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What is the molecular formula of the molecule identified by methyl (1R,11S,14E,15S,17S)-14-ethylidene-18-oxa-2,12-diazahexacyclo[9.6.1.19,15.01,9.03,8.012,17]nonadeca-3,5,7-triene-19-carboxylate ?
user
C20H22N2O3
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