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system
Provide the molecular formula for the IUPAC named substance (1S,3aR,6aS)-5-(4-chlorophenyl)-1-(4-nitrophenyl)spiro[3a,6a-dihydro-1H-furo[3,4-c]pyrrole-3,2'-indene]-1',3',4,6-tetrone .
user
C26H15ClN2O7
assistant