You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (E)-N-[[(2R,3S,4R,5R)-5-(6-aminopurin-9-yl)-3,4-dihydroxyoxolan-2-yl]methyl]-5-(2-nitrophenyl)-5-oxopent-1-ene-1-sulfonamide into its molecular formula.
user
C21H23N7O8S
assistant