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What is the molecular formula of the molecule (1S,12S)-9-chloro-2-methyl-12-phenyl-15-oxa-2,5,13-triazatetracyclo[10.2.1.01,5.06,11]pentadeca-6(11),7,9,13-tetraene-3,4-dione ?
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C18H12ClN3O3
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