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What is the molecular formula of the compound with this IUPAC name (5R,6R,7aR)-N-(3-bromophenyl)-1'-ethyl-2'-oxospiro[3,6,7,7a-tetrahydro-1H-pyrrolo[1,2-c][1,3]thiazole-5,3'-indole]-6-carboxamide ?
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C22H22BrN3O2S
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