,20(28),21,23(27),24-hexaene-17,4'-oxane]-4,10,13,16-tetrone;(2R,5S,11S,14S,18E)-2,2',2',11-tetramethyl-14-propan-2-ylspiro[15-oxa-3,9,12,26,29-pentazatetracyclo[18.5.3.15,9.023,27]nonacosa-1(26),18,20(28),21,23(27),24-hexaene-17,4'-oxane]-4,10,13,16-tetrone ?
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C68H90N10O12
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