You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[(1R,2S)-3-[2-[(1R)-1-(6-aminopurin-9-yl)propoxy]ethoxy-hydroxyphosphinothioyl]oxy-1-(2-hydroxyethoxy)-2-methoxypropyl]pyrimidine-2,4-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H30N7O9PS
assistant