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What is the molecular formula of the molecule N-[2-(4-chlorophenyl)ethyl]-2-(16-oxo-9-oxa-2,15,21-triazatricyclo[15.3.1.03,8]henicosa-1(20),3,5,7,17(21),18-hexaen-15-yl)acetamide ?
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C27H29ClN4O3
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