You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
8-aminosulfanyloxy-12a-methyl-2-propyl-4,4a,4b,5,6,10b,11,12-octahydronaphtho[2,1-f]isoquinoline-1,3-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H28N2O3S
assistant