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system
Name the molecular formula for the molecule established as (4R)-9-[(3R)-3-hydroxy-3-pyrimidin-2-ylbut-1-ynyl]-4-methyl-4,5-dihydropyrazolo[5,1-d][1,5]benzoxazepine-2-carboxamide using the IUPAC nomenclature.
user
C21H19N5O3
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