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What is the molecular formula of the molecule 7a-prop-2-enyl-3-(trichloromethyl)-3,5,6,7-tetrahydropyrrolo[1,2-c][1,3]oxazol-1-one;3-bromoprop-1-ene;3-(trichloromethyl)-5,6,7,7a-tetrahydro-3H-pyrrolo[1,2-c][1,3]oxazol-1-one ?
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C20H25BrCl6N2O4
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