You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3R,3aR,6aR)-3-(2-chloro-5-nitrophenyl)-5-(4-nitrophenyl)-2-phenyl-3a,6a-dihydro-3H-pyrrolo[3,4-d][1,2]oxazole-4,6-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C23H15ClN4O7
assistant