You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(1R,2S,3R,4S,4aR,11bS)-2,3,4,7-tetrahydroxy-6-oxo-2,3,4,4a,5,11b-hexahydro-1H-[1,3]dioxolo[4,5-j]phenanthridin-1-yl]naphthalene-2-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H22N2O8
assistant