You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [2-(4-nitrophenyl)-2-oxoethyl] (3aS,4S,9bS)-4-(4-nitrophenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-carboxylate into its molecular formula.
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C27H21N3O7
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