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What is the molecular formula of the molecule (20R)-23-amino-4,17,20-trimethyl-21-oxa-4,5,7,12,13,24,26-heptazapentacyclo[20.3.1.02,6.08,13.014,19]hexacosa-1(25),2,5,7,9,11,14(19),15,17,22(26),23-undecaene-3-carbonitrile ?
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C22H19N9O
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