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What is the molecular formula of the molecule (3aR,8bS)-1-[(1R,2S,4S)-spiro[bicyclo[2.2.1]hept-5-ene-3,1'-cyclopropane]-2-carbonyl]-4,8b-dihydro-3aH-indeno[1,2-d][1,3]oxazol-2-one ?
user
C20H19NO3
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