You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4aR,6R,7R,8R,8aS)-N-(2,4-dinitrophenyl)-2-phenyl-6,8-bis(phenylmethoxy)-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxin-7-amine The above is the IUPAC name of a molecule. Write its molecular formula.
user
C33H31N3O9
assistant