You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
sodium;(2S,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)-2-(6-oxo-1H-purin-9-yl)oxolane-2-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C11H11N4NaO7
assistant