You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 2-amino-4-(4-chlorophenyl)-7-oxo-5,6-diphenyl-4,5-dihydropyrano[2,3-c]pyrrole-3-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C28H23ClN2O4
assistant