You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named 1-(3-amino-2-benzyl-1-methyl-3H-[1,3]dioxolo[4,5-i][1,2]benzodiazepin-4-yl)ethanone is given. What is its corresponding molecular formula?
user
C20H21N3O3
assistant