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What is the molecular formula of the molecule identified by 4-methoxy-18-(methylamino)spiro[9-oxa-2,12,16,20,21-pentazatetracyclo[12.5.2.13,7.017,21]docosa-1(20),3,5,7(22),14,16,18-heptaene-11,1'-cyclopropane]-13-one ?
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C20H22N6O3
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